Update documentation

added dependencies to nuspec and fixed build

.bettercodehub.yml

@@ -0,0 +1,8 @@
+exclude:
+- /Frameworks/.*
+- /MQTTnet.TestApp.NetCore/Program.cs
+- /Tests/MQTTnet.TestApp.NetFramework/.*
+- /Tests/MQTTnet.TestApp.UniversalWindows/.*
+component_depth: 1
+languages:
+- csharp

.gitignore

@@ -197,7 +197,7 @@ ClientBin/
 *.dbmdl
 *.dbproj.schemaview
 *.jfm
-*.pfx
+# *.pfx
 *.publishsettings
 orleans.codegen.cs
 
@@ -289,3 +289,5 @@ __pycache__/
 
 
 Build/nuget.exe
+*.js
+*.map

Build/MQTTnet.AspNetCore.nuspec

@@ -0,0 +1,28 @@
+<?xml version="1.0"?>
+<package >
+  <metadata>
+    <id>MQTTnet.AspNetCore</id>
+    <version>2.5.0</version>
+    <authors>Christian Kratky</authors>
+    <owners>Christian Kratky</owners>
+    <licenseUrl>https://github.com/chkr1011/MQTTnet/blob/master/LICENSE</licenseUrl>
+    <projectUrl>https://github.com/chkr1011/MQTTnet</projectUrl>
+    <iconUrl>https://raw.githubusercontent.com/chkr1011/MQTTnet/master/Images/Logo_128x128.png</iconUrl>
+    <requireLicenseAcceptance>false</requireLicenseAcceptance>
+    <description>This is a support library to integrate MQTTnet into AspNetCore.</description>
+    <releaseNotes>initial version
+    </releaseNotes>
+    <copyright>Copyright Christian Kratky 2016-2017</copyright>
+    <tags>MQTT Message Queue Telemetry Transport MQTTClient MQTTServer Server MQTTBroker Broker NETStandard IoT InternetOfThings Messaging Hardware Arduino Sensor Actuator M2M ESP Smart Home Cities Automation Xamarin</tags> 
+    <dependencies>
+      <group targetFramework="netstandard2.0">
+        <dependency id="MQTTnet" version="2.5" />
+      </group>
+    </dependencies>
+  </metadata>
+
+  <files>
+    <!-- .NET Standard 2.0 -->
+    <file src="..\Frameworks\MQTTnet.AspNetCore\bin\Release\netstandard2.0\MQTTnet.AspNetCore.*" target="lib\netstandard2.0\"/>
+  </files>
+</package>

Build/MQTTnet.nuspec

@@ -2,33 +2,57 @@
 <package >
   <metadata>
     <id>MQTTnet</id>
-    <version>2.3.0</version>
+    <version>2.5.0</version>
     <authors>Christian Kratky</authors>
     <owners>Christian Kratky</owners>
     <licenseUrl>https://github.com/chkr1011/MQTTnet/blob/master/LICENSE</licenseUrl>
     <projectUrl>https://github.com/chkr1011/MQTTnet</projectUrl>
     <iconUrl>https://raw.githubusercontent.com/chkr1011/MQTTnet/master/Images/Logo_128x128.png</iconUrl>
     <requireLicenseAcceptance>false</requireLicenseAcceptance>
-    <description>MQTTnet is a .NET library for MQTT based communication. It provides a MQTT client and a MQTT server (broker).</description>
-    <releaseNotes>* [Client] Added support for web socket communication channel (thanks to nowakpiotr)
-* [Core] Huge performance optimizations (thanks to JanEggers)
-* [Client] Fixed an issue when calling _DisconnectAsync_ and the connection is already closed.
-* [Core] Added several new interfaces
-* [Core] Added a factory for creation of application messages
-* [Core] Fixed issues in connection handling
-* [Client] Fixed issues with subscribing/unsubscribing (breaking change!)
+    <description>MQTTnet is a high performance .NET library for MQTT based communication. It provides a MQTT client and a MQTT server (broker).</description>
+    <releaseNotes>* [Core] Merged the platform specific projects (Thanks to @JanEggers)
+* [Core] Migrated the trace to a non-static approach (Breaking Change!)
+* [Core] Added a builder for application messages using a fluent API
+* [Core] Introduced CI and DI (Thanks to @JanEggers)
+* [Core] Added interfaces for publishing and receiving which applies to every client and server (Thanks to @ChristianRiedl)
+* [Core] Fixed an issue when reading from closed streams
+* [Client] Added a first version of a managed client which will manage the connection, subscription etc. automatically (Thanks to @JTrotta)
+* [Client] The session state response from the server is now returned in the _ConnectAsync_ method and also part of the _Connected_ event args
+* [Client] Added a _TopicFilterBuilder_ using a fluent API (Namespace Changes!)
+* [Client] Added several new options for the WebSocket channel (Thanks to @ChristianRiedl)
+* [Client] Refactored the options and added a builder using a fluent API (Breaking Change!)
+* [Client] Added more options for WebSocket connections like RequestHeaders, SubProtocol etc.
+* [Server] Added support for WebSockets via ASP.NET Core 2.0 (additional nuget) (Thanks to @ChristianRiedl, @JanEggers)
+* [Server] Added support for a custom application message interceptor
+* [Server] Fixed an issue with dropped connections on UWP (Thanks to @haeberle)
+* [Server] Added support for a custom subscription interceptor which allows denying of subscriptions and closing the connection
     </releaseNotes>
     <copyright>Copyright Christian Kratky 2016-2017</copyright>
-    <tags>MQTT Message Queue Telemetry Transport MQTTClient MQTTServer Server MQTTBroker Broker NETStandard IoT InternetOfThings Messaging Hardware Arduino Sensor Actuator M2M</tags> 
+    <tags>MQTT Message Queue Telemetry Transport MQTTClient MQTTServer Server MQTTBroker Broker NETStandard IoT InternetOfThings Messaging Hardware Arduino Sensor Actuator M2M ESP Smart Home Cities Automation Xamarin</tags> 
     <dependencies>
 
       <group targetFramework="netstandard1.3">
         <dependency id="NETStandard.Library" version="1.6.1" />
-        <dependency id="System.Net.Security" version="4.3.1" />
+        <dependency id="Microsoft.Extensions.DependencyInjection" version="1.1.1" />
+        <dependency id="Microsoft.Extensions.Logging" version="1.1.2" />
+        <dependency id="Microsoft.Extensions.Options" version="1.1.2" />
+        <dependency id="System.Net.Security" version="4.3.2" />
+        <dependency id="System.Net.WebSockets" version="4.3.0" />
+        <dependency id="System.Net.WebSockets.Client" version="4.3.1" />
+        <dependency id="System.Threading.Thread" version="4.3.0" />
       </group>
       
       <group targetFramework="uap10.0">
         <dependency id="Microsoft.NETCore.UniversalWindowsPlatform" version="5.4.0" />
+        <dependency id="Microsoft.Extensions.DependencyInjection" version="1.1.1" />
+        <dependency id="Microsoft.Extensions.Logging" version="1.1.2" />
+        <dependency id="Microsoft.Extensions.Options" version="1.1.2" />
+      </group>
+        
+      <group targetFramework="net451">
+        <dependency id="Microsoft.Extensions.DependencyInjection" version="1.1.1" />
+        <dependency id="Microsoft.Extensions.Logging" version="1.1.2" />
+        <dependency id="Microsoft.Extensions.Options" version="1.1.2" />
       </group>
 
     </dependencies>
@@ -40,12 +64,12 @@
     <file src="..\Frameworks\MQTTnet.Netstandard\bin\Release\netstandard1.3\MQTTnet.*" target="lib\netstandard1.3\"/>
 
     <!-- Universal Windows -->
-    <file src="..\Frameworks\MQTTnet.UniversalWindows\bin\Release\MQTTnet.Core.*" target="lib\uap10.0\"/>
-    <file src="..\Frameworks\MQTTnet.UniversalWindows\bin\Release\MQTTnet.*" target="lib\uap10.0\"/>
+    <file src="..\Frameworks\MQTTnet.Netstandard\bin\Release\uap10.0\MQTTnet.Core.*" target="lib\uap10.0\"/>
+    <file src="..\Frameworks\MQTTnet.Netstandard\bin\Release\uap10.0\MQTTnet.*" target="lib\uap10.0\"/>
 
     <!-- .NET Framework -->
-    <file src="..\Frameworks\MQTTnet.NetFramework\bin\Release\MQTTnet.Core.*" target="lib\net45\"/>
-    <file src="..\Frameworks\MQTTnet.NetFramework\bin\Release\MQTTnet.*" target="lib\net45\"/>
+    <file src="..\Frameworks\MQTTnet.Netstandard\bin\Release\net452\MQTTnet.Core.*" target="lib\net452\"/>
+    <file src="..\Frameworks\MQTTnet.Netstandard\bin\Release\net452\MQTTnet.*" target="lib\net452\"/>
     
   </files>
 </package>

Build/build.ps1

@@ -2,11 +2,21 @@ param([string]$version)
 
 if ([string]::IsNullOrEmpty($version)) {$version = "0.0.1"}
 
-$msbuild = "MSBuild.exe"
-&$msbuild ..\Frameworks\MQTTnet.NetFramework\MQTTnet.NetFramework.csproj /t:Build /p:Configuration="Release"
-&$msbuild ..\Frameworks\MQTTnet.Netstandard\MQTTnet.Netstandard.csproj /t:Build /p:Configuration="Release"
-&$msbuild ..\Frameworks\MQTTnet.UniversalWindows\MQTTnet.UniversalWindows.csproj /t:Build /p:Configuration="Release"
+$vswhere = ${Env:\ProgramFiles(x86)} + '\Microsoft Visual Studio\Installer\vswhere'
+
+$path = &$vswhere -latest -products * -requires Microsoft.Component.MSBuild -property installationPath
+if ($path) {
+    $msbuild = join-path $path 'MSBuild\15.0\Bin\MSBuild.exe'
+
+    &$msbuild ..\Frameworks\MQTTnet.Netstandard\MQTTnet.Netstandard.csproj /t:Build /p:Configuration="Release" /p:TargetFramework="net452" /p:FileVersion=$version /p:AssemblyVersion=$version /verbosity:m
+    &$msbuild ..\Frameworks\MQTTnet.Netstandard\MQTTnet.Netstandard.csproj /t:Build /p:Configuration="Release" /p:TargetFramework="netstandard1.3" /p:FileVersion=$version /p:AssemblyVersion=$version /verbosity:m
+    &$msbuild ..\Frameworks\MQTTnet.Netstandard\MQTTnet.Netstandard.csproj /t:Build /p:Configuration="Release" /p:TargetFramework="uap10.0" /p:FileVersion=$version /p:AssemblyVersion=$version /verbosity:m
+    
+	&$msbuild ..\Frameworks\MQTTnet.AspNetCore\MQTTnet.AspNetCore.csproj /t:Build /p:Configuration="Release" /p:TargetFramework="netstandard2.0" /p:FileVersion=$version /p:AssemblyVersion=$version /verbosity:m
+
+    Remove-Item .\NuGet -Force -Recurse
+    New-Item -ItemType Directory -Force -Path .\NuGet
+    .\NuGet.exe pack MQTTnet.nuspec -Verbosity detailed -Symbols -OutputDir "NuGet" -Version $version
+    .\NuGet.exe pack MQTTnet.AspNetCore.nuspec -Verbosity detailed -Symbols -OutputDir "NuGet" -Version $version
+}
 
-Remove-Item .\NuGet -Force -Recurse
-New-Item -ItemType Directory -Force -Path .\NuGet
-.\NuGet.exe pack MQTTnet.nuspec -Verbosity detailed -Symbols -OutputDir "NuGet" -Version $version

Frameworks/MQTTnet.AspnetCore/ApplicationBuilderExtensions.cs

@@ -0,0 +1,41 @@
+using System;
+using Microsoft.AspNetCore.Builder;
+using Microsoft.Extensions.DependencyInjection;
+using MQTTnet.Core.Server;
+
+namespace MQTTnet.AspNetCore
+{
+    public static class ApplicationBuilderExtensions
+    {
+        public static IApplicationBuilder UseMqttEndpoint(this IApplicationBuilder app, string path = "/mqtt")
+        {
+            app.UseWebSockets();
+            app.Use(async (context, next) =>
+            {
+                if (context.Request.Path == path && context.WebSockets.IsWebSocketRequest)
+                {
+                    var adapter = app.ApplicationServices.GetRequiredService<MqttWebSocketServerAdapter>();
+                    using (var webSocket = await context.WebSockets.AcceptWebSocketAsync("mqtt"))
+                    {
+                        await adapter.AcceptWebSocketAsync(webSocket);
+                    }
+                }
+                else
+                {
+                    await next();
+                }
+            });
+
+            return app;
+        }
+
+        public static IApplicationBuilder UseMqttServer(this IApplicationBuilder app, Action<IMqttServer> configure)
+        {
+            var server = app.ApplicationServices.GetRequiredService<IMqttServer>();
+
+            configure(server);
+
+            return app;
+        }
+    }
+}

Frameworks/MQTTnet.AspnetCore/MQTTnet.AspnetCore.csproj

@@ -0,0 +1,17 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>netstandard2.0</TargetFramework>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.AspNetCore.Http.Abstractions" Version="2.0.0" />
+    <PackageReference Include="Microsoft.AspNetCore.WebSockets" Version="2.0.0" />
+    <PackageReference Include="Microsoft.Extensions.Hosting.Abstractions" Version="2.0.0" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\MQTTnet.Netstandard\MQTTnet.NetStandard.csproj" />
+  </ItemGroup>
+
+</Project>

Frameworks/MQTTnet.AspnetCore/MqttHostedServer.cs

@@ -0,0 +1,35 @@
+using System.Collections.Generic;
+using System.Threading;
+using System.Threading.Tasks;
+using Microsoft.Extensions.Hosting;
+using Microsoft.Extensions.Logging;
+using Microsoft.Extensions.Options;
+using MQTTnet.Core.Adapter;
+using MQTTnet.Core.Server;
+
+namespace MQTTnet.AspNetCore
+{
+    public class MqttHostedServer : MqttServer, IHostedService
+    {
+        public MqttHostedServer(
+            IOptions<MqttServerOptions> options,
+            IEnumerable<IMqttServerAdapter> adapters,
+            ILogger<MqttServer> logger, 
+            MqttClientSessionsManager clientSessionsManager,
+            IMqttClientRetainedMessageManager clientRetainedMessageManager
+            ) 
+            : base(options, adapters, logger, clientSessionsManager, clientRetainedMessageManager)
+        {
+        }
+
+        public Task StartAsync(CancellationToken cancellationToken)
+        {
+            return StartAsync();
+        }
+
+        public Task StopAsync(CancellationToken cancellationToken)
+        {
+            return StopAsync();
+        }
+    }
+}

Frameworks/MQTTnet.AspnetCore/MqttWebSocketServerAdapter.cs

@@ -0,0 +1,93 @@
+using System;
+using System.IO;
+using System.Net.WebSockets;
+using System.Threading;
+using System.Threading.Tasks;
+using MQTTnet.Core.Adapter;
+using MQTTnet.Core.Channel;
+using MQTTnet.Core.Server;
+using MQTTnet.Implementations;
+
+namespace MQTTnet.AspNetCore
+{
+    public class MqttWebSocketServerAdapter : IMqttServerAdapter, IDisposable
+    {
+        private readonly IMqttCommunicationAdapterFactory _mqttCommunicationAdapterFactory;
+
+        public MqttWebSocketServerAdapter(IMqttCommunicationAdapterFactory mqttCommunicationAdapterFactory)
+        {
+            _mqttCommunicationAdapterFactory = mqttCommunicationAdapterFactory ?? throw new ArgumentNullException(nameof(mqttCommunicationAdapterFactory));
+        }
+
+        public event EventHandler<MqttServerAdapterClientAcceptedEventArgs> ClientAccepted;
+
+        public Task StartAsync(MqttServerOptions options)
+        {
+            return Task.CompletedTask;
+        }
+
+        public Task StopAsync()
+        {
+            return Task.CompletedTask;
+        }
+
+        public Task AcceptWebSocketAsync(WebSocket webSocket)
+        {
+            if (webSocket == null) throw new ArgumentNullException(nameof(webSocket));
+
+            var channel = new MqttWebSocketServerChannel(webSocket);
+            var clientAdapter = _mqttCommunicationAdapterFactory.CreateServerCommunicationAdapter(channel);
+
+            var eventArgs = new MqttServerAdapterClientAcceptedEventArgs(clientAdapter);
+            ClientAccepted?.Invoke(this, eventArgs);
+            return eventArgs.SessionTask;
+        }
+        
+        public void Dispose()
+        {
+            StopAsync();
+        }
+
+        private class MqttWebSocketServerChannel : IMqttCommunicationChannel, IDisposable
+        {
+            private readonly WebSocket _webSocket;
+
+            public MqttWebSocketServerChannel(WebSocket webSocket)
+            {
+                _webSocket = webSocket ?? throw new ArgumentNullException(nameof(webSocket));
+
+                RawReceiveStream = new WebSocketStream(_webSocket);
+            }
+
+            public Stream SendStream => RawReceiveStream;
+            public Stream ReceiveStream => RawReceiveStream;
+            public Stream RawReceiveStream { get; }
+
+            public Task ConnectAsync()
+            {
+                return Task.CompletedTask;
+            }
+
+            public Task DisconnectAsync()
+            {
+                RawReceiveStream?.Dispose();
+
+                if (_webSocket == null)
+                {
+                    return Task.CompletedTask;
+                }
+
+                return _webSocket.CloseAsync(WebSocketCloseStatus.NormalClosure, string.Empty, CancellationToken.None);
+            }
+
+            public void Dispose()
+            {
+                RawReceiveStream?.Dispose();
+                SendStream?.Dispose();
+                ReceiveStream?.Dispose();
+
+                _webSocket?.Dispose();
+            }
+        }
+    }
+}

Frameworks/MQTTnet.AspnetCore/ServiceCollectionExtensions.cs

@@ -0,0 +1,24 @@
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Hosting;
+using MQTTnet.Core.Adapter;
+using MQTTnet.Core.Server;
+
+namespace MQTTnet.AspNetCore
+{
+    public static class ServiceCollectionExtensions
+    {
+        public static IServiceCollection AddHostedMqttServer(this IServiceCollection services)
+        {
+            services.AddMqttServerServices();
+
+            services.AddSingleton<IHostedService>(s => s.GetService<MqttHostedServer>());
+            services.AddSingleton<IMqttServer>(s => s.GetService<MqttHostedServer>());
+            services.AddSingleton<MqttHostedServer>();
+            
+            services.AddSingleton<MqttWebSocketServerAdapter>();
+            services.AddSingleton<IMqttServerAdapter>(s => s.GetService<MqttWebSocketServerAdapter>());
+
+            return services;
+        }
+    }
+}

Frameworks/MQTTnet.NetFramework/Implementations/MqttServerAdapter.cs

@@ -1,129 +0,0 @@
-using System;
-using System.Net;
-using System.Net.Security;
-using System.Net.Sockets;
-using System.Security.Authentication;
-using System.Security.Cryptography.X509Certificates;
-using System.Threading;
-using System.Threading.Tasks;
-using MQTTnet.Core.Adapter;
-using MQTTnet.Core.Diagnostics;
-using MQTTnet.Core.Serializer;
-using MQTTnet.Core.Server;
-
-namespace MQTTnet.Implementations
-{
-    public class MqttServerAdapter : IMqttServerAdapter, IDisposable
-    {
-        private CancellationTokenSource _cancellationTokenSource;
-        private Socket _defaultEndpointSocket;
-        private Socket _tlsEndpointSocket;
-        private X509Certificate2 _tlsCertificate;
-
-        private bool _isRunning;
-
-        public event EventHandler<MqttClientConnectedEventArgs> ClientConnected;
-
-        public void Start(MqttServerOptions options)
-        {
-            if (options == null) throw new ArgumentNullException(nameof(options));
-
-            if (_isRunning) throw new InvalidOperationException("Server is already started.");
-            _isRunning = true;
-
-            _cancellationTokenSource = new CancellationTokenSource();
-
-            if (options.DefaultEndpointOptions.IsEnabled)
-            {
-                _defaultEndpointSocket = new Socket(SocketType.Stream, ProtocolType.Tcp);
-                _defaultEndpointSocket.Bind(new IPEndPoint(IPAddress.Any, options.GetDefaultEndpointPort()));
-                _defaultEndpointSocket.Listen(options.ConnectionBacklog);
-
-                Task.Run(() => AcceptDefaultEndpointConnectionsAsync(_cancellationTokenSource.Token), _cancellationTokenSource.Token);
-            }
-
-            if (options.TlsEndpointOptions.IsEnabled)
-            {
-                if (options.TlsEndpointOptions.Certificate == null)
-                {
-                    throw new ArgumentException("TLS certificate is not set.");
-                }
-
-                _tlsCertificate = new X509Certificate2(options.TlsEndpointOptions.Certificate);
-
-                _tlsEndpointSocket = new Socket(SocketType.Stream, ProtocolType.Tcp);
-                _tlsEndpointSocket.Bind(new IPEndPoint(IPAddress.Any, options.GetTlsEndpointPort()));
-                _tlsEndpointSocket.Listen(options.ConnectionBacklog);
-
-                Task.Run(() => AcceptTlsEndpointConnectionsAsync(_cancellationTokenSource.Token), _cancellationTokenSource.Token);
-            }
-        }
-
-        public void Stop()
-        {
-            _isRunning = false;
-
-            _cancellationTokenSource?.Cancel(false);
-            _cancellationTokenSource?.Dispose();
-            _cancellationTokenSource = null;
-
-            _defaultEndpointSocket?.Dispose();
-            _defaultEndpointSocket = null;
-
-            _tlsEndpointSocket?.Dispose();
-            _tlsEndpointSocket = null;
-        }
-
-        public void Dispose()
-        {
-            Stop();
-        }
-
-        private async Task AcceptDefaultEndpointConnectionsAsync(CancellationToken cancellationToken)
-        {
-            while (!cancellationToken.IsCancellationRequested)
-            {
-                try
-                {
-                    var clientSocket = await Task.Factory.FromAsync(_defaultEndpointSocket.BeginAccept, _defaultEndpointSocket.EndAccept, null).ConfigureAwait(false);
-
-                    var tcpChannel = new MqttTcpChannel(clientSocket, null);
-                    var clientAdapter = new MqttChannelCommunicationAdapter(tcpChannel, new MqttPacketSerializer());
-                    ClientConnected?.Invoke(this, new MqttClientConnectedEventArgs(clientSocket.RemoteEndPoint.ToString(), clientAdapter));
-                }
-                catch (Exception exception) when (!(exception is ObjectDisposedException))
-                {
-                    MqttTrace.Error(nameof(MqttServerAdapter), exception, "Error while accepting connection at default endpoint.");
-
-                    //excessive CPU consumed if in endless loop of socket errors
-                    await Task.Delay(TimeSpan.FromSeconds(1), cancellationToken).ConfigureAwait(false);
-                }
-            }
-        }
-
-        private async Task AcceptTlsEndpointConnectionsAsync(CancellationToken cancellationToken)
-        {
-            while (!cancellationToken.IsCancellationRequested)
-            {
-                try
-                {
-                    var clientSocket = await Task.Factory.FromAsync(_tlsEndpointSocket.BeginAccept, _tlsEndpointSocket.EndAccept, null).ConfigureAwait(false);
-
-                    var sslStream = new SslStream(new NetworkStream(clientSocket));
-                    await sslStream.AuthenticateAsServerAsync(_tlsCertificate, false, SslProtocols.Tls12, false).ConfigureAwait(false);
-
-                    var tcpChannel = new MqttTcpChannel(clientSocket, sslStream);
-                    var clientAdapter = new MqttChannelCommunicationAdapter(tcpChannel, new MqttPacketSerializer());
-                    ClientConnected?.Invoke(this, new MqttClientConnectedEventArgs(clientSocket.RemoteEndPoint.ToString(), clientAdapter));
-                }
-                catch (Exception exception)
-                {
-                    MqttTrace.Error(nameof(MqttServerAdapter), exception, "Error while accepting connection at TLS endpoint.");
-
-                    //excessive CPU consumed if in endless loop of socket errors
-                    await Task.Delay(TimeSpan.FromSeconds(1), cancellationToken).ConfigureAwait(false);
-                }
-            }
-        }
-    }
-}

Frameworks/MQTTnet.NetFramework/Implementations/MqttTcpChannel.cs

@@ -1,116 +0,0 @@
-using System;
-using System.Net.Security;
-using System.Net.Sockets;
-using System.Security.Authentication;
-using System.Security.Cryptography.X509Certificates;
-using System.Threading.Tasks;
-using MQTTnet.Core.Channel;
-using MQTTnet.Core.Client;
-using System.IO;
-
-namespace MQTTnet.Implementations
-{
-    public sealed class MqttTcpChannel : IMqttCommunicationChannel, IDisposable
-    {
-        // ReSharper disable once MemberCanBePrivate.Global
-        // ReSharper disable once AutoPropertyCanBeMadeGetOnly.Global
-        public static int BufferSize { get; set; } = 4096 * 20; // Can be changed for fine tuning by library user.
-
-        private Socket _socket;
-        private SslStream _sslStream;
-
-        /// <summary>
-        /// called on client sockets are created in connect
-        /// </summary>
-        public MqttTcpChannel()
-        {
-
-        }
-
-        /// <summary>
-        /// called on server, sockets are passed in
-        /// connect will not be called
-        /// </summary>
-        public MqttTcpChannel(Socket socket, SslStream sslStream)
-        {
-            _socket = socket ?? throw new ArgumentNullException(nameof(socket));
-            _sslStream = sslStream;
-            CreateStreams(socket, sslStream);
-        }
-
-        public Stream SendStream { get; private set; }
-        public Stream ReceiveStream { get; private set; }
-        public Stream RawReceiveStream { get; private set; }
-
-        public async Task ConnectAsync(MqttClientOptions options)
-        {
-            if (options == null) throw new ArgumentNullException(nameof(options));
-
-            if (_socket == null)
-            {
-                _socket = new Socket(SocketType.Stream, ProtocolType.Tcp);
-            }
-
-            await Task.Factory.FromAsync(_socket.BeginConnect, _socket.EndConnect, options.Server, options.GetPort(), null).ConfigureAwait(false);
-
-            if (options.TlsOptions.UseTls)
-            {
-                _sslStream = new SslStream(new NetworkStream(_socket, true));
-
-                await _sslStream.AuthenticateAsClientAsync(options.Server, LoadCertificates(options), SslProtocols.Tls12, options.TlsOptions.CheckCertificateRevocation).ConfigureAwait(false);
-            }
-
-            CreateStreams(_socket, _sslStream);
-        }
-
-        public Task DisconnectAsync()
-        {
-            Dispose();
-            return Task.FromResult(0);
-        }
-
-        public void Dispose()
-        {
-            RawReceiveStream?.Dispose();
-            RawReceiveStream = null;
-
-            ReceiveStream?.Dispose();
-            ReceiveStream = null;
-
-            SendStream?.Dispose();
-            SendStream = null;
-
-            _socket?.Dispose();
-            _socket = null;
-
-            _sslStream?.Dispose();
-            _sslStream = null;
-        }
-
-        private void CreateStreams(Socket socket, Stream sslStream)
-        {
-            RawReceiveStream = sslStream ?? new NetworkStream(socket);
-
-            //cannot use this as default buffering prevents from receiving the first connect message
-            //need two streams otherwise read and write have to be synchronized
-            SendStream = new BufferedStream(RawReceiveStream, BufferSize);
-            ReceiveStream = new BufferedStream(RawReceiveStream, BufferSize);
-        }
-
-        private static X509CertificateCollection LoadCertificates(MqttClientOptions options)
-        {
-            var certificates = new X509CertificateCollection();
-            if (options.TlsOptions.Certificates == null)
-            {
-                return certificates;
-            }
-
-            foreach (var certificate in options.TlsOptions.Certificates)
-            {
-                certificates.Add(new X509Certificate(certificate));
-            }
-
-            return certificates;
-        }
-    }
-}

Frameworks/MQTTnet.NetFramework/Implementations/MqttWebSocketChannel.cs

@@ -1,55 +0,0 @@
-using MQTTnet.Core.Channel;
-using MQTTnet.Core.Client;
-using System;
-using System.IO;
-using System.Net.WebSockets;
-using System.Threading;
-using System.Threading.Tasks;
-
-namespace MQTTnet.Implementations
-{
-    public sealed class MqttWebSocketChannel : IMqttCommunicationChannel, IDisposable
-    {
-        private ClientWebSocket _webSocket;
-
-        public Stream RawReceiveStream { get; private set; }
-        public Stream SendStream => RawReceiveStream;
-        public Stream ReceiveStream => RawReceiveStream;
-
-        public async Task ConnectAsync(MqttClientOptions options)
-        {
-            var uri = options.Server;
-            if (!uri.StartsWith("ws://", StringComparison.OrdinalIgnoreCase))
-            {
-                uri = "ws://" + uri;
-            }
-
-            if (options.Port.HasValue)
-            {
-                uri += ":" + options.Port;
-            }
-            
-            _webSocket = new ClientWebSocket();
-            _webSocket.Options.KeepAliveInterval = options.KeepAlivePeriod;
-            await _webSocket.ConnectAsync(new Uri(uri), CancellationToken.None).ConfigureAwait(false);
-            RawReceiveStream = new WebSocketStream(_webSocket);
-        }
-
-        public async Task DisconnectAsync()
-        {
-            RawReceiveStream = null;
-
-            if (_webSocket == null)
-            {
-                return;
-            }
-
-            await _webSocket.CloseAsync(WebSocketCloseStatus.NormalClosure, string.Empty, CancellationToken.None).ConfigureAwait(false);
-        }
-
-        public void Dispose()
-        {
-            _webSocket?.Dispose();
-        }
-    }
-}

Frameworks/MQTTnet.NetFramework/Implementations/WebSocketStream.cs

@@ -1,77 +0,0 @@
-using System;
-using System.IO;
-using System.Net.WebSockets;
-using System.Threading;
-using System.Threading.Tasks;
-
-namespace MQTTnet.Implementations
-{
-    public class WebSocketStream : Stream
-    {
-        private readonly ClientWebSocket _webSocket;
-
-        public WebSocketStream(ClientWebSocket webSocket)
-        {
-            _webSocket = webSocket;
-        }
-
-        public override void Flush()
-        {
-        }
-
-        public override async Task<int> ReadAsync(byte[] buffer, int offset, int count, CancellationToken cancellationToken)
-        {
-            var currentOffset = offset;
-            var targetOffset = offset + count;
-            while (_webSocket.State == WebSocketState.Open && currentOffset < targetOffset)
-            {
-                var response = await _webSocket.ReceiveAsync(new ArraySegment<byte>(buffer, currentOffset, count), cancellationToken).ConfigureAwait(false);
-                currentOffset += response.Count;
-
-                if (response.MessageType == WebSocketMessageType.Close)
-                {
-                    await _webSocket.CloseAsync(WebSocketCloseStatus.NormalClosure, string.Empty, cancellationToken).ConfigureAwait(false);
-                }
-            }
-
-            return currentOffset - offset;
-        }
-
-        public override Task WriteAsync(byte[] buffer, int offset, int count, CancellationToken cancellationToken)
-        {
-            return _webSocket.SendAsync(new ArraySegment<byte>(buffer, offset, count), WebSocketMessageType.Binary, true, cancellationToken);
-        }
-
-        public override int Read(byte[] buffer, int offset, int count)
-        {
-            return ReadAsync(buffer, offset, count).GetAwaiter().GetResult();
-        }
-
-        public override void Write(byte[] buffer, int offset, int count)
-        {
-            WriteAsync(buffer, offset, count).GetAwaiter().GetResult();
-        }
-
-        public override bool CanRead => true;
-        public override bool CanSeek => false;
-        public override bool CanWrite => true;
-
-        public override long Length => throw new NotSupportedException();
-
-        public override long Position
-        {
-            get => throw new NotSupportedException();
-            set => throw new NotSupportedException();
-        }
-
-        public override long Seek(long offset, SeekOrigin origin)
-        {
-            throw new NotSupportedException();
-        }
-
-        public override void SetLength(long value)
-        {
-            throw new NotSupportedException();
-        }
-    }
-}

Frameworks/MQTTnet.NetFramework/MQTTnet.NetFramework.csproj

@@ -1,125 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<Project ToolsVersion="14.0" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
-  <Import Project="$(MSBuildExtensionsPath)\$(MSBuildToolsVersion)\Microsoft.Common.props" Condition="Exists('$(MSBuildExtensionsPath)\$(MSBuildToolsVersion)\Microsoft.Common.props')" />
-  <PropertyGroup>
-    <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
-    <Platform Condition=" '$(Platform)' == '' ">AnyCPU</Platform>
-    <ProjectGuid>{A480EF90-0EAA-4D9A-B271-47A9C47F6F7D}</ProjectGuid>
-    <OutputType>Library</OutputType>
-    <AppDesignerFolder>Properties</AppDesignerFolder>
-    <RootNamespace>MQTTnet</RootNamespace>
-    <AssemblyName>MQTTnet</AssemblyName>
-    <TargetFrameworkVersion>v4.5</TargetFrameworkVersion>
-    <FileAlignment>512</FileAlignment>
-    <TargetFrameworkProfile />
-  </PropertyGroup>
-  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' ">
-    <DebugSymbols>true</DebugSymbols>
-    <DebugType>full</DebugType>
-    <Optimize>false</Optimize>
-    <OutputPath>bin\Debug\</OutputPath>
-    <DefineConstants>DEBUG;TRACE</DefineConstants>
-    <ErrorReport>prompt</ErrorReport>
-    <WarningLevel>4</WarningLevel>
-    <Prefer32Bit>false</Prefer32Bit>
-  </PropertyGroup>
-  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|AnyCPU' ">
-    <DebugType>pdbonly</DebugType>
-    <Optimize>true</Optimize>
-    <OutputPath>bin\Release\</OutputPath>
-    <DefineConstants>TRACE</DefineConstants>
-    <ErrorReport>prompt</ErrorReport>
-    <WarningLevel>4</WarningLevel>
-    <Prefer32Bit>false</Prefer32Bit>
-  </PropertyGroup>
-  <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Any CPU|AnyCPU'">
-    <OutputPath>bin\Any CPU\</OutputPath>
-    <DefineConstants>TRACE</DefineConstants>
-    <Optimize>true</Optimize>
-    <DebugType>pdbonly</DebugType>
-    <PlatformTarget>AnyCPU</PlatformTarget>
-    <ErrorReport>prompt</ErrorReport>
-    <CodeAnalysisRuleSet>MinimumRecommendedRules.ruleset</CodeAnalysisRuleSet>
-  </PropertyGroup>
-  <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Debug|x86'">
-    <DebugSymbols>true</DebugSymbols>
-    <OutputPath>bin\x86\Debug\</OutputPath>
-    <DefineConstants>DEBUG;TRACE</DefineConstants>
-    <DebugType>full</DebugType>
-    <PlatformTarget>x86</PlatformTarget>
-    <ErrorReport>prompt</ErrorReport>
-    <CodeAnalysisRuleSet>MinimumRecommendedRules.ruleset</CodeAnalysisRuleSet>
-  </PropertyGroup>
-  <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Release|x86'">
-    <OutputPath>bin\x86\Release\</OutputPath>
-    <DefineConstants>TRACE</DefineConstants>
-    <Optimize>true</Optimize>
-    <DebugType>pdbonly</DebugType>
-    <PlatformTarget>x86</PlatformTarget>
-    <ErrorReport>prompt</ErrorReport>
-    <CodeAnalysisRuleSet>MinimumRecommendedRules.ruleset</CodeAnalysisRuleSet>
-  </PropertyGroup>
-  <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Any CPU|x86'">
-    <OutputPath>bin\x86\Any CPU\</OutputPath>
-    <DefineConstants>TRACE</DefineConstants>
-    <Optimize>true</Optimize>
-    <DebugType>pdbonly</DebugType>
-    <PlatformTarget>x86</PlatformTarget>
-    <ErrorReport>prompt</ErrorReport>
-    <CodeAnalysisRuleSet>MinimumRecommendedRules.ruleset</CodeAnalysisRuleSet>
-  </PropertyGroup>
-  <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Debug|x64'">
-    <DebugSymbols>true</DebugSymbols>
-    <OutputPath>bin\x64\Debug\</OutputPath>
-    <DefineConstants>DEBUG;TRACE</DefineConstants>
-    <DebugType>full</DebugType>
-    <PlatformTarget>x64</PlatformTarget>
-    <ErrorReport>prompt</ErrorReport>
-    <CodeAnalysisRuleSet>MinimumRecommendedRules.ruleset</CodeAnalysisRuleSet>
-  </PropertyGroup>
-  <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Release|x64'">
-    <OutputPath>bin\x64\Release\</OutputPath>
-    <DefineConstants>TRACE</DefineConstants>
-    <Optimize>true</Optimize>
-    <DebugType>pdbonly</DebugType>
-    <PlatformTarget>x64</PlatformTarget>
-    <ErrorReport>prompt</ErrorReport>
-    <CodeAnalysisRuleSet>MinimumRecommendedRules.ruleset</CodeAnalysisRuleSet>
-  </PropertyGroup>
-  <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Any CPU|x64'">
-    <OutputPath>bin\x64\Any CPU\</OutputPath>
-    <DefineConstants>TRACE</DefineConstants>
-    <Optimize>true</Optimize>
-    <DebugType>pdbonly</DebugType>
-    <PlatformTarget>x64</PlatformTarget>
-    <ErrorReport>prompt</ErrorReport>
-    <CodeAnalysisRuleSet>MinimumRecommendedRules.ruleset</CodeAnalysisRuleSet>
-  </PropertyGroup>
-  <ItemGroup>
-    <Reference Include="System" />
-    <Reference Include="System.Core" />
-  </ItemGroup>
-  <ItemGroup>
-    <Compile Include="Implementations\MqttWebSocketChannel.cs" />
-    <Compile Include="Implementations\WebSocketStream.cs" />
-    <Compile Include="MqttClientFactory.cs" />
-    <Compile Include="MqttServerFactory.cs" />
-    <Compile Include="Implementations\MqttServerAdapter.cs" />
-    <Compile Include="Properties\AssemblyInfo.cs" />
-    <Compile Include="Implementations\MqttTcpChannel.cs" />
-  </ItemGroup>
-  <ItemGroup>
-    <ProjectReference Include="..\..\MQTTnet.Core\MQTTnet.Core.csproj">
-      <Project>{2ecb99e4-72d0-4c23-99ba-93d511d3967d}</Project>
-      <Name>MQTTnet.Core</Name>
-    </ProjectReference>
-  </ItemGroup>
-  <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
-  <!-- To modify your build process, add your task inside one of the targets below and uncomment it. 
-       Other similar extension points exist, see Microsoft.Common.targets.
-  <Target Name="BeforeBuild">
-  </Target>
-  <Target Name="AfterBuild">
-  </Target>
-  -->
-</Project>

Frameworks/MQTTnet.NetFramework/MqttClientFactory.cs

@@ -1,33 +0,0 @@
-using System;
-using MQTTnet.Core.Adapter;
-using MQTTnet.Core.Channel;
-using MQTTnet.Core.Client;
-using MQTTnet.Core.Serializer;
-using MQTTnet.Implementations;
-
-namespace MQTTnet
-{
-    public class MqttClientFactory : IMqttClientFactory
-    {
-        public IMqttClient CreateMqttClient(MqttClientOptions options)
-        {
-            if (options == null) throw new ArgumentNullException(nameof(options));
-
-            return new MqttClient(options, new MqttChannelCommunicationAdapter(GetMqttCommunicationChannel(options), new MqttPacketSerializer()));
-        }
-
-        private static IMqttCommunicationChannel GetMqttCommunicationChannel(MqttClientOptions options)
-        {
-            switch (options.ConnectionType)
-            {
-                case MqttConnectionType.Tcp:
-                    return new MqttTcpChannel();
-                case MqttConnectionType.Ws:
-                    return new MqttWebSocketChannel();
-
-                default:
-                    throw new NotSupportedException();
-            }
-        }
-    }
-}

Frameworks/MQTTnet.NetFramework/MqttServerFactory.cs

@@ -1,18 +0,0 @@
-using System;
-using System.Collections.Generic;
-using MQTTnet.Core.Adapter;
-using MQTTnet.Core.Server;
-using MQTTnet.Implementations;
-
-namespace MQTTnet
-{
-    public class MqttServerFactory : IMqttServerFactory
-    {
-        public IMqttServer CreateMqttServer(MqttServerOptions options)
-        {
-            if (options == null) throw new ArgumentNullException(nameof(options));
-
-            return new MqttServer(options, new List<IMqttServerAdapter> { new MqttServerAdapter() });
-        }
-    }
-}

Frameworks/MQTTnet.NetFramework/Properties/AssemblyInfo.cs

@@ -1,15 +0,0 @@
-using System.Reflection;
-using System.Runtime.InteropServices;
-
-[assembly: AssemblyTitle("MQTTnet")]
-[assembly: AssemblyDescription("MQTTnet for .NET Framework")]
-[assembly: AssemblyConfiguration("")]
-[assembly: AssemblyCompany("Christian Kratky")]
-[assembly: AssemblyProduct("MQTTnet")]
-[assembly: AssemblyCopyright("Copyright © Christian Kratky 2016-2017")]
-[assembly: AssemblyTrademark("")]
-[assembly: AssemblyCulture("")]
-[assembly: ComVisible(false)]
-[assembly: Guid("a480ef90-0eaa-4d9a-b271-47a9c47f6f7d")]
-[assembly: AssemblyVersion("2.3.0.0")]
-[assembly: AssemblyFileVersion("2.3.0.0")]

Frameworks/MQTTnet.NetStandard/Implementations/MqttServerAdapter.Uwp.cs

@@ -0,0 +1,76 @@
+#if WINDOWS_UWP
+using System;
+using System.Threading.Tasks;
+using MQTTnet.Core.Adapter;
+using MQTTnet.Core.Server;
+using Windows.Networking.Sockets;
+using Microsoft.Extensions.Logging;
+
+namespace MQTTnet.Implementations
+{
+    public class MqttServerAdapter : IMqttServerAdapter, IDisposable
+    {
+        private readonly ILogger<MqttServerAdapter> _logger;
+        private readonly IMqttCommunicationAdapterFactory _communicationAdapterFactory;
+        private StreamSocketListener _defaultEndpointSocket;
+
+        public MqttServerAdapter(ILogger<MqttServerAdapter> logger, IMqttCommunicationAdapterFactory communicationAdapterFactory)
+        {
+            _logger = logger ?? throw new ArgumentNullException(nameof(logger));
+            _communicationAdapterFactory = communicationAdapterFactory ?? throw new ArgumentNullException(nameof(communicationAdapterFactory));
+        }
+
+        public event EventHandler<MqttServerAdapterClientAcceptedEventArgs> ClientAccepted;
+
+        public async Task StartAsync(MqttServerOptions options)
+        {
+            if (options == null) throw new ArgumentNullException(nameof(options));
+
+            if (_defaultEndpointSocket != null) throw new InvalidOperationException("Server is already started.");
+            
+            if (options.DefaultEndpointOptions.IsEnabled)
+            {
+                _defaultEndpointSocket = new StreamSocketListener();
+                await _defaultEndpointSocket.BindServiceNameAsync(options.GetDefaultEndpointPort().ToString(), SocketProtectionLevel.PlainSocket);
+                _defaultEndpointSocket.ConnectionReceived += AcceptDefaultEndpointConnectionsAsync;
+            }
+
+            if (options.TlsEndpointOptions.IsEnabled)
+            {
+                throw new NotSupportedException("TLS servers are not supported for UWP apps.");
+            }
+        }
+
+        public Task StopAsync()
+        {
+            if (_defaultEndpointSocket != null)
+            {
+                _defaultEndpointSocket.ConnectionReceived -= AcceptDefaultEndpointConnectionsAsync;
+            }
+
+            _defaultEndpointSocket?.Dispose();
+            _defaultEndpointSocket = null;
+
+            return Task.FromResult(0);
+        }
+
+        public void Dispose()
+        {
+            StopAsync();
+        }
+
+        private void AcceptDefaultEndpointConnectionsAsync(StreamSocketListener sender, StreamSocketListenerConnectionReceivedEventArgs args)
+        {
+            try
+            {
+                var clientAdapter = _communicationAdapterFactory.CreateServerCommunicationAdapter(new MqttTcpChannel(args.Socket));
+                ClientAccepted?.Invoke(this, new MqttServerAdapterClientAcceptedEventArgs(clientAdapter));
+            }
+            catch (Exception exception)
+            {
+                _logger.LogError(new EventId(), exception, "Error while accepting connection at default endpoint.");
+            }
+        }
+    }
+}
+#endif

Frameworks/MQTTnet.NetStandard/Implementations/MqttServerAdapter.cs

@@ -1,4 +1,5 @@
-using System;
+#if NET452 || NETSTANDARD1_3
+using System;
 using System.Net;
 using System.Net.Security;
 using System.Net.Sockets;
@@ -7,28 +8,32 @@ using System.Security.Cryptography.X509Certificates;
 using System.Threading;
 using System.Threading.Tasks;
 using MQTTnet.Core.Adapter;
-using MQTTnet.Core.Diagnostics;
-using MQTTnet.Core.Serializer;
 using MQTTnet.Core.Server;
+using Microsoft.Extensions.Logging;
 
 namespace MQTTnet.Implementations
 {
     public class MqttServerAdapter : IMqttServerAdapter, IDisposable
     {
+        private readonly ILogger<MqttServerAdapter> _logger;
+        private readonly IMqttCommunicationAdapterFactory _communicationAdapterFactory;
+
         private CancellationTokenSource _cancellationTokenSource;
         private Socket _defaultEndpointSocket;
         private Socket _tlsEndpointSocket;
         private X509Certificate2 _tlsCertificate;
 
-        private bool _isRunning;
-
-        public event EventHandler<MqttClientConnectedEventArgs> ClientConnected;
-
-        public void Start(MqttServerOptions options)
+        public MqttServerAdapter(ILogger<MqttServerAdapter> logger, IMqttCommunicationAdapterFactory communicationAdapterFactory)
         {
-            if (_isRunning) throw new InvalidOperationException("Server is already started.");
+            _logger = logger ?? throw new ArgumentNullException(nameof(logger));
+            _communicationAdapterFactory = communicationAdapterFactory ?? throw new ArgumentNullException(nameof(communicationAdapterFactory));
+        }
 
-            _isRunning = true;
+        public event EventHandler<MqttServerAdapterClientAcceptedEventArgs> ClientAccepted;
+
+        public Task StartAsync(MqttServerOptions options)
+        {
+            if (_cancellationTokenSource != null) throw new InvalidOperationException("Server is already started.");
 
             _cancellationTokenSource = new CancellationTokenSource();
 
@@ -49,6 +54,10 @@ namespace MQTTnet.Implementations
                 }
 
                 _tlsCertificate = new X509Certificate2(options.TlsEndpointOptions.Certificate);
+                if (!_tlsCertificate.HasPrivateKey)
+                {
+                    throw new InvalidOperationException("The certificate for TLS encryption must contain the private key.");
+                }
 
                 _tlsEndpointSocket = new Socket(SocketType.Stream, ProtocolType.Tcp);
                 _tlsEndpointSocket.Bind(new IPEndPoint(IPAddress.Any, options.GetTlsEndpointPort()));
@@ -56,12 +65,12 @@ namespace MQTTnet.Implementations
 
                 Task.Run(() => AcceptTlsEndpointConnectionsAsync(_cancellationTokenSource.Token), _cancellationTokenSource.Token);
             }
+
+            return Task.FromResult(0);
         }
 
-        public void Stop()
+        public Task StopAsync()
         {
-            _isRunning = false;
-
             _cancellationTokenSource?.Cancel(false);
             _cancellationTokenSource?.Dispose();
             _cancellationTokenSource = null;
@@ -69,13 +78,17 @@ namespace MQTTnet.Implementations
             _defaultEndpointSocket?.Dispose();
             _defaultEndpointSocket = null;
 
+            _tlsCertificate = null;
+            
             _tlsEndpointSocket?.Dispose();
             _tlsEndpointSocket = null;
+
+            return Task.FromResult(0);
         }
 
         public void Dispose()
         {
-            Stop();
+            StopAsync();
         }
 
         private async Task AcceptDefaultEndpointConnectionsAsync(CancellationToken cancellationToken)
@@ -84,13 +97,18 @@ namespace MQTTnet.Implementations
             {
                 try
                 {
+                    //todo: else branch can be used with min dependency NET46
+#if NET452
+                    var clientSocket = await Task.Factory.FromAsync(_defaultEndpointSocket.BeginAccept, _defaultEndpointSocket.EndAccept, null).ConfigureAwait(false);
+#else
                     var clientSocket = await _defaultEndpointSocket.AcceptAsync().ConfigureAwait(false);
-                    var clientAdapter = new MqttChannelCommunicationAdapter(new MqttTcpChannel(clientSocket, null), new MqttPacketSerializer());
-                    ClientConnected?.Invoke(this, new MqttClientConnectedEventArgs(clientSocket.RemoteEndPoint.ToString(), clientAdapter));
+#endif
+                    var clientAdapter = _communicationAdapterFactory.CreateServerCommunicationAdapter(new MqttTcpChannel(clientSocket, null));
+                    ClientAccepted?.Invoke(this, new MqttServerAdapterClientAcceptedEventArgs(clientAdapter));
                 }
                 catch (Exception exception)
                 {
-                    MqttTrace.Error(nameof(MqttServerAdapter), exception, "Error while accepting connection at default endpoint.");
+                    _logger.LogError(new EventId(), exception, "Error while accepting connection at default endpoint.");
 
                     //excessive CPU consumed if in endless loop of socket errors
                     await Task.Delay(TimeSpan.FromSeconds(1), cancellationToken).ConfigureAwait(false);
@@ -104,17 +122,21 @@ namespace MQTTnet.Implementations
             {
                 try
                 {
+#if NET452
+                    var clientSocket = await Task.Factory.FromAsync(_tlsEndpointSocket.BeginAccept, _tlsEndpointSocket.EndAccept, null).ConfigureAwait(false);
+#else
                     var clientSocket = await _tlsEndpointSocket.AcceptAsync().ConfigureAwait(false);
+#endif
 
                     var sslStream = new SslStream(new NetworkStream(clientSocket));
                     await sslStream.AuthenticateAsServerAsync(_tlsCertificate, false, SslProtocols.Tls12, false).ConfigureAwait(false);
 
-                    var clientAdapter = new MqttChannelCommunicationAdapter(new MqttTcpChannel(clientSocket, sslStream), new MqttPacketSerializer());
-                    ClientConnected?.Invoke(this, new MqttClientConnectedEventArgs(clientSocket.RemoteEndPoint.ToString(), clientAdapter));
+                    var clientAdapter = _communicationAdapterFactory.CreateServerCommunicationAdapter(new MqttTcpChannel(clientSocket, sslStream));
+                    ClientAccepted?.Invoke(this, new MqttServerAdapterClientAcceptedEventArgs(clientAdapter));
                 }
                 catch (Exception exception)
                 {
-                    MqttTrace.Error(nameof(MqttServerAdapter), exception, "Error while accepting connection at TLS endpoint.");
+                    _logger.LogError(new EventId(), exception, "Error while accepting connection at TLS endpoint.");
 
                     //excessive CPU consumed if in endless loop of socket errors
                     await Task.Delay(TimeSpan.FromSeconds(1), cancellationToken).ConfigureAwait(false);
@@ -122,4 +144,5 @@ namespace MQTTnet.Implementations
             }
         }
     }
-}
+}
+#endif

Frameworks/MQTTnet.NetStandard/Implementations/MqttTcpChannel.Uwp.cs

@@ -0,0 +1,133 @@
+#if WINDOWS_UWP
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Runtime.InteropServices.WindowsRuntime;
+using System.Threading.Tasks;
+using Windows.Networking;
+using Windows.Networking.Sockets;
+using Windows.Security.Cryptography.Certificates;
+using MQTTnet.Core.Channel;
+using MQTTnet.Core.Client;
+
+namespace MQTTnet.Implementations
+{
+    public sealed class MqttTcpChannel : IMqttCommunicationChannel, IDisposable
+    {
+        private readonly MqttClientTcpOptions _options;
+        private StreamSocket _socket;
+
+        public MqttTcpChannel(MqttClientTcpOptions options)
+        {
+            _options = options ?? throw new ArgumentNullException(nameof(options));
+        }
+
+        public MqttTcpChannel(StreamSocket socket)
+        {
+            _socket = socket ?? throw new ArgumentNullException(nameof(socket));
+
+            CreateStreams();
+        }
+
+        public Stream SendStream { get; private set; }
+        public Stream ReceiveStream { get; private set; }
+
+        public static Func<MqttClientTcpOptions, IEnumerable<ChainValidationResult>> CustomIgnorableServerCertificateErrorsResolver { get; set; }
+
+        public async Task ConnectAsync()
+        {
+            if (_socket == null)
+            {
+                _socket = new StreamSocket();
+            }
+
+            if (!_options.TlsOptions.UseTls)
+            {
+                await _socket.ConnectAsync(new HostName(_options.Server), _options.GetPort().ToString());
+            }
+            else
+            {
+                _socket.Control.ClientCertificate = LoadCertificate(_options);
+
+                foreach (var ignorableChainValidationResult in ResolveIgnorableServerCertificateErrors())
+                {
+                    _socket.Control.IgnorableServerCertificateErrors.Add(ignorableChainValidationResult);
+                }
+
+                await _socket.ConnectAsync(new HostName(_options.Server), _options.GetPort().ToString(), SocketProtectionLevel.Tls12);
+            }
+
+            CreateStreams();
+        }
+
+        public Task DisconnectAsync()
+        {
+            Dispose();
+            return Task.FromResult(0);
+        }
+
+        public void Dispose()
+        {
+            SendStream?.Dispose();
+            SendStream = null;
+
+            ReceiveStream?.Dispose();
+            ReceiveStream = null;
+
+            _socket?.Dispose();
+            _socket = null;
+        }
+
+        private void CreateStreams()
+        {
+            SendStream = _socket.OutputStream.AsStreamForWrite();
+            ReceiveStream = _socket.InputStream.AsStreamForRead();
+        }
+
+        private static Certificate LoadCertificate(MqttClientTcpOptions options)
+        {
+            if (options.TlsOptions.Certificates == null || !options.TlsOptions.Certificates.Any())
+            {
+                return null;
+            }
+
+            if (options.TlsOptions.Certificates.Count > 1)
+            {
+                throw new NotSupportedException("Only one client certificate is supported for UWP.");
+            }
+
+            return new Certificate(options.TlsOptions.Certificates.First().AsBuffer());
+        }
+
+        private IEnumerable<ChainValidationResult> ResolveIgnorableServerCertificateErrors()
+        {
+            if (CustomIgnorableServerCertificateErrorsResolver != null)
+            {
+                return CustomIgnorableServerCertificateErrorsResolver(_options);
+            }
+
+            var result = new List<ChainValidationResult>();
+
+            if (_options.TlsOptions.IgnoreCertificateRevocationErrors)
+            {
+                result.Add(ChainValidationResult.RevocationInformationMissing);
+                //_socket.Control.IgnorableServerCertificateErrors.Add(ChainValidationResult.Revoked); Not supported.
+                result.Add(ChainValidationResult.RevocationFailure);
+            }
+
+            if (_options.TlsOptions.IgnoreCertificateChainErrors)
+            {
+                result.Add(ChainValidationResult.IncompleteChain);
+            }
+
+            if (_options.TlsOptions.AllowUntrustedCertificates)
+            {
+                result.Add(ChainValidationResult.Untrusted);
+            }
+
+            return result;
+        }
+    }
+}
+#endif

Frameworks/MQTTnet.NetStandard/Implementations/MqttTcpChannel.cs

@@ -1,3 +1,4 @@
+#if NET452 || NETSTANDARD1_3
 using System;
 using System.Net.Security;
 using System.Net.Sockets;
@@ -7,19 +8,30 @@ using System.Threading.Tasks;
 using MQTTnet.Core.Channel;
 using MQTTnet.Core.Client;
 using System.IO;
+using System.Linq;
 
 namespace MQTTnet.Implementations
 {
     public sealed class MqttTcpChannel : IMqttCommunicationChannel, IDisposable
     {
+        private readonly MqttClientTcpOptions _options;
+
+        //todo: this can be used with min dependency NetStandard1.6
+#if NET452
+        // ReSharper disable once MemberCanBePrivate.Global
+        // ReSharper disable once AutoPropertyCanBeMadeGetOnly.Global
+        public static int BufferSize { get; set; } = 4096 * 20; // Can be changed for fine tuning by library user.
+#endif
+
         private Socket _socket;
         private SslStream _sslStream;
-        
+
         /// <summary>
         /// called on client sockets are created in connect
         /// </summary>
-        public MqttTcpChannel()
+        public MqttTcpChannel(MqttClientTcpOptions options)
         {
+            _options = options ?? throw new ArgumentNullException(nameof(options));
         }
 
         /// <summary>
@@ -30,34 +42,36 @@ namespace MQTTnet.Implementations
         {
             _socket = socket ?? throw new ArgumentNullException(nameof(socket));
             _sslStream = sslStream;
-            ReceiveStream = (Stream)sslStream ?? new NetworkStream(socket);
+
+            CreateStreams(socket, sslStream);
         }
 
-        public Stream SendStream => ReceiveStream;
+        public Stream SendStream { get; private set; }
         public Stream ReceiveStream { get; private set; }
-        public Stream RawReceiveStream => ReceiveStream;
-        
-        public async Task ConnectAsync(MqttClientOptions options)
-        {
-            if (options == null) throw new ArgumentNullException(nameof(options));
 
+        public static Func<X509Certificate, X509Chain, SslPolicyErrors, MqttClientTcpOptions, bool> CustomCertificateValidationCallback { get; set; }
+
+        public async Task ConnectAsync()
+        {
             if (_socket == null)
             {
                 _socket = new Socket(SocketType.Stream, ProtocolType.Tcp);
             }
 
-            await _socket.ConnectAsync(options.Server, options.GetPort()).ConfigureAwait(false);
+            //todo: else brach can be used with min dependency NET46
+#if NET452
+            await Task.Factory.FromAsync(_socket.BeginConnect, _socket.EndConnect, _options.Server, _options.GetPort(), null).ConfigureAwait(false);
+#else
+            await _socket.ConnectAsync(_options.Server, _options.GetPort()).ConfigureAwait(false);
+#endif
 
-            if (options.TlsOptions.UseTls)
+            if (_options.TlsOptions.UseTls)
             {
-                _sslStream = new SslStream(new NetworkStream(_socket, true));
-                ReceiveStream = _sslStream;
-                await _sslStream.AuthenticateAsClientAsync(options.Server, LoadCertificates(options), SslProtocols.Tls12, options.TlsOptions.CheckCertificateRevocation).ConfigureAwait(false);
-            }
-            else
-            {
-                ReceiveStream = new NetworkStream(_socket);
+                _sslStream = new SslStream(new NetworkStream(_socket, true), false, InternalUserCertificateValidationCallback);
+                await _sslStream.AuthenticateAsClientAsync(_options.Server, LoadCertificates(_options), SslProtocols.Tls12, _options.TlsOptions.IgnoreCertificateRevocationErrors).ConfigureAwait(false);
             }
+
+            CreateStreams(_socket, _sslStream);
         }
 
         public Task DisconnectAsync()
@@ -75,7 +89,38 @@ namespace MQTTnet.Implementations
             _sslStream = null;
         }
 
-        private static X509CertificateCollection LoadCertificates(MqttClientOptions options)
+        private bool InternalUserCertificateValidationCallback(object sender, X509Certificate x509Certificate, X509Chain chain, SslPolicyErrors sslPolicyErrors)
+        {
+            if (CustomCertificateValidationCallback != null)
+            {
+                return CustomCertificateValidationCallback(x509Certificate, chain, sslPolicyErrors, _options);
+            }
+
+            if (sslPolicyErrors == SslPolicyErrors.None)
+            {
+                return true;
+            }
+
+            if (chain.ChainStatus.Any(c => c.Status == X509ChainStatusFlags.RevocationStatusUnknown || c.Status == X509ChainStatusFlags.Revoked || c.Status == X509ChainStatusFlags.RevocationStatusUnknown))
+            {
+                if (!_options.TlsOptions.IgnoreCertificateRevocationErrors)
+                {
+                    return false;
+                }
+            }
+
+            if (chain.ChainStatus.Any(c => c.Status == X509ChainStatusFlags.PartialChain))
+            {
+                if (!_options.TlsOptions.IgnoreCertificateChainErrors)
+                {
+                    return false;
+                }
+            }
+
+            return _options.TlsOptions.AllowUntrustedCertificates;
+        }
+
+        private static X509CertificateCollection LoadCertificates(MqttClientTcpOptions options)
         {
             var certificates = new X509CertificateCollection();
             if (options.TlsOptions.Certificates == null)
@@ -90,5 +135,24 @@ namespace MQTTnet.Implementations
 
             return certificates;
         }
+
+        private void CreateStreams(Socket socket, Stream sslStream)
+        {
+            var stream = sslStream ?? new NetworkStream(socket);
+
+            //cannot use this as default buffering prevents from receiving the first connect message
+            //need two streams otherwise read and write have to be synchronized
+
+            //todo: if branch can be used with min dependency NetStandard1.6
+#if NET452
+            SendStream = new BufferedStream(stream, BufferSize);
+            ReceiveStream = new BufferedStream(stream, BufferSize);
+#else
+            SendStream = stream;
+            ReceiveStream = stream;
+#endif
+        }
+
     }
-}
+}
+#endif

Frameworks/MQTTnet.NetStandard/Implementations/MqttWebSocketChannel.cs

@@ -3,6 +3,7 @@ using MQTTnet.Core.Client;
 using System;
 using System.IO;
 using System.Net.WebSockets;
+using System.Security.Cryptography.X509Certificates;
 using System.Threading;
 using System.Threading.Tasks;
 
@@ -10,28 +11,59 @@ namespace MQTTnet.Implementations
 {
     public sealed class MqttWebSocketChannel : IMqttCommunicationChannel, IDisposable
     {
+        private readonly MqttClientWebSocketOptions _options;
         private ClientWebSocket _webSocket;
 
+        public MqttWebSocketChannel(MqttClientWebSocketOptions options)
+        {
+            _options = options ?? throw new ArgumentNullException(nameof(options));
+        }
+
         public Stream SendStream => RawReceiveStream;
         public Stream ReceiveStream => RawReceiveStream;
         public Stream RawReceiveStream { get; private set; }
 
-        public async Task ConnectAsync(MqttClientOptions options)
+        public async Task ConnectAsync()
         {
-            var uri = options.Server;
+            var uri = _options.Uri;
             if (!uri.StartsWith("ws://", StringComparison.OrdinalIgnoreCase))
             {
                 uri = "ws://" + uri;
             }
 
-            if (options.Port.HasValue)
-            {
-                uri += ":" + options.Port;
-            }
-            
             _webSocket = new ClientWebSocket();
-            _webSocket.Options.KeepAliveInterval = options.KeepAlivePeriod;
-            await _webSocket.ConnectAsync(new Uri(uri), CancellationToken.None);
+
+            if (_options.RequestHeaders != null)
+            {
+                foreach (var requestHeader in _options.RequestHeaders)
+                {
+                    _webSocket.Options.SetRequestHeader(requestHeader.Key, requestHeader.Value);
+                }    
+            }
+
+            if (_options.SubProtocols != null)
+            {
+                foreach (var subProtocol in _options.SubProtocols)
+                {
+                    _webSocket.Options.AddSubProtocol(subProtocol);
+                }
+            }
+
+            if (_options.CookieContainer != null)
+            {
+                _webSocket.Options.Cookies = _options.CookieContainer;
+            }
+
+            if (_options.TlsOptions?.UseTls == true && _options.TlsOptions?.Certificates != null)
+            {
+                _webSocket.Options.ClientCertificates = new X509CertificateCollection();
+                foreach (var certificate in _options.TlsOptions.Certificates)
+                {
+                    _webSocket.Options.ClientCertificates.Add(new X509Certificate(certificate));
+                }
+            }
+
+            await _webSocket.ConnectAsync(new Uri(uri), CancellationToken.None).ConfigureAwait(false);
             RawReceiveStream = new WebSocketStream(_webSocket);
         }
 
@@ -44,12 +76,16 @@ namespace MQTTnet.Implementations
                 return;
             }
 
-            await _webSocket.CloseAsync(WebSocketCloseStatus.NormalClosure, string.Empty, CancellationToken.None).ConfigureAwait(false);
+            if (_webSocket.State == WebSocketState.Open || _webSocket.State == WebSocketState.Connecting)
+            {
+                await _webSocket.CloseAsync(WebSocketCloseStatus.NormalClosure, string.Empty, CancellationToken.None).ConfigureAwait(false);
+            }
         }
 
         public void Dispose()
         {
             _webSocket?.Dispose();
+            _webSocket = null;
         }
     }
 }

Frameworks/MQTTnet.NetStandard/Implementations/WebSocketStream.cs

@@ -3,16 +3,17 @@ using System.IO;
 using System.Net.WebSockets;
 using System.Threading;
 using System.Threading.Tasks;
+using MQTTnet.Core.Exceptions;
 
 namespace MQTTnet.Implementations
 {
     public class WebSocketStream : Stream
     {
-        private readonly ClientWebSocket _webSocket;
+        private readonly WebSocket _webSocket;
         
-        public WebSocketStream(ClientWebSocket webSocket)
+        public WebSocketStream(WebSocket webSocket)
         {
-            _webSocket = webSocket;
+            _webSocket = webSocket ?? throw new ArgumentNullException(nameof(webSocket));
         }
 
         public override bool CanRead => true;
@@ -41,6 +42,7 @@ namespace MQTTnet.Implementations
             {
                 var response = await _webSocket.ReceiveAsync(new ArraySegment<byte>(buffer, currentOffset, count), cancellationToken).ConfigureAwait(false);
                 currentOffset += response.Count;
+                count -= response.Count;
 
                 if (response.MessageType == WebSocketMessageType.Close)
                 {
@@ -48,6 +50,11 @@ namespace MQTTnet.Implementations
                 }
             }
 
+            if (_webSocket.State == WebSocketState.Closed)
+            {
+                throw new MqttCommunicationException( "connection closed" );
+            }
+
             return currentOffset - offset;
         }
 

Frameworks/MQTTnet.NetStandard/MQTTnet.Netstandard.csproj

@@ -1,11 +1,11 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>netstandard1.3</TargetFramework>
+    <TargetFrameworks>netstandard1.3;net452;uap10.0</TargetFrameworks>
     <AssemblyName>MQTTnet</AssemblyName>
     <RootNamespace>MQTTnet</RootNamespace>
-    <AssemblyVersion>2.3.0.0</AssemblyVersion>
-    <FileVersion>2.3.0.0</FileVersion>
+    <AssemblyVersion>2.5.0.0</AssemblyVersion>
+    <FileVersion>2.5.0.0</FileVersion>
     <Version>0.0.0.0</Version>
     <Company />
     <Product />
@@ -14,19 +14,41 @@
     <PackageId />
   </PropertyGroup>
 
+  <PropertyGroup Condition="'$(TargetFramework)' == 'uap10.0'">
+    <CopyLocalLockFileAssemblies>false</CopyLocalLockFileAssemblies>
+    <NugetTargetMoniker>UAP,Version=v10.0</NugetTargetMoniker>
+    <TargetPlatformIdentifier>UAP</TargetPlatformIdentifier>
+    <TargetPlatformVersion>10.0.16299.0</TargetPlatformVersion>
+    <TargetPlatformMinVersion>10.0.10240.0</TargetPlatformMinVersion>
+    <TargetFrameworkIdentifier>.NETCore</TargetFrameworkIdentifier>
+    <TargetFrameworkVersion>v5.0</TargetFrameworkVersion>
+    <DefineConstants>$(DefineConstants);WINDOWS_UWP</DefineConstants>
+    <LanguageTargets>$(MSBuildExtensionsPath)\Microsoft\WindowsXaml\v$(VisualStudioVersion)\Microsoft.Windows.UI.Xaml.CSharp.targets</LanguageTargets>
+    
+  </PropertyGroup>
+
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|x86'" />
 
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|x64'" />
 
   <ItemGroup>
-    <ProjectReference Include="..\..\MQTTnet.Core\MQTTnet.Core.csproj" />
+    <PackageReference Include="Microsoft.Extensions.DependencyInjection" Version="1.1.1" />
+    <PackageReference Include="Microsoft.Extensions.Logging" Version="1.1.2" />
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="System.Net.Security" Version="4.3.1" />
+    <ProjectReference Include="..\..\MQTTnet.Core\MQTTnet.Core.csproj" />
+  </ItemGroup>
+
+  <ItemGroup Condition="'$(TargetFramework)'=='netstandard1.3'">
+    <PackageReference Include="System.Net.Security" Version="4.3.2" />
     <PackageReference Include="System.Net.WebSockets" Version="4.3.0" />
     <PackageReference Include="System.Net.WebSockets.Client" Version="4.3.1" />
     <PackageReference Include="System.Threading.Thread" Version="4.3.0" />
   </ItemGroup>
 
+  <ItemGroup Condition="'$(TargetFramework)'=='uap10.0'">
+    <PackageReference Include="Microsoft.NETCore.UniversalWindowsPlatform" Version="5.4.0" />
+  </ItemGroup>
+
 </Project>

Frameworks/MQTTnet.NetStandard/MqttClientFactory.cs

@@ -1,33 +0,0 @@
-using System;
-using MQTTnet.Core.Adapter;
-using MQTTnet.Core.Channel;
-using MQTTnet.Core.Client;
-using MQTTnet.Core.Serializer;
-using MQTTnet.Implementations;
-
-namespace MQTTnet
-{
-    public class MqttClientFactory : IMqttClientFactory
-    {
-        public IMqttClient CreateMqttClient(MqttClientOptions options)
-        {
-            if (options == null) throw new ArgumentNullException(nameof(options));
-
-            return new MqttClient(options, new MqttChannelCommunicationAdapter(GetMqttCommunicationChannel(options), new MqttPacketSerializer()));
-        }
-
-        private static IMqttCommunicationChannel GetMqttCommunicationChannel(MqttClientOptions options)
-        {
-            switch (options.ConnectionType)
-            {
-                case MqttConnectionType.Tcp:
-                    return new MqttTcpChannel();
-                case MqttConnectionType.Ws:
-                    return new MqttWebSocketChannel();
-
-                default:
-                    throw new NotSupportedException();
-            }
-        }
-    }
-}

Frameworks/MQTTnet.NetStandard/MqttFactory.cs

@@ -0,0 +1,132 @@
+using System;
+using MQTTnet.Core.Adapter;
+using MQTTnet.Core.Client;
+using MQTTnet.Core.Serializer;
+using Microsoft.Extensions.Logging;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Options;
+using MQTTnet.Implementations;
+using MQTTnet.Core.ManagedClient;
+using MQTTnet.Core.Server;
+using MQTTnet.Core.Channel;
+
+namespace MQTTnet
+{
+    public class MqttFactory : IMqttCommunicationAdapterFactory, IMqttClientSesssionFactory, IMqttClientFactory, IMqttServerFactory
+    {
+        private readonly IServiceProvider _serviceProvider;
+
+        private static IServiceProvider BuildServiceProvider()
+        {
+            var serviceProvider = new ServiceCollection()
+                .AddMqttClient()
+                .AddMqttServer()
+                .AddLogging()
+                .BuildServiceProvider();
+
+            serviceProvider.GetRequiredService<ILoggerFactory>()
+                .AddMqttTrace();
+
+            return serviceProvider;
+        }
+
+        public MqttFactory()
+            : this(BuildServiceProvider())
+        {
+        }
+
+        public MqttFactory(IServiceProvider serviceProvider)
+        {
+            _serviceProvider = serviceProvider;
+        }
+
+        public ILoggerFactory GetLoggerFactory()
+        {
+            return _serviceProvider.GetRequiredService<ILoggerFactory>();
+        }
+
+        public IMqttCommunicationAdapter CreateClientCommunicationAdapter(IMqttClientOptions options)
+        {
+            var logger = _serviceProvider.GetRequiredService<ILogger<MqttChannelCommunicationAdapter>>();
+            return new MqttChannelCommunicationAdapter(CreateCommunicationChannel(options.ChannelOptions), CreateSerializer(options.ProtocolVersion), logger);
+        }
+
+        public IMqttCommunicationAdapter CreateServerCommunicationAdapter(IMqttCommunicationChannel channel)
+        {
+            var serializer = _serviceProvider.GetRequiredService<IMqttPacketSerializer>();
+            var logger = _serviceProvider.GetRequiredService<ILogger<MqttChannelCommunicationAdapter>>();
+            return new MqttChannelCommunicationAdapter(channel, serializer, logger);
+        }
+
+        public IMqttCommunicationChannel CreateCommunicationChannel(IMqttClientChannelOptions options)
+        {
+            if (options == null) throw new ArgumentNullException(nameof(options));
+
+            switch (options)
+            {
+                case MqttClientTcpOptions tcpOptions:
+                    return CreateTcpChannel(tcpOptions);
+                case MqttClientWebSocketOptions webSocketOptions:
+                    return CreateWebSocketChannel(webSocketOptions);
+                default:
+                    throw new NotSupportedException();
+            }
+        }
+
+        public MqttTcpChannel CreateTcpChannel(MqttClientTcpOptions tcpOptions)
+        {
+            return new MqttTcpChannel(tcpOptions);
+        }
+
+        public MqttWebSocketChannel CreateWebSocketChannel(MqttClientWebSocketOptions webSocketOptions)
+        {
+            return new MqttWebSocketChannel(webSocketOptions);
+        }
+
+        public MqttPacketSerializer CreateSerializer(MqttProtocolVersion protocolVersion)
+        {
+            return new MqttPacketSerializer
+            {
+                ProtocolVersion = protocolVersion
+            };
+        }
+
+        public MqttClientSession CreateClientSession(string clientId, MqttClientSessionsManager clientSessionsManager)
+        {
+            return new MqttClientSession(
+                clientId,
+                _serviceProvider.GetRequiredService<IOptions<MqttServerOptions>>(),
+                clientSessionsManager,
+                _serviceProvider.GetRequiredService<MqttClientSubscriptionsManager>(),
+                _serviceProvider.GetRequiredService<ILogger<MqttClientSession>>(),
+                _serviceProvider.GetRequiredService<ILogger<MqttClientPendingMessagesQueue>>(),
+                _serviceProvider.GetRequiredService<IMqttClientRetainedMessageManager>()
+                );
+        }
+
+        public IMqttClient CreateMqttClient()
+        {
+            return _serviceProvider.GetRequiredService<IMqttClient>();
+        }
+
+        public IManagedMqttClient CreateManagedMqttClient()
+        {
+            return _serviceProvider.GetRequiredService<IManagedMqttClient>();
+        }
+
+        public IMqttServer CreateMqttServer()
+        {
+            return _serviceProvider.GetRequiredService<IMqttServer>();
+        }
+
+        public IMqttServer CreateMqttServer(Action<MqttServerOptions> configure)
+        {
+            if (configure == null) throw new ArgumentNullException(nameof(configure));
+
+            var options = _serviceProvider.GetRequiredService<IOptions<MqttServerOptions>>();
+            configure(options.Value);
+
+            return _serviceProvider.GetRequiredService<IMqttServer>();
+        }
+    }
+}

Frameworks/MQTTnet.NetStandard/MqttServerFactory.cs

@@ -1,18 +0,0 @@
-using System;
-using System.Collections.Generic;
-using MQTTnet.Core.Adapter;
-using MQTTnet.Core.Server;
-using MQTTnet.Implementations;
-
-namespace MQTTnet
-{
-    public class MqttServerFactory : IMqttServerFactory
-    {
-        public IMqttServer CreateMqttServer(MqttServerOptions options)
-        {
-            if (options == null) throw new ArgumentNullException(nameof(options));
-
-            return new MqttServer(options, new List<IMqttServerAdapter> { new MqttServerAdapter() });
-        }
-    }
-}

Frameworks/MQTTnet.NetStandard/ServiceCollectionExtensions.cs

@@ -0,0 +1,70 @@
+using Microsoft.Extensions.DependencyInjection;
+using MQTTnet.Core.Adapter;
+using MQTTnet.Core.Client;
+using MQTTnet.Core.ManagedClient;
+using MQTTnet.Core.Serializer;
+using MQTTnet.Core.Server;
+using MQTTnet.Implementations;
+using System;
+using Microsoft.Extensions.Logging;
+using MQTTnet.Core.Diagnostics;
+
+namespace MQTTnet
+{
+    public static class ServiceCollectionExtensions
+    {
+        public static IServiceCollection AddMqttServer(this IServiceCollection services)
+        {
+            services.AddMqttServerServices();
+            
+            services.AddSingleton<IMqttServer>(s => s.GetService<MqttServer>());
+            services.AddSingleton<MqttServer>();
+
+            return services;
+        }
+
+        public static IServiceCollection AddMqttServerServices(this IServiceCollection services)
+        {
+            services.AddOptions();
+            services.AddSingleton<MqttFactory>();
+            services.AddSingleton<IMqttCommunicationAdapterFactory>(s => s.GetService<MqttFactory>());
+            services.AddSingleton<IMqttClientSesssionFactory>(s => s.GetService<MqttFactory>());
+
+            services.AddTransient<IMqttServerAdapter, MqttServerAdapter>();
+            services.AddTransient<IMqttPacketSerializer, MqttPacketSerializer>();
+
+            services.AddSingleton<MqttClientSessionsManager>();
+            services.AddTransient<MqttClientSubscriptionsManager>();
+            services.AddSingleton<IMqttClientRetainedMessageManager, MqttClientRetainedMessagesManager>();
+            return services;
+        }
+
+        public static IServiceCollection AddMqttServer(this IServiceCollection services, Action<MqttServerOptions> configureOptions)
+        {
+            return services
+                .AddMqttServer()
+                .Configure(configureOptions);
+        }
+
+        public static IServiceCollection AddMqttClient(this IServiceCollection services)
+        {
+            services.AddSingleton<MqttFactory>();
+            services.AddSingleton<IMqttCommunicationAdapterFactory>(s => s.GetService<MqttFactory>());
+
+            services.AddTransient<IMqttClient, MqttClient>();
+            services.AddTransient<MqttClient>();
+            services.AddTransient<IManagedMqttClient, ManagedMqttClient>();
+            services.AddTransient<ManagedMqttClient>();
+            services.AddTransient<IMqttPacketSerializer, MqttPacketSerializer>();
+            services.AddTransient<MqttPacketDispatcher>();
+
+            return services;
+        }
+
+        public static ILoggerFactory AddMqttTrace(this ILoggerFactory factory)
+        {
+            factory.AddProvider(new MqttNetTrace());
+            return factory;
+        }
+    }
+}

Frameworks/MQTTnet.UniversalWindows/Implementations/MqttServerAdapter.cs

@@ -1,65 +0,0 @@
-using System;
-using MQTTnet.Core.Adapter;
-using MQTTnet.Core.Diagnostics;
-using MQTTnet.Core.Serializer;
-using MQTTnet.Core.Server;
-using Windows.Networking.Sockets;
-
-namespace MQTTnet.Implementations
-{
-    public class MqttServerAdapter : IMqttServerAdapter, IDisposable
-    {
-        private StreamSocketListener _defaultEndpointSocket;
-
-        private bool _isRunning;
-
-        public event EventHandler<MqttClientConnectedEventArgs> ClientConnected;
-
-        public void Start(MqttServerOptions options)
-        {
-            if (options == null) throw new ArgumentNullException(nameof(options));
-
-            if (_isRunning) throw new InvalidOperationException("Server is already started.");
-
-            _isRunning = true;
-
-            if (options.DefaultEndpointOptions.IsEnabled)
-            {
-                _defaultEndpointSocket = new StreamSocketListener();
-                _defaultEndpointSocket.BindServiceNameAsync(options.GetDefaultEndpointPort().ToString(), SocketProtectionLevel.PlainSocket).GetAwaiter().GetResult();
-                _defaultEndpointSocket.ConnectionReceived += AcceptDefaultEndpointConnectionsAsync;
-            }
-
-            if (options.TlsEndpointOptions.IsEnabled)
-            {
-                throw new NotSupportedException("TLS servers are not supported for UWP apps.");
-            }
-        }
-
-        public void Stop()
-        {
-            _isRunning = false;
-
-            _defaultEndpointSocket?.Dispose();
-            _defaultEndpointSocket = null;
-        }
-
-        public void Dispose()
-        {
-            Stop();
-        }
-
-        private void AcceptDefaultEndpointConnectionsAsync(StreamSocketListener sender, StreamSocketListenerConnectionReceivedEventArgs args)
-        {
-            try
-            {
-                var clientAdapter = new MqttChannelCommunicationAdapter(new MqttTcpChannel(args.Socket), new MqttPacketSerializer());
-                ClientConnected?.Invoke(this, new MqttClientConnectedEventArgs(args.Socket.Information.RemoteAddress.ToString(), clientAdapter));
-            }
-            catch (Exception exception)
-            {
-                MqttTrace.Error(nameof(MqttServerAdapter), exception, "Error while accepting connection at default endpoint.");
-            }
-        }
-    }
-}

Frameworks/MQTTnet.UniversalWindows/Implementations/MqttTcpChannel.cs

@@ -1,98 +0,0 @@
-using System;
-using System.IO;
-using System.Linq;
-using System.Runtime.InteropServices.WindowsRuntime;
-using System.Threading.Tasks;
-using Windows.Networking;
-using Windows.Networking.Sockets;
-using Windows.Security.Cryptography.Certificates;
-using MQTTnet.Core.Channel;
-using MQTTnet.Core.Client;
-
-namespace MQTTnet.Implementations
-{
-    public sealed class MqttTcpChannel : IMqttCommunicationChannel, IDisposable
-    {
-        private StreamSocket _socket;
-
-        public MqttTcpChannel()
-        {
-        }
-
-        public MqttTcpChannel(StreamSocket socket)
-        {
-            _socket = socket ?? throw new ArgumentNullException(nameof(socket));
-        }
-
-        public Stream SendStream { get; private set; }
-        public Stream ReceiveStream { get; private set; }
-        public Stream RawReceiveStream { get; private set; }
-
-        public async Task ConnectAsync(MqttClientOptions options)
-        {
-            if (options == null) throw new ArgumentNullException(nameof(options));
-
-            if (_socket == null)
-            {
-                _socket = new StreamSocket();
-            }
-
-            if (!options.TlsOptions.UseTls)
-            {
-                await _socket.ConnectAsync(new HostName(options.Server), options.GetPort().ToString());
-            }
-            else
-            {
-                _socket.Control.ClientCertificate = LoadCertificate(options);
-
-                if (!options.TlsOptions.CheckCertificateRevocation)
-                {
-                    _socket.Control.IgnorableServerCertificateErrors.Add(ChainValidationResult.IncompleteChain);
-                    _socket.Control.IgnorableServerCertificateErrors.Add(ChainValidationResult.RevocationInformationMissing);
-                }
-
-                await _socket.ConnectAsync(new HostName(options.Server), options.GetPort().ToString(), SocketProtectionLevel.Tls12);
-            }
-
-            SendStream = _socket.OutputStream.AsStreamForWrite();
-            ReceiveStream = _socket.InputStream.AsStreamForRead();
-            RawReceiveStream = ReceiveStream;
-        }
-
-        public Task DisconnectAsync()
-        {
-            Dispose();
-            return Task.FromResult(0);
-        }
-
-        public void Dispose()
-        {
-            RawReceiveStream?.Dispose();
-            RawReceiveStream = null;
-
-            SendStream?.Dispose();
-            SendStream = null;
-
-            ReceiveStream?.Dispose();
-            ReceiveStream = null;
-
-            _socket?.Dispose();
-            _socket = null;
-        }
-
-        private static Certificate LoadCertificate(MqttClientOptions options)
-        {
-            if (options.TlsOptions.Certificates == null || !options.TlsOptions.Certificates.Any())
-            {
-                return null;
-            }
-
-            if (options.TlsOptions.Certificates.Count > 1)
-            {
-                throw new NotSupportedException("Only one client certificate is supported for UWP.");
-            }
-
-            return new Certificate(options.TlsOptions.Certificates.First().AsBuffer());
-        }
-    }
-}

Frameworks/MQTTnet.UniversalWindows/Implementations/MqttWebSocketChannel.cs

@@ -1,56 +0,0 @@
-using MQTTnet.Core.Channel;
-using MQTTnet.Core.Client;
-using System;
-using System.IO;
-using System.Net.WebSockets;
-using System.Threading;
-using System.Threading.Tasks;
-
-namespace MQTTnet.Implementations
-{
-    public sealed class MqttWebSocketChannel : IMqttCommunicationChannel, IDisposable
-    {
-        private ClientWebSocket _webSocket = new ClientWebSocket();
-
-        public Stream RawReceiveStream { get; private set; }
-        public Stream SendStream => RawReceiveStream;
-        public Stream ReceiveStream => RawReceiveStream;
-
-        public async Task ConnectAsync(MqttClientOptions options)
-        {
-            var uri = options.Server;
-            if (!uri.StartsWith("ws://", StringComparison.OrdinalIgnoreCase))
-            {
-                uri = "ws://" + uri;
-            }
-
-            if (options.Port.HasValue)
-            {
-                uri += ":" + options.Port;
-            }
-            
-            _webSocket = new ClientWebSocket();
-            _webSocket.Options.KeepAliveInterval = options.KeepAlivePeriod;
-            await _webSocket.ConnectAsync(new Uri(uri), CancellationToken.None).ConfigureAwait(false);
-
-            RawReceiveStream = new WebSocketStream(_webSocket);
-        }
-
-        public async Task DisconnectAsync()
-        {
-            RawReceiveStream = null;
-
-            if (_webSocket == null)
-            {
-                return;
-            }
-
-            await _webSocket.CloseAsync(WebSocketCloseStatus.NormalClosure, string.Empty, CancellationToken.None).ConfigureAwait(false);
-        }
-
-        public void Dispose()
-        {
-            _webSocket?.Dispose();
-        }
-    }
-}

Frameworks/MQTTnet.UniversalWindows/Implementations/WebSocketStream.cs

@@ -1,77 +0,0 @@
-using System;
-using System.IO;
-using System.Net.WebSockets;
-using System.Threading;
-using System.Threading.Tasks;
-
-namespace MQTTnet.Implementations
-{
-    public class WebSocketStream : Stream
-    {
-        private readonly ClientWebSocket _webSocket;
-
-        public WebSocketStream(ClientWebSocket webSocket)
-        {
-            _webSocket = webSocket;
-        }
-
-        public override void Flush()
-        {
-        }
-
-        public override async Task<int> ReadAsync(byte[] buffer, int offset, int count, CancellationToken cancellationToken)
-        {
-            var currentOffset = offset;
-            var targetOffset = offset + count;
-            while (_webSocket.State == WebSocketState.Open && currentOffset < targetOffset)
-            {
-                var response = await _webSocket.ReceiveAsync(new ArraySegment<byte>(buffer, currentOffset, count), cancellationToken).ConfigureAwait(false);
-                currentOffset += response.Count;
-                
-                if (response.MessageType == WebSocketMessageType.Close)
-                {
-                    await _webSocket.CloseAsync(WebSocketCloseStatus.NormalClosure, string.Empty, cancellationToken).ConfigureAwait(false);
-                }
-            }
-
-            return currentOffset - offset;
-        }
-
-        public override Task WriteAsync(byte[] buffer, int offset, int count, CancellationToken cancellationToken)
-        {
-            return _webSocket.SendAsync(new ArraySegment<byte>(buffer, offset, count), WebSocketMessageType.Binary, true, cancellationToken);
-        }
-
-        public override int Read(byte[] buffer, int offset, int count)
-        {
-            return ReadAsync(buffer, offset, count).GetAwaiter().GetResult();
-        }
-
-        public override void Write(byte[] buffer, int offset, int count)
-        {
-            WriteAsync(buffer, offset, count).GetAwaiter().GetResult();
-        }
-
-        public override bool CanRead => true;
-        public override bool CanSeek => false;
-        public override bool CanWrite => true;
-
-        public override long Length => throw new NotSupportedException();
-
-        public override long Position
-        {
-            get => throw new NotSupportedException();
-            set => throw new NotSupportedException();
-        }
-
-        public override long Seek(long offset, SeekOrigin origin)
-        {
-            throw new NotSupportedException();
-        }
-
-        public override void SetLength(long value)
-        {
-            throw new NotSupportedException();
-        }
-    }
-}

Frameworks/MQTTnet.UniversalWindows/MQTTnet.UniversalWindows.csproj

@@ -1,199 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<Project ToolsVersion="14.0" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
-  <Import Project="$(MSBuildExtensionsPath)\$(MSBuildToolsVersion)\Microsoft.Common.props" Condition="Exists('$(MSBuildExtensionsPath)\$(MSBuildToolsVersion)\Microsoft.Common.props')" />
-  <PropertyGroup>
-    <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
-    <Platform Condition=" '$(Platform)' == '' ">AnyCPU</Platform>
-    <ProjectGuid>{BD60C727-D8E8-40C3-B8E3-C95A864AE611}</ProjectGuid>
-    <OutputType>Library</OutputType>
-    <AppDesignerFolder>Properties</AppDesignerFolder>
-    <RootNamespace>MQTTnet</RootNamespace>
-    <AssemblyName>MQTTnet</AssemblyName>
-    <DefaultLanguage>en-US</DefaultLanguage>
-    <TargetPlatformIdentifier>UAP</TargetPlatformIdentifier>
-    <TargetPlatformVersion>10.0.15063.0</TargetPlatformVersion>
-    <TargetPlatformMinVersion>10.0.10240.0</TargetPlatformMinVersion>
-    <MinimumVisualStudioVersion>14</MinimumVisualStudioVersion>
-    <FileAlignment>512</FileAlignment>
-    <ProjectTypeGuids>{A5A43C5B-DE2A-4C0C-9213-0A381AF9435A};{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}</ProjectTypeGuids>
-    <RuntimeIdentifiers>win10-arm;win10-arm-aot;win10-x86;win10-x86-aot;win10-x64;win10-x64-aot</RuntimeIdentifiers>
-  </PropertyGroup>
-  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' ">
-    <PlatformTarget>AnyCPU</PlatformTarget>
-    <DebugSymbols>true</DebugSymbols>
-    <DebugType>full</DebugType>
-    <Optimize>false</Optimize>
-    <OutputPath>bin\Debug\</OutputPath>
-    <DefineConstants>DEBUG;TRACE;NETFX_CORE;WINDOWS_UWP</DefineConstants>
-    <ErrorReport>prompt</ErrorReport>
-    <WarningLevel>4</WarningLevel>
-    <NoWarn>CS1591</NoWarn>
-  </PropertyGroup>
-  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|AnyCPU' ">
-    <PlatformTarget>AnyCPU</PlatformTarget>
-    <DebugType>pdbonly</DebugType>
-    <Optimize>true</Optimize>
-    <OutputPath>bin\Release\</OutputPath>
-    <DefineConstants>TRACE;NETFX_CORE;WINDOWS_UWP</DefineConstants>
-    <ErrorReport>prompt</ErrorReport>
-    <WarningLevel>4</WarningLevel>
-    <NoWarn>CS1591</NoWarn>
-  </PropertyGroup>
-  <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Debug|x86'">
-    <PlatformTarget>x86</PlatformTarget>
-    <DebugSymbols>true</DebugSymbols>
-    <OutputPath>bin\x86\Debug\</OutputPath>
-    <DefineConstants>DEBUG;TRACE;NETFX_CORE;WINDOWS_UWP</DefineConstants>
-    <NoWarn>;2008,CS1591</NoWarn>
-    <DebugType>full</DebugType>
-    <PlatformTarget>x86</PlatformTarget>
-    <UseVSHostingProcess>false</UseVSHostingProcess>
-    <ErrorReport>prompt</ErrorReport>
-  </PropertyGroup>
-  <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Release|x86'">
-    <PlatformTarget>x86</PlatformTarget>
-    <OutputPath>bin\x86\Release\</OutputPath>
-    <DefineConstants>TRACE;NETFX_CORE;WINDOWS_UWP</DefineConstants>
-    <Optimize>true</Optimize>
-    <NoWarn>;2008,CS1591</NoWarn>
-    <DebugType>pdbonly</DebugType>
-    <PlatformTarget>x86</PlatformTarget>
-    <UseVSHostingProcess>false</UseVSHostingProcess>
-    <ErrorReport>prompt</ErrorReport>
-    <DocumentationFile>bin\x86\Release\MQTTnet.XML</DocumentationFile>
-  </PropertyGroup>
-  <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Debug|ARM'">
-    <PlatformTarget>ARM</PlatformTarget>
-    <DebugSymbols>true</DebugSymbols>
-    <OutputPath>bin\ARM\Debug\</OutputPath>
-    <DefineConstants>DEBUG;TRACE;NETFX_CORE;WINDOWS_UWP</DefineConstants>
-    <NoWarn>;2008,CS1591</NoWarn>
-    <DebugType>full</DebugType>
-    <PlatformTarget>ARM</PlatformTarget>
-    <UseVSHostingProcess>false</UseVSHostingProcess>
-    <ErrorReport>prompt</ErrorReport>
-  </PropertyGroup>
-  <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Release|ARM'">
-    <PlatformTarget>ARM</PlatformTarget>
-    <OutputPath>bin\ARM\Release\</OutputPath>
-    <DefineConstants>TRACE;NETFX_CORE;WINDOWS_UWP</DefineConstants>
-    <Optimize>true</Optimize>
-    <NoWarn>;2008,CS1591</NoWarn>
-    <DebugType>pdbonly</DebugType>
-    <PlatformTarget>ARM</PlatformTarget>
-    <UseVSHostingProcess>false</UseVSHostingProcess>
-    <ErrorReport>prompt</ErrorReport>
-    <DocumentationFile>bin\ARM\Release\MQTTnet.XML</DocumentationFile>
-  </PropertyGroup>
-  <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Debug|x64'">
-    <PlatformTarget>x64</PlatformTarget>
-    <DebugSymbols>true</DebugSymbols>
-    <OutputPath>bin\x64\Debug\</OutputPath>
-    <DefineConstants>DEBUG;TRACE;NETFX_CORE;WINDOWS_UWP</DefineConstants>
-    <NoWarn>;2008,CS1591</NoWarn>
-    <DebugType>full</DebugType>
-    <PlatformTarget>x64</PlatformTarget>
-    <UseVSHostingProcess>false</UseVSHostingProcess>
-    <ErrorReport>prompt</ErrorReport>
-  </PropertyGroup>
-  <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Release|x64'">
-    <PlatformTarget>x64</PlatformTarget>
-    <OutputPath>bin\x64\Release\</OutputPath>
-    <DefineConstants>TRACE;NETFX_CORE;WINDOWS_UWP</DefineConstants>
-    <Optimize>true</Optimize>
-    <NoWarn>;2008,CS1591</NoWarn>
-    <DebugType>pdbonly</DebugType>
-    <PlatformTarget>x64</PlatformTarget>
-    <UseVSHostingProcess>false</UseVSHostingProcess>
-    <ErrorReport>prompt</ErrorReport>
-    <GenerateLibraryLayout>false</GenerateLibraryLayout>
-    <DocumentationFile>bin\x64\Release\MQTTnet.XML</DocumentationFile>
-  </PropertyGroup>
-  <ItemGroup>
-    <Compile Include="Implementations\MqttWebSocketChannel.cs" />
-    <Compile Include="MqttClientFactory.cs" />
-    <Compile Include="Implementations\MqttServerAdapter.cs" />
-    <Compile Include="Implementations\MqttTcpChannel.cs" />
-    <Compile Include="MqttServerFactory.cs" />
-    <Compile Include="Properties\AssemblyInfo.cs" />
-    <Compile Include="Implementations\WebSocketStream.cs" />
-    <EmbeddedResource Include="Properties\MQTTnet.Universal.rd.xml" />
-  </ItemGroup>
-  <ItemGroup>
-    <ProjectReference Include="..\..\MQTTnet.Core\MQTTnet.Core.csproj">
-      <Project>{2ecb99e4-72d0-4c23-99ba-93d511d3967d}</Project>
-      <Name>MQTTnet.Core</Name>
-    </ProjectReference>
-  </ItemGroup>
-  <ItemGroup>
-    <PackageReference Include="Microsoft.NETCore.UniversalWindowsPlatform">
-      <Version>5.4.0</Version>
-    </PackageReference>
-  </ItemGroup>
-  <ItemGroup>
-    <Reference Include="System.Net.Security">
-      <HintPath>..\..\..\..\Program Files\dotnet\sdk\NuGetFallbackFolder\microsoft.netcore.app\2.0.0\ref\netcoreapp2.0\System.Net.Security.dll</HintPath>
-    </Reference>
-  </ItemGroup>
-  <PropertyGroup Condition=" '$(VisualStudioVersion)' == '' or '$(VisualStudioVersion)' &lt; '14.0' ">
-    <VisualStudioVersion>14.0</VisualStudioVersion>
-  </PropertyGroup>
-  <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Any CPU|AnyCPU'">
-    <OutputPath>bin\Any CPU\</OutputPath>
-    <DefineConstants>TRACE;NETFX_CORE;WINDOWS_UWP</DefineConstants>
-    <Optimize>true</Optimize>
-    <NoStdLib>true</NoStdLib>
-    <DebugType>pdbonly</DebugType>
-    <PlatformTarget>AnyCPU</PlatformTarget>
-    <UseVSHostingProcess>false</UseVSHostingProcess>
-    <ErrorReport>prompt</ErrorReport>
-    <CodeAnalysisRuleSet>MinimumRecommendedRules.ruleset</CodeAnalysisRuleSet>
-  </PropertyGroup>
-  <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Any CPU|x86'">
-    <OutputPath>bin\x86\Any CPU\</OutputPath>
-    <DefineConstants>TRACE;NETFX_CORE;WINDOWS_UWP</DefineConstants>
-    <DocumentationFile>bin\x86\Release\MQTTnet.XML</DocumentationFile>
-    <Optimize>true</Optimize>
-    <NoWarn>;2008</NoWarn>
-    <NoStdLib>true</NoStdLib>
-    <DebugType>pdbonly</DebugType>
-    <PlatformTarget>x86</PlatformTarget>
-    <UseVSHostingProcess>false</UseVSHostingProcess>
-    <ErrorReport>prompt</ErrorReport>
-    <CodeAnalysisRuleSet>MinimumRecommendedRules.ruleset</CodeAnalysisRuleSet>
-  </PropertyGroup>
-  <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Any CPU|ARM'">
-    <OutputPath>bin\ARM\Any CPU\</OutputPath>
-    <DefineConstants>TRACE;NETFX_CORE;WINDOWS_UWP</DefineConstants>
-    <DocumentationFile>bin\ARM\Release\MQTTnet.XML</DocumentationFile>
-    <Optimize>true</Optimize>
-    <NoWarn>;2008</NoWarn>
-    <NoStdLib>true</NoStdLib>
-    <DebugType>pdbonly</DebugType>
-    <PlatformTarget>ARM</PlatformTarget>
-    <UseVSHostingProcess>false</UseVSHostingProcess>
-    <ErrorReport>prompt</ErrorReport>
-    <CodeAnalysisRuleSet>MinimumRecommendedRules.ruleset</CodeAnalysisRuleSet>
-  </PropertyGroup>
-  <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Any CPU|x64'">
-    <OutputPath>bin\x64\Any CPU\</OutputPath>
-    <DefineConstants>TRACE;NETFX_CORE;WINDOWS_UWP</DefineConstants>
-    <DocumentationFile>bin\x64\Release\MQTTnet.XML</DocumentationFile>
-    <Optimize>true</Optimize>
-    <NoWarn>;2008</NoWarn>
-    <NoStdLib>true</NoStdLib>
-    <DebugType>pdbonly</DebugType>
-    <PlatformTarget>x64</PlatformTarget>
-    <UseVSHostingProcess>false</UseVSHostingProcess>
-    <ErrorReport>prompt</ErrorReport>
-    <CodeAnalysisRuleSet>MinimumRecommendedRules.ruleset</CodeAnalysisRuleSet>
-  </PropertyGroup>
-  <Import Project="$(MSBuildExtensionsPath)\Microsoft\WindowsXaml\v$(VisualStudioVersion)\Microsoft.Windows.UI.Xaml.CSharp.targets" />
-  <!-- To modify your build process, add your task inside one of the targets below and uncomment it. 
-       Other similar extension points exist, see Microsoft.Common.targets.
-  <Target Name="BeforeBuild">
-  </Target>
-  <Target Name="AfterBuild">
-  </Target>
-  -->
-</Project>

Frameworks/MQTTnet.UniversalWindows/MqttClientFactory.cs

@@ -1,33 +0,0 @@
-using System;
-using MQTTnet.Core.Adapter;
-using MQTTnet.Core.Channel;
-using MQTTnet.Core.Client;
-using MQTTnet.Core.Serializer;
-using MQTTnet.Implementations;
-
-namespace MQTTnet
-{
-    public class MqttClientFactory : IMqttClientFactory
-    {
-        public IMqttClient CreateMqttClient(MqttClientOptions options)
-        {
-            if (options == null) throw new ArgumentNullException(nameof(options));
-
-            return new MqttClient(options, new MqttChannelCommunicationAdapter(GetMqttCommunicationChannel(options), new MqttPacketSerializer()));
-        }
-
-        private static IMqttCommunicationChannel GetMqttCommunicationChannel(MqttClientOptions options)
-        {
-            switch (options.ConnectionType)
-            {
-                case MqttConnectionType.Tcp:
-                    return new MqttTcpChannel();
-                case MqttConnectionType.Ws:
-                    return new MqttWebSocketChannel();
-
-                default:
-                    throw new NotSupportedException();
-            }
-        }
-    }
-}

Frameworks/MQTTnet.UniversalWindows/MqttServerFactory.cs

@@ -1,18 +0,0 @@
-using System;
-using System.Collections.Generic;
-using MQTTnet.Core.Adapter;
-using MQTTnet.Core.Server;
-using MQTTnet.Implementations;
-
-namespace MQTTnet
-{
-    public class MqttServerFactory : IMqttServerFactory
-    {
-        public IMqttServer CreateMqttServer(MqttServerOptions options)
-        {
-            if (options == null) throw new ArgumentNullException(nameof(options));
-
-            return new MqttServer(options, new List<IMqttServerAdapter> { new MqttServerAdapter() });
-        }
-    }
-}

Frameworks/MQTTnet.UniversalWindows/Properties/AssemblyInfo.cs

@@ -1,14 +0,0 @@
-using System.Reflection;
-using System.Runtime.InteropServices;
-
-[assembly: AssemblyTitle("MQTTnet")]
-[assembly: AssemblyDescription("MQTTnet for Universal Windows")]
-[assembly: AssemblyConfiguration("")]
-[assembly: AssemblyCompany("Christian Kratky")]
-[assembly: AssemblyProduct("MQTTnet")]
-[assembly: AssemblyCopyright("Copyright © Christian Kratky 2016-2017")]
-[assembly: AssemblyTrademark("")]
-[assembly: AssemblyCulture("")]
-[assembly: ComVisible(false)]
-[assembly: AssemblyVersion("2.3.0.0")]
-[assembly: AssemblyFileVersion("2.3.0.0")]

Frameworks/MQTTnet.UniversalWindows/Properties/MQTTnet.Universal.rd.xml

@@ -1,5 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<Directives xmlns="http://schemas.microsoft.com/netfx/2013/01/metadata">
-  <Library Name="MQTTnet.Universal">
-  </Library>
-</Directives>

LICENSE

@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2017 Christian
+Copyright (c) 2017 Christian Kratky
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

MQTTnet.Core/Adapter/IMqttCommunicationAdapter.cs

@@ -2,7 +2,6 @@
 using System.Collections.Generic;
 using System.Threading;
 using System.Threading.Tasks;
-using MQTTnet.Core.Client;
 using MQTTnet.Core.Packets;
 using MQTTnet.Core.Serializer;
 
@@ -12,7 +11,7 @@ namespace MQTTnet.Core.Adapter
     {
         IMqttPacketSerializer PacketSerializer { get; }
 
-        Task ConnectAsync(TimeSpan timeout, MqttClientOptions options);
+        Task ConnectAsync(TimeSpan timeout);
 
         Task DisconnectAsync(TimeSpan timeout);
 

MQTTnet.Core/Adapter/IMqttCommunicationAdapterFactory.cs

@@ -0,0 +1,12 @@
+using MQTTnet.Core.Client;
+using MQTTnet.Core.Channel;
+
+namespace MQTTnet.Core.Adapter
+{
+    public interface IMqttCommunicationAdapterFactory
+    {
+        IMqttCommunicationAdapter CreateClientCommunicationAdapter(IMqttClientOptions options);
+
+        IMqttCommunicationAdapter CreateServerCommunicationAdapter(IMqttCommunicationChannel channel);
+    }
+}

MQTTnet.Core/Adapter/IMqttServerAdapter.cs

@@ -1,14 +1,14 @@
 using System;
+using System.Threading.Tasks;
 using MQTTnet.Core.Server;
 
 namespace MQTTnet.Core.Adapter
 {
     public interface IMqttServerAdapter
     {
-        event EventHandler<MqttClientConnectedEventArgs> ClientConnected;
+        event EventHandler<MqttServerAdapterClientAcceptedEventArgs> ClientAccepted;
 
-        void Start(MqttServerOptions options);
-
-        void Stop();
+        Task StartAsync(MqttServerOptions options);
+        Task StopAsync();
     }
 }

MQTTnet.Core/Adapter/MqttChannelCommunicationAdapter.cs

@@ -4,39 +4,43 @@ using System.IO;
 using System.Threading;
 using System.Threading.Tasks;
 using MQTTnet.Core.Channel;
-using MQTTnet.Core.Client;
-using MQTTnet.Core.Diagnostics;
 using MQTTnet.Core.Exceptions;
 using MQTTnet.Core.Internal;
 using MQTTnet.Core.Packets;
 using MQTTnet.Core.Serializer;
+using Microsoft.Extensions.Logging;
 
 namespace MQTTnet.Core.Adapter
 {
     public class MqttChannelCommunicationAdapter : IMqttCommunicationAdapter
     {
+        private readonly SemaphoreSlim _semaphore = new SemaphoreSlim(1, 1);
+        private readonly ILogger<MqttChannelCommunicationAdapter> _logger;
         private readonly IMqttCommunicationChannel _channel;
-
-        private Task _sendTask = Task.FromResult(0); // this task is used to prevent overlapping write
-
-        public MqttChannelCommunicationAdapter(IMqttCommunicationChannel channel, IMqttPacketSerializer serializer)
+        
+        public MqttChannelCommunicationAdapter(IMqttCommunicationChannel channel, IMqttPacketSerializer serializer, ILogger<MqttChannelCommunicationAdapter> logger)
         {
+            _logger = logger ?? throw new ArgumentNullException(nameof(logger));
             _channel = channel ?? throw new ArgumentNullException(nameof(channel));
             PacketSerializer = serializer ?? throw new ArgumentNullException(nameof(serializer));
         }
 
         public IMqttPacketSerializer PacketSerializer { get; }
 
-        public async Task ConnectAsync(TimeSpan timeout, MqttClientOptions options)
+        public async Task ConnectAsync(TimeSpan timeout)
         {
             try
             {
-                await _channel.ConnectAsync(options).TimeoutAfter(timeout).ConfigureAwait(false);
+                await _channel.ConnectAsync().TimeoutAfter(timeout).ConfigureAwait(false);
             }
             catch (TaskCanceledException)
             {
                 throw;
             }
+            catch (OperationCanceledException)
+            {
+                throw;
+            }
             catch (MqttCommunicationTimedOutException)
             {
                 throw;
@@ -61,6 +65,10 @@ namespace MQTTnet.Core.Adapter
             {
                 throw;
             }
+            catch (OperationCanceledException)
+            {
+                throw;
+            }
             catch (MqttCommunicationTimedOutException)
             {
                 throw;
@@ -79,18 +87,20 @@ namespace MQTTnet.Core.Adapter
         {
             try
             {
-                lock (_channel)
+                await _semaphore.WaitAsync(cancellationToken).ConfigureAwait(false);
+
+                foreach (var packet in packets)
                 {
-                    foreach (var packet in packets)
+                    if (packet == null)
                     {
-                        MqttTrace.Information(nameof(MqttChannelCommunicationAdapter), "TX >>> {0} [Timeout={1}]", packet, timeout);
-
-                        var writeBuffer = PacketSerializer.Serialize(packet);
-                        _sendTask = _sendTask.ContinueWith(p => _channel.SendStream.WriteAsync(writeBuffer, 0, writeBuffer.Length, cancellationToken).ConfigureAwait(false), cancellationToken);
+                        continue;
                     }
-                }
 
-                await _sendTask; // configure await false generates stackoverflow
+                    _logger.LogInformation("TX >>> {0} [Timeout={1}]", packet, timeout);
+
+                    var writeBuffer = PacketSerializer.Serialize(packet);
+                    await _channel.SendStream.WriteAsync(writeBuffer, 0, writeBuffer.Length, cancellationToken).ConfigureAwait(false);
+                }
 
                 if (timeout > TimeSpan.Zero)
                 {
@@ -105,6 +115,10 @@ namespace MQTTnet.Core.Adapter
             {
                 throw;
             }
+            catch (OperationCanceledException)
+            {
+                throw;
+            }
             catch (MqttCommunicationTimedOutException)
             {
                 throw;
@@ -117,23 +131,27 @@ namespace MQTTnet.Core.Adapter
             {
                 throw new MqttCommunicationException(exception);
             }
+            finally
+            {
+                _semaphore.Release();
+            }
         }
 
         public async Task<MqttBasePacket> ReceivePacketAsync(TimeSpan timeout, CancellationToken cancellationToken)
         {
+            ReceivedMqttPacket receivedMqttPacket = null;
             try
             {
-                ReceivedMqttPacket receivedMqttPacket;
                 if (timeout > TimeSpan.Zero)
                 {
-                    receivedMqttPacket = await ReceiveAsync(_channel.RawReceiveStream, cancellationToken).TimeoutAfter(timeout).ConfigureAwait(false);
+                    receivedMqttPacket = await ReceiveAsync(_channel.ReceiveStream, cancellationToken).TimeoutAfter(timeout).ConfigureAwait(false);
                 }
                 else
                 {
                     receivedMqttPacket = await ReceiveAsync(_channel.ReceiveStream, cancellationToken).ConfigureAwait(false);
                 }
 
-                if (cancellationToken.IsCancellationRequested)
+                if (receivedMqttPacket == null || cancellationToken.IsCancellationRequested)
                 {
                     throw new TaskCanceledException();
                 }
@@ -144,13 +162,17 @@ namespace MQTTnet.Core.Adapter
                     throw new MqttProtocolViolationException("Received malformed packet.");
                 }
 
-                MqttTrace.Information(nameof(MqttChannelCommunicationAdapter), "RX <<< {0}", packet);
+                _logger.LogInformation("RX <<< {0}", packet);
                 return packet;
             }
             catch (TaskCanceledException)
             {
                 throw;
             }
+            catch (OperationCanceledException)
+            {
+                throw;
+            }
             catch (MqttCommunicationTimedOutException)
             {
                 throw;
@@ -163,11 +185,19 @@ namespace MQTTnet.Core.Adapter
             {
                 throw new MqttCommunicationException(exception);
             }
+            finally
+            {
+                receivedMqttPacket?.Dispose();
+            }
         }
 
         private static async Task<ReceivedMqttPacket> ReceiveAsync(Stream stream, CancellationToken cancellationToken)
         {
             var header = MqttPacketReader.ReadHeaderFromSource(stream, cancellationToken);
+            if (header == null)
+            {
+                return null;
+            }
 
             if (header.BodyLength == 0)
             {
@@ -186,4 +216,4 @@ namespace MQTTnet.Core.Adapter
             return new ReceivedMqttPacket(header, new MemoryStream(body, 0, body.Length));
         }
     }
-}
+}

MQTTnet.Core/Adapter/MqttClientConnectedEventArgs.cs

@@ -1,17 +0,0 @@
-using System;
-
-namespace MQTTnet.Core.Adapter
-{
-    public class MqttClientConnectedEventArgs : EventArgs
-    {
-        public MqttClientConnectedEventArgs(string identifier, IMqttCommunicationAdapter clientAdapter)
-        {
-            Identifier = identifier ?? throw new ArgumentNullException(nameof(identifier));
-            ClientAdapter = clientAdapter ?? throw new ArgumentNullException(nameof(clientAdapter));
-        }
-
-        public string Identifier { get; }
-
-        public IMqttCommunicationAdapter ClientAdapter { get; }
-    }
-}

MQTTnet.Core/Adapter/MqttCommunicationAdapterExtensions.cs

@@ -9,6 +9,8 @@ namespace MQTTnet.Core.Adapter
     {
         public static Task SendPacketsAsync(this IMqttCommunicationAdapter adapter, TimeSpan timeout, CancellationToken cancellationToken, params MqttBasePacket[] packets)
         {
+            if (adapter == null) throw new ArgumentNullException(nameof(adapter));
+
             return adapter.SendPacketsAsync(timeout, cancellationToken, packets);
         }
     }

MQTTnet.Core/Adapter/MqttServerAdapterClientAcceptedEventArgs.cs

@@ -0,0 +1,17 @@
+using System;
+using System.Threading.Tasks;
+
+namespace MQTTnet.Core.Adapter
+{
+    public class MqttServerAdapterClientAcceptedEventArgs : EventArgs
+    {
+        public MqttServerAdapterClientAcceptedEventArgs(IMqttCommunicationAdapter client)
+        {
+            Client = client ?? throw new ArgumentNullException(nameof(client));
+        }
+
+        public IMqttCommunicationAdapter Client { get; }
+
+        public Task SessionTask { get; set; }
+    }
+}

MQTTnet.Core/Adapter/ReceivedMqttPacket.cs

@@ -4,7 +4,7 @@ using MQTTnet.Core.Packets;
 
 namespace MQTTnet.Core.Adapter
 {
-    public class ReceivedMqttPacket
+    public sealed class ReceivedMqttPacket : IDisposable
     {
         public ReceivedMqttPacket(MqttPacketHeader header, MemoryStream body)
         {
@@ -15,5 +15,10 @@ namespace MQTTnet.Core.Adapter
         public MqttPacketHeader Header { get; }
 
         public MemoryStream Body { get; }
+
+        public void Dispose()
+        {
+            Body?.Dispose();
+        }
     }
 }

MQTTnet.Core/ApplicationMessagePublisherExtensions.cs

@@ -0,0 +1,16 @@
+using System;
+using System.Threading.Tasks;
+
+namespace MQTTnet.Core
+{
+    public static class ApplicationMessagePublisherExtensions
+    {
+        public static Task PublishAsync(this IApplicationMessagePublisher client, params MqttApplicationMessage[] applicationMessages)
+        {
+            if (client == null) throw new ArgumentNullException(nameof(client));
+            if (applicationMessages == null) throw new ArgumentNullException(nameof(applicationMessages));
+
+            return client.PublishAsync(applicationMessages);
+        }
+    }
+}

MQTTnet.Core/Channel/IMqttCommunicationChannel.cs

@@ -1,5 +1,4 @@
 using System.Threading.Tasks;
-using MQTTnet.Core.Client;
 using System.IO;
 
 namespace MQTTnet.Core.Channel
@@ -8,9 +7,8 @@ namespace MQTTnet.Core.Channel
     {
         Stream SendStream { get; }
         Stream ReceiveStream { get; }
-        Stream RawReceiveStream { get; }
 
-        Task ConnectAsync(MqttClientOptions options);
+        Task ConnectAsync();
         Task DisconnectAsync();
     }
 }

MQTTnet.Core/Client/IMqttClient.cs

@@ -5,20 +5,17 @@ using MQTTnet.Core.Packets;
 
 namespace MQTTnet.Core.Client
 {
-    public interface IMqttClient
+    public interface IMqttClient : IApplicationMessageReceiver, IApplicationMessagePublisher
     {
         bool IsConnected { get; }
 
-        event EventHandler<MqttApplicationMessageReceivedEventArgs> ApplicationMessageReceived;
-        event EventHandler Connected;
-        event EventHandler Disconnected;
+        event EventHandler<MqttClientConnectedEventArgs> Connected;
+        event EventHandler<MqttClientDisconnectedEventArgs> Disconnected;
 
-        Task ConnectAsync(MqttApplicationMessage willApplicationMessage = null);
+        Task<MqttClientConnectResult> ConnectAsync(IMqttClientOptions options);
         Task DisconnectAsync();
 
         Task<IList<MqttSubscribeResult>> SubscribeAsync(IEnumerable<TopicFilter> topicFilters);
         Task UnsubscribeAsync(IEnumerable<string> topicFilters);
-
-        Task PublishAsync(IEnumerable<MqttApplicationMessage> applicationMessages);
     }
 }

MQTTnet.Core/Client/IMqttClientChannelOptions.cs

@@ -0,0 +1,7 @@
+namespace MQTTnet.Core.Client
+{
+    public interface IMqttClientChannelOptions
+    {
+        MqttClientTlsOptions TlsOptions { get; }
+    }
+}

MQTTnet.Core/Client/IMqttClientCredentials.cs

@@ -0,0 +1,8 @@
+namespace MQTTnet.Core.Client
+{
+    public interface IMqttClientCredentials
+    {
+        string Password { get; }
+        string Username { get; }
+    }
+}

MQTTnet.Core/Client/IMqttClientFactory.cs

@@ -1,7 +1,11 @@
-namespace MQTTnet.Core.Client
+using MQTTnet.Core.ManagedClient;
+
+namespace MQTTnet.Core.Client
 {
     public interface IMqttClientFactory
     {
-        IMqttClient CreateMqttClient(MqttClientOptions options);
+        IMqttClient CreateMqttClient();
+
+        IManagedMqttClient CreateManagedMqttClient();
     }
 }

MQTTnet.Core/Client/IMqttClientOptions.cs

@@ -0,0 +1,24 @@
+using System;
+using MQTTnet.Core.Serializer;
+
+namespace MQTTnet.Core.Client
+{
+    public interface IMqttClientOptions
+    {
+        string ClientId { get; }
+
+        /// <summary>
+        /// The LogId is used to create a scope to correlate logging. If no value is provided the ClientId is used instead 
+        /// </summary>
+        string LogId { get; }
+        IMqttClientCredentials Credentials { get; }
+        bool CleanSession { get; }
+        MqttApplicationMessage WillMessage { get; }
+        
+        TimeSpan CommunicationTimeout { get; }
+        TimeSpan KeepAlivePeriod { get; }
+        MqttProtocolVersion ProtocolVersion { get; }
+
+        IMqttClientChannelOptions ChannelOptions { get; }
+    }
+}

MQTTnet.Core/Client/MqttApplicationMessageReceivedEventArgs.cs

@@ -1,14 +0,0 @@
-using System;
-
-namespace MQTTnet.Core.Client
-{
-    public sealed class MqttApplicationMessageReceivedEventArgs : EventArgs
-    {
-        public MqttApplicationMessageReceivedEventArgs(MqttApplicationMessage applicationMessage)
-        {
-            ApplicationMessage = applicationMessage ?? throw new ArgumentNullException(nameof(applicationMessage));
-        }
-
-        public MqttApplicationMessage ApplicationMessage { get; }
-    }
-}

MQTTnet.Core/Client/MqttClient.cs

@@ -4,81 +4,79 @@ using System.Linq;
 using System.Threading;
 using System.Threading.Tasks;
 using MQTTnet.Core.Adapter;
-using MQTTnet.Core.Diagnostics;
 using MQTTnet.Core.Exceptions;
 using MQTTnet.Core.Internal;
 using MQTTnet.Core.Packets;
 using MQTTnet.Core.Protocol;
+using Microsoft.Extensions.Logging;
 
 namespace MQTTnet.Core.Client
 {
     public class MqttClient : IMqttClient
     {
         private readonly HashSet<ushort> _unacknowledgedPublishPackets = new HashSet<ushort>();
-        private readonly MqttPacketDispatcher _packetDispatcher = new MqttPacketDispatcher();
-        private readonly MqttClientOptions _options;
-        private readonly IMqttCommunicationAdapter _adapter;
+        private readonly MqttPacketDispatcher _packetDispatcher;
+        private readonly IMqttCommunicationAdapterFactory _communicationAdapterFactory;
+        private readonly ILogger<MqttClient> _logger;
 
+        private IMqttClientOptions _options;
+        private bool _isReceivingPackets;
         private int _latestPacketIdentifier;
         private CancellationTokenSource _cancellationTokenSource;
+        private IMqttCommunicationAdapter _adapter;
+        private IDisposable _scopeHandle;
 
-        public MqttClient(MqttClientOptions options, IMqttCommunicationAdapter adapter)
+        public MqttClient(IMqttCommunicationAdapterFactory communicationAdapterFactory, ILogger<MqttClient> logger, MqttPacketDispatcher packetDispatcher)
         {
-            _options = options ?? throw new ArgumentNullException(nameof(options));
-            _adapter = adapter ?? throw new ArgumentNullException(nameof(adapter));
-
-            _adapter.PacketSerializer.ProtocolVersion = options.ProtocolVersion;
+            _communicationAdapterFactory = communicationAdapterFactory ?? throw new ArgumentNullException(nameof(communicationAdapterFactory));
+            _logger = logger ?? throw new ArgumentNullException(nameof(logger));
+            _packetDispatcher = packetDispatcher ?? throw new ArgumentNullException(nameof(packetDispatcher));
         }
 
-        public event EventHandler Connected;
-        public event EventHandler Disconnected;
+        public event EventHandler<MqttClientConnectedEventArgs> Connected;
+        public event EventHandler<MqttClientDisconnectedEventArgs> Disconnected;
         public event EventHandler<MqttApplicationMessageReceivedEventArgs> ApplicationMessageReceived;
 
-        public bool IsConnected => _cancellationTokenSource != null && !_cancellationTokenSource.IsCancellationRequested;
+        public bool IsConnected { get; private set; }
 
-        public async Task ConnectAsync(MqttApplicationMessage willApplicationMessage = null)
+        public async Task<MqttClientConnectResult> ConnectAsync(IMqttClientOptions options)
         {
+            if (options == null) throw new ArgumentNullException(nameof(options));
+            if (options.ChannelOptions == null) throw new ArgumentException("ChannelOptions are not set.");
+
             ThrowIfConnected("It is not allowed to connect with a server after the connection is established.");
 
             try
             {
+                _options = options;
                 _cancellationTokenSource = new CancellationTokenSource();
                 _latestPacketIdentifier = 0;
                 _packetDispatcher.Reset();
 
-                MqttTrace.Verbose(nameof(MqttClient), "Trying to connect with server.");
-                await _adapter.ConnectAsync(_options.DefaultCommunicationTimeout, _options).ConfigureAwait(false);
-                MqttTrace.Verbose(nameof(MqttClient), "Connection with server established.");
+                _adapter = _communicationAdapterFactory.CreateClientCommunicationAdapter(options);
 
-                StartReceivePackets(_cancellationTokenSource.Token);
+                _scopeHandle = _logger.BeginScope(options.LogId ?? options.ClientId);
+                _logger.LogTrace("Trying to connect with server.");
+                await _adapter.ConnectAsync(_options.CommunicationTimeout).ConfigureAwait(false);
+                _logger.LogTrace("Connection with server established.");
 
-                var connectPacket = new MqttConnectPacket
-                {
-                    ClientId = _options.ClientId,
-                    Username = _options.UserName,
-                    Password = _options.Password,
-                    CleanSession = _options.CleanSession,
-                    KeepAlivePeriod = (ushort)_options.KeepAlivePeriod.TotalSeconds,
-                    WillMessage = willApplicationMessage
-                };
+                await SetupIncomingPacketProcessingAsync().ConfigureAwait(false);
+                var connectResponse = await AuthenticateAsync(options.WillMessage).ConfigureAwait(false);
 
-                var response = await SendAndReceiveAsync<MqttConnAckPacket>(connectPacket).ConfigureAwait(false);
-                if (response.ConnectReturnCode != MqttConnectReturnCode.ConnectionAccepted)
-                {
-                    throw new MqttConnectingFailedException(response.ConnectReturnCode);
-                }
-
-                MqttTrace.Verbose(nameof(MqttClient), "MQTT connection with server established.");
+                _logger.LogTrace("MQTT connection with server established.");
 
                 if (_options.KeepAlivePeriod != TimeSpan.Zero)
                 {
                     StartSendKeepAliveMessages(_cancellationTokenSource.Token);
                 }
 
-                Connected?.Invoke(this, EventArgs.Empty);
+                IsConnected = true;
+                Connected?.Invoke(this, new MqttClientConnectedEventArgs(connectResponse.IsSessionPresent));
+                return new MqttClientConnectResult(connectResponse.IsSessionPresent);
             }
-            catch (Exception)
+            catch (Exception exception)
             {
+                _logger.LogError(new EventId(), exception, "Error while connecting with server.");
                 await DisconnectInternalAsync().ConfigureAwait(false);
                 throw;
             }
@@ -98,6 +96,7 @@ namespace MQTTnet.Core.Client
             finally
             {
                 await DisconnectInternalAsync().ConfigureAwait(false);
+                _scopeHandle.Dispose();
             }
         }
 
@@ -150,40 +149,79 @@ namespace MQTTnet.Core.Client
                 switch (qosGroup.Key)
                 {
                     case MqttQualityOfServiceLevel.AtMostOnce:
-                        {
-                            // No packet identifier is used for QoS 0 [3.3.2.2 Packet Identifier]
-                            await _adapter.SendPacketsAsync(_options.DefaultCommunicationTimeout, _cancellationTokenSource.Token, qosPackets);
-                            break;
-                        }
+                    {
+                        // No packet identifier is used for QoS 0 [3.3.2.2 Packet Identifier]
+                        await _adapter.SendPacketsAsync(_options.CommunicationTimeout, _cancellationTokenSource.Token, qosPackets).ConfigureAwait(false);
+                        break;
+                    }
                     case MqttQualityOfServiceLevel.AtLeastOnce:
+                    {
+                        foreach (var publishPacket in qosPackets)
                         {
-                            foreach (var publishPacket in qosPackets)
-                            {
-                                publishPacket.PacketIdentifier = GetNewPacketIdentifier();
-                                await SendAndReceiveAsync<MqttPubAckPacket>(publishPacket);
-                            }
-
-                            break;
+                            publishPacket.PacketIdentifier = GetNewPacketIdentifier();
+                            await SendAndReceiveAsync<MqttPubAckPacket>(publishPacket).ConfigureAwait(false);
                         }
+
+                        break;
+                    }
                     case MqttQualityOfServiceLevel.ExactlyOnce:
+                    {
+                        foreach (var publishPacket in qosPackets)
                         {
-                            foreach (var publishPacket in qosPackets)
-                            {
-                                publishPacket.PacketIdentifier = GetNewPacketIdentifier();
-                                var pubRecPacket = await SendAndReceiveAsync<MqttPubRecPacket>(publishPacket).ConfigureAwait(false);
-                                await SendAndReceiveAsync<MqttPubCompPacket>(pubRecPacket.CreateResponse<MqttPubRelPacket>()).ConfigureAwait(false);
-                            }
+                            publishPacket.PacketIdentifier = GetNewPacketIdentifier();
+                            var pubRecPacket = await SendAndReceiveAsync<MqttPubRecPacket>(publishPacket).ConfigureAwait(false);
+                            await SendAndReceiveAsync<MqttPubCompPacket>(pubRecPacket.CreateResponse<MqttPubRelPacket>()).ConfigureAwait(false);
+                        }
 
-                            break;
-                        }
+                        break;
+                    }
                     default:
-                        {
-                            throw new InvalidOperationException();
-                        }
+                    {
+                        throw new InvalidOperationException();
+                    }
                 }
             }
         }
 
+        private async Task<MqttConnAckPacket> AuthenticateAsync(MqttApplicationMessage willApplicationMessage)
+        {
+            var connectPacket = new MqttConnectPacket
+            {
+                ClientId = _options.ClientId,
+                Username = _options.Credentials?.Username,
+                Password = _options.Credentials?.Password,
+                CleanSession = _options.CleanSession,
+                KeepAlivePeriod = (ushort) _options.KeepAlivePeriod.TotalSeconds,
+                WillMessage = willApplicationMessage
+            };
+
+            var response = await SendAndReceiveAsync<MqttConnAckPacket>(connectPacket).ConfigureAwait(false);
+            if (response.ConnectReturnCode != MqttConnectReturnCode.ConnectionAccepted)
+            {
+                throw new MqttConnectingFailedException(response.ConnectReturnCode);
+            }
+
+            return response;
+        }
+
+        private async Task SetupIncomingPacketProcessingAsync()
+        {
+            _isReceivingPackets = false;
+
+#pragma warning disable CS4014 // Because this call is not awaited, execution of the current method continues before the call is completed
+            Task.Factory.StartNew(
+                () => ReceivePackets(_cancellationTokenSource.Token),
+                _cancellationTokenSource.Token,
+                TaskCreationOptions.LongRunning,
+                TaskScheduler.Default).ConfigureAwait(false);
+#pragma warning restore CS4014 // Because this call is not awaited, execution of the current method continues before the call is completed
+
+            while (!_isReceivingPackets && _cancellationTokenSource != null && !_cancellationTokenSource.IsCancellationRequested)
+            {
+                await Task.Delay(TimeSpan.FromMilliseconds(100)).ConfigureAwait(false);
+            }
+        }
+
         private void ThrowIfNotConnected()
         {
             if (!IsConnected) throw new MqttCommunicationException("The client is not connected.");
@@ -196,6 +234,9 @@ namespace MQTTnet.Core.Client
 
         private async Task DisconnectInternalAsync()
         {
+            var clientWasConnected = IsConnected;
+            IsConnected = false;
+
             var cts = _cancellationTokenSource;
             if (cts == null || cts.IsCancellationRequested)
             {
@@ -208,16 +249,16 @@ namespace MQTTnet.Core.Client
 
             try
             {
-                await _adapter.DisconnectAsync(_options.DefaultCommunicationTimeout).ConfigureAwait(false);
-                MqttTrace.Information(nameof(MqttClient), "Disconnected from adapter.");
+                await _adapter.DisconnectAsync(_options.CommunicationTimeout).ConfigureAwait(false);
+                _logger.LogInformation("Disconnected from adapter.");
             }
             catch (Exception exception)
             {
-                MqttTrace.Warning(nameof(MqttClient), exception, "Error while disconnecting from adapter.");
+                _logger.LogWarning(new EventId(), exception, "Error while disconnecting from adapter.");
             }
             finally
             {
-                Disconnected?.Invoke(this, EventArgs.Empty);
+                Disconnected?.Invoke(this, new MqttClientDisconnectedEventArgs(clientWasConnected));
             }
         }
 
@@ -225,7 +266,7 @@ namespace MQTTnet.Core.Client
         {
             try
             {
-                MqttTrace.Information(nameof(MqttClient), "Received <<< {0}", packet);
+                _logger.LogInformation("Received <<< {0}", packet);
 
                 if (packet is MqttPingReqPacket)
                 {
@@ -255,7 +296,7 @@ namespace MQTTnet.Core.Client
             }
             catch (Exception exception)
             {
-                MqttTrace.Error(nameof(MqttClient), exception, "Unhandled exception while processing received packet.");
+                _logger.LogError(new EventId(), exception, "Unhandled exception while processing received packet.");
             }
         }
 
@@ -264,11 +305,11 @@ namespace MQTTnet.Core.Client
             try
             {
                 var applicationMessage = publishPacket.ToApplicationMessage();
-                ApplicationMessageReceived?.Invoke(this, new MqttApplicationMessageReceivedEventArgs(applicationMessage));
+                ApplicationMessageReceived?.Invoke(this, new MqttApplicationMessageReceivedEventArgs(_options.ClientId, applicationMessage));
             }
             catch (Exception exception)
             {
-                MqttTrace.Error(nameof(MqttClient), exception, "Unhandled exception while handling application message.");
+                _logger.LogError(new EventId(), exception, "Unhandled exception while handling application message.");
             }
         }
 
@@ -283,7 +324,7 @@ namespace MQTTnet.Core.Client
             if (publishPacket.QualityOfServiceLevel == MqttQualityOfServiceLevel.AtLeastOnce)
             {
                 FireApplicationMessageReceivedEvent(publishPacket);
-                await SendAsync(new MqttPubAckPacket { PacketIdentifier = publishPacket.PacketIdentifier });
+                await SendAsync(new MqttPubAckPacket {PacketIdentifier = publishPacket.PacketIdentifier});
                 return;
             }
 
@@ -296,7 +337,7 @@ namespace MQTTnet.Core.Client
                 }
 
                 FireApplicationMessageReceivedEvent(publishPacket);
-                await SendAsync(new MqttPubRecPacket { PacketIdentifier = publishPacket.PacketIdentifier });
+                await SendAsync(new MqttPubRecPacket {PacketIdentifier = publishPacket.PacketIdentifier});
                 return;
             }
 
@@ -315,24 +356,24 @@ namespace MQTTnet.Core.Client
 
         private Task SendAsync(MqttBasePacket packet)
         {
-            return _adapter.SendPacketsAsync(_options.DefaultCommunicationTimeout, _cancellationTokenSource.Token, packet);
+            return _adapter.SendPacketsAsync(_options.CommunicationTimeout, _cancellationTokenSource.Token, packet);
         }
 
         private async Task<TResponsePacket> SendAndReceiveAsync<TResponsePacket>(MqttBasePacket requestPacket) where TResponsePacket : MqttBasePacket
         {
-            var wait = _packetDispatcher.WaitForPacketAsync(requestPacket, typeof(TResponsePacket), _options.DefaultCommunicationTimeout);
-            await _adapter.SendPacketsAsync(_options.DefaultCommunicationTimeout, _cancellationTokenSource.Token, requestPacket).ConfigureAwait(false);
-            return (TResponsePacket)await wait.ConfigureAwait(false);
+            var packetAwaiter = _packetDispatcher.WaitForPacketAsync(requestPacket, typeof(TResponsePacket), _options.CommunicationTimeout);
+            await _adapter.SendPacketsAsync(_options.CommunicationTimeout, _cancellationTokenSource.Token, requestPacket).ConfigureAwait(false);
+            return (TResponsePacket) await packetAwaiter.ConfigureAwait(false);
         }
 
         private ushort GetNewPacketIdentifier()
         {
-            return (ushort)Interlocked.Increment(ref _latestPacketIdentifier);
+            return (ushort) Interlocked.Increment(ref _latestPacketIdentifier);
         }
 
         private async Task SendKeepAliveMessagesAsync(CancellationToken cancellationToken)
         {
-            MqttTrace.Information(nameof(MqttClient), "Start sending keep alive packets.");
+            _logger.LogInformation("Start sending keep alive packets.");
 
             try
             {
@@ -347,7 +388,7 @@ namespace MQTTnet.Core.Client
                     await SendAndReceiveAsync<MqttPingRespPacket>(new MqttPingReqPacket()).ConfigureAwait(false);
                 }
             }
-            catch (TaskCanceledException)
+            catch (OperationCanceledException)
             {
             }
             catch (MqttCommunicationException exception)
@@ -357,28 +398,30 @@ namespace MQTTnet.Core.Client
                     return;
                 }
 
-                MqttTrace.Warning(nameof(MqttClient), exception, "MQTT communication exception while sending/receiving keep alive packets.");
+                _logger.LogWarning(new EventId(), exception, "MQTT communication exception while sending/receiving keep alive packets.");
                 await DisconnectInternalAsync().ConfigureAwait(false);
             }
             catch (Exception exception)
             {
-                MqttTrace.Warning(nameof(MqttClient), exception, "Unhandled exception while sending/receiving keep alive packets.");
+                _logger.LogWarning(new EventId(), exception, "Unhandled exception while sending/receiving keep alive packets.");
                 await DisconnectInternalAsync().ConfigureAwait(false);
             }
             finally
             {
-                MqttTrace.Information(nameof(MqttClient), "Stopped sending keep alive packets.");
+                _logger.LogInformation("Stopped sending keep alive packets.");
             }
         }
 
         private async Task ReceivePackets(CancellationToken cancellationToken)
         {
-            MqttTrace.Information(nameof(MqttClient), "Start receiving packets.");
+            _logger.LogInformation("Start receiving packets.");
 
             try
             {
                 while (!cancellationToken.IsCancellationRequested)
                 {
+                    _isReceivingPackets = true;
+
                     var packet = await _adapter.ReceivePacketAsync(TimeSpan.Zero, cancellationToken).ConfigureAwait(false);
                     if (cancellationToken.IsCancellationRequested)
                     {
@@ -388,7 +431,7 @@ namespace MQTTnet.Core.Client
                     StartProcessReceivedPacket(packet, cancellationToken);
                 }
             }
-            catch (TaskCanceledException)
+            catch (OperationCanceledException)
             {
             }
             catch (MqttCommunicationException exception)
@@ -398,38 +441,32 @@ namespace MQTTnet.Core.Client
                     return;
                 }
 
-                MqttTrace.Warning(nameof(MqttClient), exception, "MQTT communication exception while receiving packets.");
+                _logger.LogWarning(new EventId(), exception, "MQTT communication exception while receiving packets.");
                 await DisconnectInternalAsync().ConfigureAwait(false);
             }
             catch (Exception exception)
             {
-                MqttTrace.Error(nameof(MqttClient), exception, "Unhandled exception while receiving packets.");
+                _logger.LogError(new EventId(), exception, "Unhandled exception while receiving packets.");
                 await DisconnectInternalAsync().ConfigureAwait(false);
             }
             finally
             {
-                MqttTrace.Information(nameof(MqttClient), "Stopped receiving packets.");
+                _logger.LogInformation(nameof(MqttClient), "Stopped receiving packets.");
             }
         }
 
         private void StartProcessReceivedPacket(MqttBasePacket packet, CancellationToken cancellationToken)
         {
 #pragma warning disable CS4014 // Because this call is not awaited, execution of the current method continues before the call is completed
-            Task.Run(async () => await ProcessReceivedPacketAsync(packet), cancellationToken).ConfigureAwait(false);
-#pragma warning restore CS4014 // Because this call is not awaited, execution of the current method continues before the call is completed
-        }
-
-        private void StartReceivePackets(CancellationToken cancellationToken)
-        {
-#pragma warning disable CS4014 // Because this call is not awaited, execution of the current method continues before the call is completed
-            Task.Run(async () => await ReceivePackets(cancellationToken), cancellationToken).ConfigureAwait(false); ;
+            Task.Run(() => ProcessReceivedPacketAsync(packet), cancellationToken).ConfigureAwait(false);
 #pragma warning restore CS4014 // Because this call is not awaited, execution of the current method continues before the call is completed
         }
 
         private void StartSendKeepAliveMessages(CancellationToken cancellationToken)
         {
 #pragma warning disable CS4014 // Because this call is not awaited, execution of the current method continues before the call is completed
-            Task.Run(async () => await SendKeepAliveMessagesAsync(cancellationToken), cancellationToken).ConfigureAwait(false);
+            Task.Factory.StartNew(() => SendKeepAliveMessagesAsync(cancellationToken), cancellationToken, TaskCreationOptions.LongRunning, TaskScheduler.Default)
+                .ConfigureAwait(false);
 #pragma warning restore CS4014 // Because this call is not awaited, execution of the current method continues before the call is completed
         }
     }

MQTTnet.Core/Client/MqttClientConnectResult.cs

@@ -0,0 +1,12 @@
+namespace MQTTnet.Core.Client
+{
+    public class MqttClientConnectResult
+    {
+        public MqttClientConnectResult(bool isSessionPresent)
+        {
+            IsSessionPresent = isSessionPresent;
+        }
+
+        public bool IsSessionPresent { get; }
+    }
+}

MQTTnet.Core/Client/MqttClientConnectedEventArgs.cs

@@ -0,0 +1,14 @@
+using System;
+
+namespace MQTTnet.Core.Client
+{
+    public class MqttClientConnectedEventArgs : EventArgs
+    {
+        public MqttClientConnectedEventArgs(bool isSessionPresent)
+        {
+            IsSessionPresent = isSessionPresent;
+        }
+
+        public bool IsSessionPresent { get; }
+    }
+}

MQTTnet.Core/Client/MqttClientCredentials.cs

@@ -0,0 +1,9 @@
+namespace MQTTnet.Core.Client
+{
+    public class MqttClientCredentials : IMqttClientCredentials
+    {
+        public string Username { get; set; }
+
+        public string Password { get; set; }
+    }
+}

MQTTnet.Core/Client/MqttClientDisconnectedEventArgs.cs

@@ -0,0 +1,14 @@
+using System;
+
+namespace MQTTnet.Core.Client
+{
+    public class MqttClientDisconnectedEventArgs : EventArgs
+    {
+        public MqttClientDisconnectedEventArgs(bool clientWasConnected)
+        {
+            ClientWasConnected = clientWasConnected;
+        }
+
+        public bool ClientWasConnected { get; }
+    }
+}

MQTTnet.Core/Client/MqttClientExtensions.cs

@@ -2,20 +2,11 @@
 using System.Collections.Generic;
 using System.Linq;
 using System.Threading.Tasks;
-using MQTTnet.Core.Packets;
 
 namespace MQTTnet.Core.Client
 {
     public static class MqttClientExtensions
     {
-        public static Task PublishAsync(this IMqttClient client, params MqttApplicationMessage[] applicationMessages)
-        {
-            if (client == null) throw new ArgumentNullException(nameof(client));
-            if (applicationMessages == null) throw new ArgumentNullException(nameof(applicationMessages));
-
-            return client.PublishAsync(applicationMessages);
-        }
-
         public static Task<IList<MqttSubscribeResult>> SubscribeAsync(this IMqttClient client, params TopicFilter[] topicFilters)
         {
             if (client == null) throw new ArgumentNullException(nameof(client));

MQTTnet.Core/Client/MqttClientOptions.cs

@@ -3,28 +3,25 @@ using MQTTnet.Core.Serializer;
 
 namespace MQTTnet.Core.Client
 {
-    public sealed class MqttClientOptions
+    public class MqttClientOptions : IMqttClientOptions
     {
-        public string Server { get; set; }
+        public MqttApplicationMessage WillMessage { get; set; }
 
-        public int? Port { get; set; }
+        public string ClientId { get; set; } = Guid.NewGuid().ToString("N");
 
-        public MqttClientTlsOptions TlsOptions { get; set; } = new MqttClientTlsOptions();
-
-        public string UserName { get; set; }
-
-        public string Password { get; set; }
-
-        public string ClientId { get; set; } = Guid.NewGuid().ToString().Replace("-", string.Empty);
+        /// <inheritdoc />
+        public string LogId { get; set; }
 
         public bool CleanSession { get; set; } = true;
 
+        public IMqttClientCredentials Credentials { get; set; } = new MqttClientCredentials();
+
         public TimeSpan KeepAlivePeriod { get; set; } = TimeSpan.FromSeconds(5);
 
-        public TimeSpan DefaultCommunicationTimeout { get; set; } = TimeSpan.FromSeconds(10);
+        public TimeSpan CommunicationTimeout { get; set; } = TimeSpan.FromSeconds(10);
 
         public MqttProtocolVersion ProtocolVersion { get; set; } = MqttProtocolVersion.V311;
 
-        public MqttConnectionType ConnectionType { get; set; } = MqttConnectionType.Tcp;
+        public IMqttClientChannelOptions ChannelOptions { get; set; }
     }
 }

MQTTnet.Core/Client/MqttClientOptionsBuilder.cs

@@ -0,0 +1,141 @@
+using System;
+using System.Linq;
+using MQTTnet.Core.Serializer;
+
+namespace MQTTnet.Core.Client
+{
+    public class MqttClientOptionsBuilder
+    {
+        private readonly MqttClientOptions _options = new MqttClientOptions();
+        private MqttClientTcpOptions _tcpOptions;
+        private MqttClientWebSocketOptions _webSocketOptions;
+
+        private MqttClientTlsOptions _tlsOptions;
+
+        public MqttClientOptionsBuilder WithLogId(string value)
+        {
+            _options.LogId = value;
+            return this;
+        }
+
+        public MqttClientOptionsBuilder WithProtocolVersion(MqttProtocolVersion value)
+        {
+            _options.ProtocolVersion = value;
+            return this;
+        }
+
+        public MqttClientOptionsBuilder WithCommunicationTimeout(TimeSpan value)
+        {
+            _options.CommunicationTimeout = value;
+            return this;
+        }
+
+        public MqttClientOptionsBuilder WithCleanSession(bool value = true)
+        {
+            _options.CleanSession = value;
+            return this;
+        }
+
+        public MqttClientOptionsBuilder WithKeepAlivePeriod(TimeSpan value)
+        {
+            _options.KeepAlivePeriod = value;
+            return this;
+        }
+
+        public MqttClientOptionsBuilder WithClientId(string value)
+        {
+            _options.ClientId = value;
+            return this;
+        }
+
+        public MqttClientOptionsBuilder WithWillMessage(MqttApplicationMessage value)
+        {
+            _options.WillMessage = value;
+            return this;
+        }
+
+        public MqttClientOptionsBuilder WithCredentials(string username, string password = null)
+        {
+            _options.Credentials = new MqttClientCredentials
+            {
+                Username = username,
+                Password = password
+            };
+
+            return this;
+        }
+
+        public MqttClientOptionsBuilder WithTcpServer(string server, int? port = null)
+        {
+            _tcpOptions = new MqttClientTcpOptions
+            {
+                Server = server,
+                Port = port
+            };
+
+            return this;
+        }
+
+        public MqttClientOptionsBuilder WithWebSocketServer(string uri)
+        {
+            _webSocketOptions = new MqttClientWebSocketOptions
+            {
+                Uri = uri
+            };
+
+            return this;
+        }
+
+        public MqttClientOptionsBuilder WithTls(
+            bool allowUntrustedCertificates = false,
+            bool ignoreCertificateChainErrors = false,
+            bool ignoreCertificateRevocationErrors = false,
+            params byte[][] certificates)
+        {
+            _tlsOptions = new MqttClientTlsOptions
+            {
+                UseTls = true,
+                AllowUntrustedCertificates = allowUntrustedCertificates,
+                IgnoreCertificateChainErrors = ignoreCertificateChainErrors,
+                IgnoreCertificateRevocationErrors = ignoreCertificateRevocationErrors,
+                Certificates = certificates.ToList()
+            };
+
+            return this;
+        }
+
+        public MqttClientOptionsBuilder WithTls()
+        {
+            _tlsOptions = new MqttClientTlsOptions
+            {
+                UseTls = true
+            };
+
+            return this;
+        }
+
+        public IMqttClientOptions Build()
+        {
+            if (_tlsOptions != null)
+            {
+                if (_tcpOptions == null && _webSocketOptions == null)
+                {
+                    throw new InvalidOperationException("A channel (TCP or WebSocket) must be set if TLS is configured.");
+                }
+
+                if (_tcpOptions != null)
+                {
+                    _options.ChannelOptions = _tcpOptions;
+                }
+                else
+                {
+                    _options.ChannelOptions = _webSocketOptions;
+                }
+            }
+
+            _options.ChannelOptions = (IMqttClientChannelOptions)_tcpOptions ?? _webSocketOptions;
+
+            return _options;
+        }
+    }
+}

MQTTnet.Core/Client/MqttClientTcpOptions.cs

@@ -0,0 +1,11 @@
+namespace MQTTnet.Core.Client
+{
+    public class MqttClientTcpOptions : IMqttClientChannelOptions
+    {
+        public string Server { get; set; }
+
+        public int? Port { get; set; }
+
+        public MqttClientTlsOptions TlsOptions { get; set; } = new MqttClientTlsOptions();
+    }
+}

MQTTnet.Core/Client/MqttClientTcpOptionsExtensions.cs

@@ -2,9 +2,9 @@
 
 namespace MQTTnet.Core.Client
 {
-    public static class MqttClientOptionsExtensions
+    public static class MqttClientTcpOptionsExtensions
     {
-        public static int GetPort(this MqttClientOptions options)
+        public static int GetPort(this MqttClientTcpOptions options)
         {
             if (options == null) throw new ArgumentNullException(nameof(options));
 

MQTTnet.Core/Client/MqttClientTlsOptions.cs

@@ -2,11 +2,15 @@
 
 namespace MQTTnet.Core.Client
 {
-    public sealed class MqttClientTlsOptions
+    public class MqttClientTlsOptions
     {
         public bool UseTls { get; set; }
 
-        public bool CheckCertificateRevocation { get; set; }
+        public bool IgnoreCertificateRevocationErrors { get; set; }
+
+        public bool IgnoreCertificateChainErrors { get; set; }
+
+        public bool AllowUntrustedCertificates { get; set; }
 
         public List<byte[]> Certificates { get; set; }
     }

MQTTnet.Core/Client/MqttClientWebSocketOptions.cs

@@ -0,0 +1,18 @@
+using System.Collections.Generic;
+using System.Net;
+
+namespace MQTTnet.Core.Client
+{
+    public class MqttClientWebSocketOptions : IMqttClientChannelOptions
+    {
+        public string Uri { get; set; }
+
+        public IDictionary<string, string> RequestHeaders { get; set; }
+
+        public ICollection<string> SubProtocols { get; set; }
+
+        public CookieContainer CookieContainer { get; set; }
+
+        public MqttClientTlsOptions TlsOptions { get; set; } = new MqttClientTlsOptions();
+    }
+}

MQTTnet.Core/Client/MqttConnectionType.cs

@@ -1,8 +0,0 @@
-namespace MQTTnet.Core.Client
-{
-    public enum MqttConnectionType
-    {
-        Tcp,
-        Ws
-    }
-}

MQTTnet.Core/Client/MqttPacketDispatcher.cs

@@ -1,10 +1,10 @@
 using System;
+using System.Collections.Concurrent;
 using System.Threading.Tasks;
-using MQTTnet.Core.Diagnostics;
 using MQTTnet.Core.Exceptions;
 using MQTTnet.Core.Internal;
 using MQTTnet.Core.Packets;
-using System.Collections.Concurrent;
+using Microsoft.Extensions.Logging;
 
 namespace MQTTnet.Core.Client
 {
@@ -12,6 +12,12 @@ namespace MQTTnet.Core.Client
     {
         private readonly ConcurrentDictionary<Type, TaskCompletionSource<MqttBasePacket>> _packetByResponseType = new ConcurrentDictionary<Type, TaskCompletionSource<MqttBasePacket>>();
         private readonly ConcurrentDictionary<Type, ConcurrentDictionary<ushort, TaskCompletionSource<MqttBasePacket>>> _packetByResponseTypeAndIdentifier = new ConcurrentDictionary<Type, ConcurrentDictionary<ushort, TaskCompletionSource<MqttBasePacket>>>();
+        private readonly ILogger<MqttPacketDispatcher> _logger;
+
+        public MqttPacketDispatcher(ILogger<MqttPacketDispatcher> logger)
+        {
+            _logger = logger ?? throw new ArgumentNullException(nameof(logger));
+        }
 
         public async Task<MqttBasePacket> WaitForPacketAsync(MqttBasePacket request, Type responseType, TimeSpan timeout)
         {
@@ -20,11 +26,11 @@ namespace MQTTnet.Core.Client
             var packetAwaiter = AddPacketAwaiter(request, responseType);
             try
             {
-                return await packetAwaiter.Task.TimeoutAfter(timeout);
+                return await packetAwaiter.Task.TimeoutAfter(timeout).ConfigureAwait(false);
             }
             catch (MqttCommunicationTimedOutException)
             {
-                MqttTrace.Warning(nameof(MqttPacketDispatcher), "Timeout while waiting for packet of type '{0}'.", responseType.Name);
+                _logger.LogWarning("Timeout while waiting for packet of type '{0}'.", responseType.Name);
                 throw;
             }
             finally
@@ -67,10 +73,11 @@ namespace MQTTnet.Core.Client
         private TaskCompletionSource<MqttBasePacket> AddPacketAwaiter(MqttBasePacket request, Type responseType)
         {
             var tcs = new TaskCompletionSource<MqttBasePacket>();
-            if (request is IMqttPacketWithIdentifier withIdent)
+
+            if (request is IMqttPacketWithIdentifier requestWithIdentifier)
             {
                 var byId = _packetByResponseTypeAndIdentifier.GetOrAdd(responseType, key => new ConcurrentDictionary<ushort, TaskCompletionSource<MqttBasePacket>>());
-                byId[withIdent.PacketIdentifier] = tcs;
+                byId[requestWithIdentifier.PacketIdentifier] = tcs;
             }
             else
             {
@@ -82,10 +89,10 @@ namespace MQTTnet.Core.Client
 
         private void RemovePacketAwaiter(MqttBasePacket request, Type responseType)
         {
-            if (request is IMqttPacketWithIdentifier withIdent)
+            if (request is IMqttPacketWithIdentifier requestWithIdentifier)
             {
                 var byId = _packetByResponseTypeAndIdentifier.GetOrAdd(responseType, key => new ConcurrentDictionary<ushort, TaskCompletionSource<MqttBasePacket>>());
-                byId.TryRemove(withIdent.PacketIdentifier, out var _);
+                byId.TryRemove(requestWithIdentifier.PacketIdentifier, out var _);
             }
             else
             {

MQTTnet.Core/Diagnostics/MqttNetLogger.cs

@@ -0,0 +1,53 @@
+using System;
+using Microsoft.Extensions.Logging;
+
+namespace MQTTnet.Core.Diagnostics
+{
+    public class MqttNetLogger : ILogger
+    {
+        private readonly string _categoryName;
+        private readonly MqttNetTrace _mqttNetTrace;
+
+        public MqttNetLogger(string categoryName, MqttNetTrace mqttNetTrace)
+        {
+            _categoryName = categoryName;
+            _mqttNetTrace = mqttNetTrace;
+        }
+
+        public void Log<TState>(LogLevel logLevel, EventId eventId, TState state, Exception exception, Func<TState, Exception, string> formatter)
+        {
+            if (formatter == null)
+            {
+                throw new ArgumentNullException(nameof(formatter));
+            }
+
+            if (!MqttNetTrace.HasListeners)
+            {
+                return;
+            }
+
+            var message = formatter(state, exception);
+            var traceMessage = new MqttNetTraceMessage(DateTime.Now, Environment.CurrentManagedThreadId, _categoryName, logLevel, message, exception);
+            _mqttNetTrace.Publish(traceMessage);
+        }
+
+        public bool IsEnabled(LogLevel logLevel)
+        {
+            return MqttNetTrace.HasListeners;
+        }
+
+        //not supported: async local requires netstandard1.3
+        //for implementation see https://github.com/aspnet/Logging/blob/dev/src/Microsoft.Extensions.Logging.Console/ConsoleLogScope.cs
+        public IDisposable BeginScope<TState>(TState state)
+        {
+            return new DisposableScope();
+        }
+
+        private class DisposableScope : IDisposable
+        {
+            public void Dispose()
+            {
+            }
+        }
+    }
+}

MQTTnet.Core/Diagnostics/MqttNetTrace.cs

@@ -0,0 +1,35 @@
+using System;
+using System.Collections.Concurrent;
+using Microsoft.Extensions.Logging;
+
+namespace MQTTnet.Core.Diagnostics
+{
+    public class MqttNetTrace : ILoggerProvider
+    {
+        private readonly ConcurrentDictionary<string, MqttNetLogger> _loggers = new ConcurrentDictionary<string, MqttNetLogger>();
+
+        public static event EventHandler<MqttNetTraceMessagePublishedEventArgs> TraceMessagePublished;
+
+        public static bool HasListeners => TraceMessagePublished != null;
+
+        public void Publish(MqttNetTraceMessage traceMessage)
+        {
+            TraceMessagePublished?.Invoke(this, new MqttNetTraceMessagePublishedEventArgs(traceMessage));
+        }
+
+        public void Dispose()
+        {
+            TraceMessagePublished = null;
+        }
+
+        public ILogger CreateLogger(string categoryName)
+        {
+            return _loggers.GetOrAdd(categoryName, CreateLoggerImplementation);
+        }
+
+        private MqttNetLogger CreateLoggerImplementation(string categoryName)
+        {
+            return new MqttNetLogger(categoryName, this);
+        }
+    }
+}

MQTTnet.Core/Diagnostics/MqttNetTraceMessagePublishedEventArgs.cs

@@ -0,0 +1,14 @@
+using System;
+
+namespace MQTTnet.Core.Diagnostics
+{
+    public sealed class MqttNetTraceMessagePublishedEventArgs : EventArgs
+    {
+        public MqttNetTraceMessagePublishedEventArgs(MqttNetTraceMessage traceMessage)
+        {
+            TraceMessage = traceMessage ?? throw new ArgumentNullException(nameof(traceMessage));
+        }
+
+        public MqttNetTraceMessage TraceMessage { get; }
+    }
+}

MQTTnet.Core/Diagnostics/MqttTrace.cs

@@ -1,63 +0,0 @@
-using System;
-
-namespace MQTTnet.Core.Diagnostics
-{
-    public static class MqttTrace
-    {
-        public static event EventHandler<MqttTraceMessagePublishedEventArgs> TraceMessagePublished;
-
-        public static void Verbose(string source, string message, params object[] parameters)
-        {
-            Publish(source, MqttTraceLevel.Verbose, null, message, parameters);
-        }
-
-        public static void Information(string source, string message, params object[] parameters)
-        {
-            Publish(source, MqttTraceLevel.Information, null, message, parameters);
-        }
-
-        public static void Warning(string source, string message, params object[] parameters)
-        {
-            Publish(source, MqttTraceLevel.Warning, null, message, parameters);
-        }
-
-        public static void Warning(string source, Exception exception, string message, params object[] parameters)
-        {
-            Publish(source, MqttTraceLevel.Warning, exception, message, parameters);
-        }
-
-        public static void Error(string source, string message, params object[] parameters)
-        {
-            Publish(source, MqttTraceLevel.Error, null, message, parameters);
-        }
-
-        public static void Error(string source, Exception exception, string message, params object[] parameters)
-        {
-            Publish(source, MqttTraceLevel.Error, exception, message, parameters);
-        }
-
-        private static void Publish(string source, MqttTraceLevel traceLevel, Exception exception, string message, params object[] parameters)
-        {
-            var handler = TraceMessagePublished;
-            if (handler == null)
-            {
-                return;
-            }
-
-            if (parameters?.Length > 0)
-            {
-                try
-                {
-                    message = string.Format(message, parameters);
-                }
-                catch (Exception formatException)
-                {
-                    Error(nameof(MqttTrace), formatException, "Error while tracing message: " + message);
-                    return;
-                }
-            }
-
-            handler.Invoke(null, new MqttTraceMessagePublishedEventArgs(Environment.CurrentManagedThreadId, source, traceLevel, message, exception));
-        }
-    }
-}

MQTTnet.Core/Diagnostics/MqttTraceLevel.cs

@@ -1,10 +0,0 @@
-namespace MQTTnet.Core.Diagnostics
-{
-    public enum MqttTraceLevel
-    {
-        Verbose,
-        Information,
-        Warning,
-        Error
-    }
-}

MQTTnet.Core/Diagnostics/MqttTraceMessage.cs

@@ -1,11 +1,13 @@
 using System;
+using Microsoft.Extensions.Logging;
 
 namespace MQTTnet.Core.Diagnostics
 {
-    public sealed class MqttTraceMessagePublishedEventArgs : EventArgs
+    public sealed class MqttNetTraceMessage
     {
-        public MqttTraceMessagePublishedEventArgs(int threadId, string source, MqttTraceLevel level, string message, Exception exception)
+        public MqttNetTraceMessage(DateTime timestamp, int threadId, string source, LogLevel level, string message, Exception exception)
         {
+            Timestamp = timestamp;
             ThreadId = threadId;
             Source = source;
             Level = level;
@@ -13,11 +15,13 @@ namespace MQTTnet.Core.Diagnostics
             Exception = exception;
         }
 
+        public DateTime Timestamp { get; }
+
         public int ThreadId { get; }
 
         public string Source { get; }
 
-        public MqttTraceLevel Level { get; }
+        public LogLevel Level { get; }
 
         public string Message { get; }
 

MQTTnet.Core/Exceptions/MqttCommunicationException.cs

@@ -17,10 +17,5 @@ namespace MQTTnet.Core.Exceptions
             : base(message)
         {
         }
-
-        public MqttCommunicationException(string message, Exception innerException)
-            : base(message, innerException)
-        {
-        }
     }
 }

MQTTnet.Core/IApplicationMessagePublisher.cs

@@ -0,0 +1,10 @@
+using System.Collections.Generic;
+using System.Threading.Tasks;
+
+namespace MQTTnet.Core
+{
+    public interface IApplicationMessagePublisher
+    {
+        Task PublishAsync(IEnumerable<MqttApplicationMessage> applicationMessages);
+    }
+}

MQTTnet.Core/IApplicationMessageReceiver.cs

@@ -0,0 +1,10 @@
+using System;
+using MQTTnet.Core.Client;
+
+namespace MQTTnet.Core
+{
+    public interface IApplicationMessageReceiver
+    {
+        event EventHandler<MqttApplicationMessageReceivedEventArgs> ApplicationMessageReceived;
+    }
+}

MQTTnet.Core/Internal/MqttApplicationMessageExtensions.cs

@@ -6,12 +6,13 @@ namespace MQTTnet.Core.Internal
     {
         public static MqttApplicationMessage ToApplicationMessage(this MqttPublishPacket publishPacket)
         {
-            return new MqttApplicationMessage(
-                publishPacket.Topic,
-                publishPacket.Payload,
-                publishPacket.QualityOfServiceLevel,
-                publishPacket.Retain
-            );
+            return new MqttApplicationMessage
+            { 
+                Topic = publishPacket.Topic,
+                Payload = publishPacket.Payload,
+                QualityOfServiceLevel = publishPacket.QualityOfServiceLevel,
+                Retain = publishPacket.Retain
+            };
         }
 
         public static MqttPublishPacket ToPublishPacket(this MqttApplicationMessage applicationMessage)

MQTTnet.Core/MQTTnet.Core.csproj

@@ -17,19 +17,15 @@
     <PackageIconUrl></PackageIconUrl>
     <RepositoryUrl></RepositoryUrl>
     <PackageTags></PackageTags>
-    <FileVersion>2.3.0.0</FileVersion>
-    <AssemblyVersion>2.3.0.0</AssemblyVersion>
+    <FileVersion>2.5.0.0</FileVersion>
+    <AssemblyVersion>2.5.0.0</AssemblyVersion>
     <PackageLicenseUrl></PackageLicenseUrl>
   </PropertyGroup>
 
-  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Any CPU|AnyCPU'" />
-
-  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Any CPU|x64'" />
-
-  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|x86'" />
-
-  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|x86'" />
-
-  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Any CPU|x86'" />
+  <ItemGroup>
+    <PackageReference Include="Microsoft.Extensions.Logging.Abstractions" Version="1.1.2" />
+    <PackageReference Include="Microsoft.Extensions.Options" Version="1.1.2" />
+    <PackageReference Include="System.Threading" Version="4.3.0" />
+  </ItemGroup>
 
 </Project>

MQTTnet.Core/ManagedClient/IManagedMqttClient.cs

@@ -0,0 +1,21 @@
+using System;
+using System.Collections.Generic;
+using System.Threading.Tasks;
+using MQTTnet.Core.Client;
+
+namespace MQTTnet.Core.ManagedClient
+{
+    public interface IManagedMqttClient : IApplicationMessageReceiver, IApplicationMessagePublisher
+    {
+        bool IsConnected { get; }
+
+        event EventHandler<MqttClientConnectedEventArgs> Connected;
+        event EventHandler<MqttClientDisconnectedEventArgs> Disconnected;
+
+        Task StartAsync(IManagedMqttClientOptions options);
+        Task StopAsync();
+
+        Task SubscribeAsync(IEnumerable<TopicFilter> topicFilters);
+        Task UnsubscribeAsync(IEnumerable<TopicFilter> topicFilters);
+    }
+}

MQTTnet.Core/ManagedClient/IManagedMqttClientOptions.cs

@@ -0,0 +1,14 @@
+using System;
+using MQTTnet.Core.Client;
+
+namespace MQTTnet.Core.ManagedClient
+{
+    public interface IManagedMqttClientOptions
+    {
+        IMqttClientOptions ClientOptions { get; }
+
+        TimeSpan AutoReconnectDelay { get; }
+
+        IManagedMqttClientStorage Storage { get; }
+    }
+}

MQTTnet.Core/ManagedClient/IManagedMqttClientStorage.cs

@@ -0,0 +1,12 @@
+using System.Collections.Generic;
+using System.Threading.Tasks;
+
+namespace MQTTnet.Core.ManagedClient
+{
+    public interface IManagedMqttClientStorage
+    {
+        Task SaveQueuedMessagesAsync(IList<MqttApplicationMessage> messages);
+
+        Task<IList<MqttApplicationMessage>> LoadQueuedMessagesAsync();
+    }
+}

MQTTnet.Core/ManagedClient/ManagedMqttClient.cs

@@ -0,0 +1,303 @@
+using System;
+using System.Collections.Concurrent;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading;
+using System.Threading.Tasks;
+using MQTTnet.Core.Client;
+using MQTTnet.Core.Exceptions;
+using MQTTnet.Core.Protocol;
+using Microsoft.Extensions.Logging;
+
+namespace MQTTnet.Core.ManagedClient
+{
+    public class ManagedMqttClient : IManagedMqttClient
+    {
+        private readonly ManagedMqttClientStorageManager _storageManager = new ManagedMqttClientStorageManager();
+        private readonly BlockingCollection<MqttApplicationMessage> _messageQueue = new BlockingCollection<MqttApplicationMessage>();
+        private readonly HashSet<TopicFilter> _subscriptions = new HashSet<TopicFilter>();
+
+        private readonly IMqttClient _mqttClient;
+        private readonly ILogger<ManagedMqttClient> _logger;
+
+        private CancellationTokenSource _connectionCancellationToken;
+        private CancellationTokenSource _publishingCancellationToken;
+
+        private IManagedMqttClientOptions _options;
+        private bool _subscriptionsNotPushed;
+        
+        public ManagedMqttClient(ILogger<ManagedMqttClient> logger, IMqttClient mqttClient)
+        {
+            _logger = logger ?? throw new ArgumentNullException(nameof(logger));
+            _mqttClient = mqttClient ?? throw new ArgumentNullException(nameof(mqttClient));
+
+            _mqttClient.Connected += OnConnected;
+            _mqttClient.Disconnected += OnDisconnected;
+            _mqttClient.ApplicationMessageReceived += OnApplicationMessageReceived;
+        }
+
+        public bool IsConnected => _mqttClient.IsConnected;
+
+        public event EventHandler<MqttClientConnectedEventArgs> Connected;
+        public event EventHandler<MqttClientDisconnectedEventArgs> Disconnected;
+        public event EventHandler<MqttApplicationMessageReceivedEventArgs> ApplicationMessageReceived;
+
+        public async Task StartAsync(IManagedMqttClientOptions options)
+        {
+            if (options == null) throw new ArgumentNullException(nameof(options));
+            if (options.ClientOptions == null) throw new ArgumentException("The client options are not set.", nameof(options));
+
+            if (!options.ClientOptions.CleanSession)
+            {
+                throw new NotSupportedException("The managed client does not support existing sessions.");
+            }
+
+            if (_connectionCancellationToken != null)
+            {
+                throw new InvalidOperationException("The managed client is already started.");
+            }
+
+            _options = options;
+            await _storageManager.SetStorageAsync(_options.Storage).ConfigureAwait(false);
+
+            if (_options.Storage != null)
+            {
+                var loadedMessages = await _options.Storage.LoadQueuedMessagesAsync().ConfigureAwait(false);
+                foreach (var loadedMessage in loadedMessages)
+                {
+                    _messageQueue.Add(loadedMessage);    
+                }
+            }
+
+            _connectionCancellationToken = new CancellationTokenSource();
+            
+#pragma warning disable CS4014 // Because this call is not awaited, execution of the current method continues before the call is completed
+            Task.Factory.StartNew(() => MaintainConnectionAsync(_connectionCancellationToken.Token), _connectionCancellationToken.Token, TaskCreationOptions.LongRunning, TaskScheduler.Default).ConfigureAwait(false);
+#pragma warning restore CS4014 // Because this call is not awaited, execution of the current method continues before the call is completed
+
+            _logger.LogInformation("Started");
+        }
+
+        public Task StopAsync()
+        {
+            _connectionCancellationToken?.Cancel(false);
+            _connectionCancellationToken = null;
+
+            while (_messageQueue.Any())
+            {
+                _messageQueue.Take();
+            }
+
+            return Task.FromResult(0);
+        }
+
+        public async Task PublishAsync(IEnumerable<MqttApplicationMessage> applicationMessages)
+        {
+            if (applicationMessages == null) throw new ArgumentNullException(nameof(applicationMessages));
+
+            foreach (var applicationMessage in applicationMessages)
+            {
+                await _storageManager.AddAsync(applicationMessage).ConfigureAwait(false);
+                _messageQueue.Add(applicationMessage);
+            }
+        }
+
+        public Task SubscribeAsync(IEnumerable<TopicFilter> topicFilters)
+        {
+            if (topicFilters == null) throw new ArgumentNullException(nameof(topicFilters));
+
+            lock (_subscriptions)
+            {
+                foreach (var topicFilter in topicFilters)
+                {
+                    if (_subscriptions.Add(topicFilter))
+                    {
+                        _subscriptionsNotPushed = true;
+                    }
+                }
+            }
+
+            return Task.FromResult(0);
+        }
+
+        public Task UnsubscribeAsync(IEnumerable<TopicFilter> topicFilters)
+        {
+            lock (_subscriptions)
+            {
+                foreach (var topicFilter in topicFilters)
+                {
+                    if (_subscriptions.Remove(topicFilter))
+                    {
+                        _subscriptionsNotPushed = true;
+                    }
+                }
+            }
+
+            return Task.FromResult(0);
+        }
+
+        private async Task MaintainConnectionAsync(CancellationToken cancellationToken)
+        {
+            try
+            {
+                while (!cancellationToken.IsCancellationRequested)
+                {
+                    var connectionState = await ReconnectIfRequiredAsync().ConfigureAwait(false);
+                    if (connectionState == ReconnectionResult.NotConnected)
+                    {
+                        _publishingCancellationToken?.Cancel(false);
+                        _publishingCancellationToken = null;
+
+                        await Task.Delay(_options.AutoReconnectDelay, cancellationToken).ConfigureAwait(false);
+                        continue;
+                    }
+
+                    if (connectionState == ReconnectionResult.Reconnected || _subscriptionsNotPushed)
+                    {
+                        await PushSubscriptionsAsync();
+
+                        _publishingCancellationToken = new CancellationTokenSource();
+
+#pragma warning disable CS4014 // Because this call is not awaited, execution of the current method continues before the call is completed
+                        Task.Factory.StartNew(() => PublishQueuedMessagesAsync(_publishingCancellationToken.Token), _publishingCancellationToken.Token, TaskCreationOptions.LongRunning, TaskScheduler.Default).ConfigureAwait(false);
+#pragma warning restore CS4014 // Because this call is not awaited, execution of the current method continues before the call is completed
+
+                        continue;
+                    }
+
+                    if (connectionState == ReconnectionResult.StillConnected)
+                    {
+                        await Task.Delay(100, _connectionCancellationToken.Token).ConfigureAwait(false); // Consider using the _Disconnected_ event here. (TaskCompletionSource)
+                    }
+                }
+            }
+            catch (OperationCanceledException)
+            {
+            }
+            catch (MqttCommunicationException exception)
+            {
+                _logger.LogWarning(new EventId(), exception, "Communication exception while maintaining connection.");
+            }
+            catch (Exception exception)
+            {
+                _logger.LogError(new EventId(), exception, "Unhandled exception while maintaining connection.");
+            }
+            finally
+            {
+                await _mqttClient.DisconnectAsync().ConfigureAwait(false);
+                _logger.LogInformation("Stopped");
+            }
+        }
+
+        private async Task PublishQueuedMessagesAsync(CancellationToken cancellationToken)
+        {
+            try
+            {
+                while (!cancellationToken.IsCancellationRequested)
+                {
+                    var message = _messageQueue.Take(cancellationToken);
+                    if (message == null)
+                    {
+                        continue;
+                    }
+
+                    if (cancellationToken.IsCancellationRequested)
+                    {
+                        continue;
+                    }
+
+                    await TryPublishQueuedMessageAsync(message).ConfigureAwait(false);
+                    await _storageManager.RemoveAsync(message).ConfigureAwait(false);
+                }
+            }
+            catch (OperationCanceledException)
+            {
+            }
+            finally
+            {
+                _logger.LogInformation("Stopped publishing messages");
+            }
+        }
+
+        private async Task TryPublishQueuedMessageAsync(MqttApplicationMessage message)
+        {
+            try
+            {
+                await _mqttClient.PublishAsync(message).ConfigureAwait(false);
+            }
+            catch (MqttCommunicationException exception)
+            {
+                _logger.LogWarning(new EventId(), exception, "Publishing application message failed.");
+
+                if (message.QualityOfServiceLevel > MqttQualityOfServiceLevel.AtMostOnce)
+                {
+                    _messageQueue.Add(message);
+                }
+            }
+            catch (Exception exception)
+            {
+                _logger.LogError(new EventId(), exception, "Unhandled exception while publishing queued application message.");
+            }
+        }
+
+        private async Task PushSubscriptionsAsync()
+        {
+            _logger.LogInformation(nameof(ManagedMqttClient), "Synchronizing subscriptions");
+
+            List<TopicFilter> subscriptions;
+            lock (_subscriptions)
+            {
+                subscriptions = _subscriptions.ToList();
+                _subscriptionsNotPushed = false;
+            }
+
+            if (!_subscriptions.Any())
+            {
+                return;
+            }
+
+            try
+            {
+                await _mqttClient.SubscribeAsync(subscriptions).ConfigureAwait(false);
+            }
+            catch (Exception exception)
+            {
+                _logger.LogWarning(new EventId(), exception, "Synchronizing subscriptions failed");
+                _subscriptionsNotPushed = true;
+            }
+        }
+
+        private async Task<ReconnectionResult> ReconnectIfRequiredAsync()
+        {
+            if (_mqttClient.IsConnected)
+            {
+                return ReconnectionResult.StillConnected;
+            }
+
+            try
+            {
+                await _mqttClient.ConnectAsync(_options.ClientOptions).ConfigureAwait(false);
+                return ReconnectionResult.Reconnected;
+            }
+            catch (Exception)
+            {
+                return ReconnectionResult.NotConnected;
+            }
+        }
+
+        private void OnApplicationMessageReceived(object sender, MqttApplicationMessageReceivedEventArgs eventArgs)
+        {
+            ApplicationMessageReceived?.Invoke(this, eventArgs);
+        }
+
+        private void OnDisconnected(object sender, MqttClientDisconnectedEventArgs eventArgs)
+        {
+            Disconnected?.Invoke(this, eventArgs);
+        }
+
+        private void OnConnected(object sender, MqttClientConnectedEventArgs eventArgs)
+        {
+            Connected?.Invoke(this, eventArgs);
+        }
+    }
+}

MQTTnet.Core/ManagedClient/ManagedMqttClientExtensions.cs

@@ -0,0 +1,22 @@
+using System;
+using System.Threading.Tasks;
+
+namespace MQTTnet.Core.ManagedClient
+{
+    public static class ManagedMqttClientExtensions
+    {
+        public static Task SubscribeAsync(this IManagedMqttClient managedClient, params TopicFilter[] topicFilters)
+        {
+            if (managedClient == null) throw new ArgumentNullException(nameof(managedClient));
+
+            return managedClient.SubscribeAsync(topicFilters);
+        }
+
+        public static Task UnsubscribeAsync(this IManagedMqttClient managedClient, params TopicFilter[] topicFilters)
+        {
+            if (managedClient == null) throw new ArgumentNullException(nameof(managedClient));
+
+            return managedClient.UnsubscribeAsync(topicFilters);
+        }
+    }
+}

MQTTnet.Core/ManagedClient/ManagedMqttClientOptions.cs

@@ -0,0 +1,14 @@
+using System;
+using MQTTnet.Core.Client;
+
+namespace MQTTnet.Core.ManagedClient
+{
+    public class ManagedMqttClientOptions : IManagedMqttClientOptions
+    {
+        public IMqttClientOptions ClientOptions { get; set; }
+
+        public TimeSpan AutoReconnectDelay { get; set; } = TimeSpan.FromSeconds(5);
+
+        public IManagedMqttClientStorage Storage { get; set; }
+    }
+}

MQTTnet.Core/ManagedClient/ManagedMqttClientOptionsBuilder.cs

@@ -0,0 +1,49 @@
+using System;
+using MQTTnet.Core.Client;
+
+namespace MQTTnet.Core.ManagedClient
+{
+    public class ManagedMqttClientOptionsBuilder
+    {
+        private readonly ManagedMqttClientOptions _options = new ManagedMqttClientOptions();
+
+        public ManagedMqttClientOptionsBuilder WithAutoReconnectDelay(TimeSpan value)
+        {
+            _options.AutoReconnectDelay = value;
+            return this;
+        }
+
+        public ManagedMqttClientOptionsBuilder WithStorage(IManagedMqttClientStorage value)
+        {
+            _options.Storage = value;
+            return this;
+        }
+
+        public ManagedMqttClientOptionsBuilder WithClientOptions(IMqttClientOptions value)
+        {
+            _options.ClientOptions = value ?? throw new ArgumentNullException(nameof(value));
+            return this;
+        }
+
+        public ManagedMqttClientOptionsBuilder WithClientOptions(Action<MqttClientOptionsBuilder> options)
+        {
+            if (options == null) throw new ArgumentNullException(nameof(options));
+
+            var builder = new MqttClientOptionsBuilder();
+            options(builder);
+            _options.ClientOptions = builder.Build();
+
+            return this;
+        }
+
+        public ManagedMqttClientOptions Build()
+        {
+            if (_options.ClientOptions == null)
+            {
+                throw new InvalidOperationException("The ClientOptions cannot be null.");
+            }
+
+            return _options;
+        }
+    }
+}

MQTTnet.Core/ManagedClient/ManagedMqttClientStorageManager.cs

@@ -0,0 +1,75 @@
+using System.Collections.Generic;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace MQTTnet.Core.ManagedClient
+{
+    public class ManagedMqttClientStorageManager
+    {
+        private readonly List<MqttApplicationMessage> _applicationMessages = new List<MqttApplicationMessage>();
+        private readonly SemaphoreSlim _semaphore = new SemaphoreSlim(1, 1);
+        private IManagedMqttClientStorage _storage;
+
+        public async Task SetStorageAsync(IManagedMqttClientStorage storage)
+        {
+            await _semaphore.WaitAsync().ConfigureAwait(false);
+            try
+            {
+                _storage = storage;
+            }
+            finally
+            {
+                _semaphore.Release();
+            }
+        }
+
+        public async Task AddAsync(MqttApplicationMessage applicationMessage)
+        {
+            await _semaphore.WaitAsync().ConfigureAwait(false);
+            try
+            {
+                if (_storage == null)
+                {
+                    return;
+                }
+
+                _applicationMessages.Add(applicationMessage);
+                await SaveAsync().ConfigureAwait(false);
+            }
+            finally
+            {
+                _semaphore.Release();
+            }
+        }
+
+        public async Task RemoveAsync(MqttApplicationMessage applicationMessage)
+        {
+            await _semaphore.WaitAsync().ConfigureAwait(false);
+            try
+            {
+                if (_storage == null)
+                {
+                    return;
+                }
+
+                var index = _applicationMessages.IndexOf(applicationMessage);
+                if (index == -1)
+                {
+                    return;
+                }
+
+                _applicationMessages.RemoveAt(index);
+                await SaveAsync().ConfigureAwait(false);
+            }
+            finally
+            {
+                _semaphore.Release();
+            }
+        }
+
+        private Task SaveAsync()
+        {
+            return _storage.SaveQueuedMessagesAsync(_applicationMessages);
+        }
+    }
+}

MQTTnet.Core/ManagedClient/ReconnectionResult.cs

@@ -0,0 +1,9 @@
+namespace MQTTnet.Core.ManagedClient
+{
+    public enum ReconnectionResult
+    {
+        StillConnected,
+        Reconnected,
+        NotConnected
+    }
+}

MQTTnet.Core/MqttApplicationMessage.cs

@@ -5,6 +5,11 @@ namespace MQTTnet.Core
 {
     public sealed class MqttApplicationMessage
     {
+        public MqttApplicationMessage()
+        {
+        }
+
+        [Obsolete("Use object initializer or _MqttApplicationMessageBuilder_ instead.")]
         public MqttApplicationMessage(string topic, byte[] payload, MqttQualityOfServiceLevel qualityOfServiceLevel, bool retain)
         {
             Topic = topic ?? throw new ArgumentNullException(nameof(topic));
@@ -13,12 +18,12 @@ namespace MQTTnet.Core
             Retain = retain;
         }
 
-        public string Topic { get; }
+        public string Topic { get; set; }
 
-        public byte[] Payload { get; }
+        public byte[] Payload { get; set; }
 
-        public MqttQualityOfServiceLevel QualityOfServiceLevel { get; }
+        public MqttQualityOfServiceLevel QualityOfServiceLevel { get; set; }
 
-        public bool Retain { get; }
+        public bool Retain { get; set; }
     }
 }

MQTTnet.Core/MqttApplicationMessageBuilder.cs

@@ -0,0 +1,114 @@
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Text;
+using MQTTnet.Core.Exceptions;
+using MQTTnet.Core.Protocol;
+
+namespace MQTTnet.Core
+{
+    public class MqttApplicationMessageBuilder
+    {
+        private MqttQualityOfServiceLevel _qualityOfServiceLevel = MqttQualityOfServiceLevel.AtMostOnce;
+        private string _topic;
+        private byte[] _payload;
+        private bool _retain;
+
+        public MqttApplicationMessageBuilder WithTopic(string topic)
+        {
+            _topic = topic;
+            return this;
+        }
+
+        public MqttApplicationMessageBuilder WithPayload(IEnumerable<byte> payload)
+        {
+            if (payload == null)
+            {
+                _payload = null;
+                return this;
+            }
+
+            _payload = payload.ToArray();
+            return this;
+        }
+
+        public MqttApplicationMessageBuilder WithPayload(MemoryStream payload)
+        {
+            if (payload == null)
+            {
+                _payload = null;
+                return this;
+            }
+
+            if (payload.Length == 0)
+            {
+                _payload = new byte[0];
+            }
+            else
+            {
+                _payload = new byte[payload.Length - payload.Position];
+                payload.Read(_payload, 0, _payload.Length);
+            }
+
+            return this;
+        }
+
+        public MqttApplicationMessageBuilder WithPayload(string payload)
+        {
+            if (payload == null)
+            {
+                _payload = null;
+                return this;
+            }
+
+            _payload = string.IsNullOrEmpty(payload) ? new byte[0] : Encoding.UTF8.GetBytes(payload);
+            return this;
+        }
+
+        public MqttApplicationMessageBuilder WithQualityOfServiceLevel(MqttQualityOfServiceLevel qualityOfServiceLevel)
+        {
+            _qualityOfServiceLevel = qualityOfServiceLevel;
+            return this;
+        }
+
+        public MqttApplicationMessageBuilder WithRetainFlag(bool value = true)
+        {
+            _retain = value;
+            return this;
+        }
+
+        public MqttApplicationMessageBuilder WithAtLeastOnceQoS()
+        {
+            _qualityOfServiceLevel = MqttQualityOfServiceLevel.AtLeastOnce;
+            return this;
+        }
+
+        public MqttApplicationMessageBuilder WithAtMostOnceQoS()
+        {
+            _qualityOfServiceLevel = MqttQualityOfServiceLevel.AtMostOnce;
+            return this;
+        }
+
+        public MqttApplicationMessageBuilder WithExactlyOnceQoS()
+        {
+            _qualityOfServiceLevel = MqttQualityOfServiceLevel.ExactlyOnce;
+            return this;
+        }
+
+        public MqttApplicationMessage Build()
+        {
+            if (string.IsNullOrEmpty(_topic))
+            {
+                throw new MqttProtocolViolationException("Topic is not set.");
+            }
+
+            return new MqttApplicationMessage
+            {
+                Topic = _topic,
+                Payload = _payload ?? new byte[0],
+                QualityOfServiceLevel = _qualityOfServiceLevel,
+                Retain = _retain
+            };
+        }
+    }
+}

MQTTnet.Core/MqttApplicationMessageFactory.cs

@@ -1,58 +0,0 @@
-using System;
-using System.Globalization;
-using System.IO;
-using System.Text;
-using MQTTnet.Core.Protocol;
-
-namespace MQTTnet.Core
-{
-    public class MqttApplicationMessageFactory
-    {
-        public MqttApplicationMessage CreateApplicationMessage(string topic, MqttQualityOfServiceLevel qualityOfServiceLevel = MqttQualityOfServiceLevel.AtMostOnce, bool retain = false)
-        {
-            if (topic == null) throw new ArgumentNullException(nameof(topic));
-
-            return CreateApplicationMessage(topic, new byte[0], qualityOfServiceLevel, retain);
-        }
-
-        public MqttApplicationMessage CreateApplicationMessage(string topic, byte[] payload, MqttQualityOfServiceLevel qualityOfServiceLevel = MqttQualityOfServiceLevel.AtMostOnce, bool retain = false)
-        {
-            if (topic == null) throw new ArgumentNullException(nameof(topic));
-
-            if (payload == null)
-            {
-                payload = new byte[0];
-            }
-
-            return new MqttApplicationMessage(topic, payload, qualityOfServiceLevel, retain);
-        }
-
-        public MqttApplicationMessage CreateApplicationMessage<TPayload>(string topic, TPayload payload, MqttQualityOfServiceLevel qualityOfServiceLevel = MqttQualityOfServiceLevel.AtMostOnce, bool retain = false)
-        {
-            if (topic == null) throw new ArgumentNullException(nameof(topic));
-
-            var payloadString = Convert.ToString(payload, CultureInfo.InvariantCulture);
-            var payloadBuffer = string.IsNullOrEmpty(payloadString) ? new byte[0] : Encoding.UTF8.GetBytes(payloadString);
-
-            return CreateApplicationMessage(topic, payloadBuffer, qualityOfServiceLevel, retain);
-        }
-
-        public MqttApplicationMessage CreateApplicationMessage(string topic, Stream payload, MqttQualityOfServiceLevel qualityOfServiceLevel = MqttQualityOfServiceLevel.AtMostOnce, bool retain = false)
-        {
-            if (topic == null) throw new ArgumentNullException(nameof(topic));
-
-            byte[] payloadBuffer;
-            if (payload == null || payload.Length == 0)
-            {
-                payloadBuffer = new byte[0];
-            }
-            else
-            {
-                payloadBuffer = new byte[payload.Length - payload.Position];
-                payload.Read(payloadBuffer, 0, payloadBuffer.Length);
-            }
-
-            return CreateApplicationMessage(topic, payloadBuffer, qualityOfServiceLevel, retain);
-        }
-    }
-}

MQTTnet.Core/MqttApplicationMessageReceivedEventArgs.cs

@@ -1,6 +1,6 @@
 using System;
 
-namespace MQTTnet.Core.Server
+namespace MQTTnet.Core
 {
     public sealed class MqttApplicationMessageReceivedEventArgs : EventArgs
     {

MQTTnet.Core/Packets/MqttPacketExtensions.cs

@@ -12,8 +12,7 @@ namespace MQTTnet.Core.Packets
 
             if (responsePacket is IMqttPacketWithIdentifier responsePacketWithIdentifier)
             {
-                var requestPacketWithIdentifier = packet as IMqttPacketWithIdentifier;
-                if (requestPacketWithIdentifier == null)
+                if (!(packet is IMqttPacketWithIdentifier requestPacketWithIdentifier))
                 {
                     throw new InvalidOperationException("Response packet has PacketIdentifier but request packet does not.");
                 }

MQTTnet.Core/Packets/MqttSubAckPacket.cs

@@ -8,7 +8,7 @@ namespace MQTTnet.Core.Packets
     {
         public ushort PacketIdentifier { get; set; }
 
-        public IList<MqttSubscribeReturnCode> SubscribeReturnCodes { get; set; } = new List<MqttSubscribeReturnCode>();
+        public IList<MqttSubscribeReturnCode> SubscribeReturnCodes { get; } = new List<MqttSubscribeReturnCode>();
 
         public override string ToString()
         {

MQTTnet.Core/Packets/MqttSubscribePacket.cs

@@ -11,7 +11,7 @@ namespace MQTTnet.Core.Packets
 
         public override string ToString()
         {
-            var topicFiltersText = string.Join(",", TopicFilters.Select(f => $"{f.Topic}@{f.QualityOfServiceLevel}"));
+            var topicFiltersText = string.Join(",", TopicFilters.Select(f => f.Topic + "@" + f.QualityOfServiceLevel));
             return nameof(MqttSubscribePacket) + ": [PacketIdentifier=" + PacketIdentifier + "] [TopicFilters=" + topicFiltersText + "]";
         }
     }

MQTTnet.Core/Packets/TopicFilter.cs

@@ -1,17 +0,0 @@
-using MQTTnet.Core.Protocol;
-
-namespace MQTTnet.Core.Packets
-{
-    public sealed class TopicFilter
-    {
-        public TopicFilter(string topic, MqttQualityOfServiceLevel qualityOfServiceLevel)
-        {
-            Topic = topic;
-            QualityOfServiceLevel = qualityOfServiceLevel;
-        }
-
-        public string Topic { get; }
-
-        public MqttQualityOfServiceLevel QualityOfServiceLevel { get; }
-    }
-}

MQTTnet.Core/Serializer/MqttPacketReader.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using System.IO;
 using System.Text;
 using System.Threading;
@@ -13,7 +14,7 @@ namespace MQTTnet.Core.Serializer
     public sealed class MqttPacketReader : BinaryReader
     {
         private readonly ReceivedMqttPacket _receivedMqttPacket;
-        
+
         public MqttPacketReader(ReceivedMqttPacket receivedMqttPacket)
             : base(receivedMqttPacket.Body, Encoding.UTF8, true)
         {
@@ -24,7 +25,13 @@ namespace MQTTnet.Core.Serializer
 
         public static MqttPacketHeader ReadHeaderFromSource(Stream stream, CancellationToken cancellationToken)
         {
-            var fixedHeader = (byte)stream.ReadByte();
+            var buffer = stream.ReadByte();
+            if (buffer == -1)
+            {
+                return null;
+            }
+
+            var fixedHeader = (byte)buffer;
             var controlPacketType = (MqttControlPacketType)(fixedHeader >> 4);
             var bodyLength = ReadBodyLengthFromSource(stream, cancellationToken);
 
@@ -70,6 +77,8 @@ namespace MQTTnet.Core.Serializer
             var multiplier = 1;
             var value = 0;
             byte encodedByte;
+
+            var readBytes = new List<int>();
             do
             {
                 if (cancellationToken.IsCancellationRequested)
@@ -77,14 +86,23 @@ namespace MQTTnet.Core.Serializer
                     throw new TaskCanceledException();
                 }
 
-                encodedByte = (byte)stream.ReadByte();
-                value += (encodedByte & 127) * multiplier;
+                var buffer = stream.ReadByte();
+                readBytes.Add(buffer);
+
+                if (buffer == -1)
+                {
+                    break;
+                }
+
+                encodedByte = (byte)buffer;
+                value += (byte)(encodedByte & 127) * multiplier;
                 multiplier *= 128;
                 if (multiplier > 128 * 128 * 128)
                 {
-                    throw new MqttProtocolViolationException("Remaining length is invalid.");
+                    throw new MqttProtocolViolationException($"Remaining length is invalid (Data={string.Join(",", readBytes)}).");
                 }
             } while ((encodedByte & 128) != 0);
+
             return value;
         }
     }

MQTTnet.Core/Serializer/MqttPacketSerializer.cs

@@ -24,93 +24,21 @@ namespace MQTTnet.Core.Serializer
             using (var stream = new MemoryStream())
             using (var writer = new MqttPacketWriter(stream))
             {
-                var header = new List<byte> { SerializePacket(packet, writer) };
+                var fixedHeader = SerializePacket(packet, writer);
+                var headerBuffer = new List<byte> { fixedHeader };
+                MqttPacketWriter.WriteRemainingLength((int)stream.Length, headerBuffer);
+
+                var header = headerBuffer.ToArray();
                 var body = stream.ToArray();
-                MqttPacketWriter.BuildLengthHeader(body.Length, header);
-                var headerArray = header.ToArray();
-                var writeBuffer = new byte[header.Count + body.Length];
-                Buffer.BlockCopy(headerArray, 0, writeBuffer, 0, headerArray.Length);
-                Buffer.BlockCopy(body, 0, writeBuffer, headerArray.Length, body.Length);
 
-                return writeBuffer;
+                var buffer = new byte[header.Length + body.Length];
+                Buffer.BlockCopy(header, 0, buffer, 0, header.Length);
+                Buffer.BlockCopy(body, 0, buffer, header.Length, body.Length);
+
+                return buffer;
             }
         }
 
-        private byte SerializePacket(MqttBasePacket packet, MqttPacketWriter writer)
-        {
-            if (packet is MqttConnectPacket connectPacket)
-            {
-                return Serialize(connectPacket, writer);
-            }
-
-            if (packet is MqttConnAckPacket connAckPacket)
-            {
-                return Serialize(connAckPacket, writer);
-            }
-
-            if (packet is MqttDisconnectPacket disconnectPacket)
-            {
-                return Serialize(disconnectPacket, writer);
-            }
-
-            if (packet is MqttPingReqPacket pingReqPacket)
-            {
-                return Serialize(pingReqPacket, writer);
-            }
-
-            if (packet is MqttPingRespPacket pingRespPacket)
-            {
-                return Serialize(pingRespPacket, writer);
-            }
-
-            if (packet is MqttPublishPacket publishPacket)
-            {
-                return Serialize(publishPacket, writer);
-            }
-
-            if (packet is MqttPubAckPacket pubAckPacket)
-            {
-                return Serialize(pubAckPacket, writer);
-            }
-
-            if (packet is MqttPubRecPacket pubRecPacket)
-            {
-                return Serialize(pubRecPacket, writer);
-            }
-
-            if (packet is MqttPubRelPacket pubRelPacket)
-            {
-                return Serialize(pubRelPacket, writer);
-            }
-
-            if (packet is MqttPubCompPacket pubCompPacket)
-            {
-                return Serialize(pubCompPacket, writer);
-            }
-
-            if (packet is MqttSubscribePacket subscribePacket)
-            {
-                return Serialize(subscribePacket, writer);
-            }
-
-            if (packet is MqttSubAckPacket subAckPacket)
-            {
-                return Serialize(subAckPacket, writer);
-            }
-
-            if (packet is MqttUnsubscribePacket unsubscribePacket)
-            {
-                return Serialize(unsubscribePacket, writer);
-            }
-
-            if (packet is MqttUnsubAckPacket unsubAckPacket)
-            {
-                return Serialize(unsubAckPacket, writer);
-            }
-
-            throw new MqttProtocolViolationException("Packet type invalid.");
-        }
-
         public MqttBasePacket Deserialize(ReceivedMqttPacket receivedMqttPacket)
         {
             if (receivedMqttPacket == null) throw new ArgumentNullException(nameof(receivedMqttPacket));
@@ -121,103 +49,90 @@ namespace MQTTnet.Core.Serializer
             }
         }
 
+        private byte SerializePacket(MqttBasePacket packet, MqttPacketWriter writer)
+        {
+            switch (packet)
+            {
+                case MqttConnectPacket connectPacket: return Serialize(connectPacket, writer);
+                case MqttConnAckPacket connAckPacket: return Serialize(connAckPacket, writer);
+                case MqttDisconnectPacket _: return SerializeEmptyPacket(MqttControlPacketType.Disconnect);
+                case MqttPingReqPacket _: return SerializeEmptyPacket(MqttControlPacketType.PingReq);
+                case MqttPingRespPacket _: return SerializeEmptyPacket(MqttControlPacketType.PingResp);
+                case MqttPublishPacket publishPacket: return Serialize(publishPacket, writer);
+                case MqttPubAckPacket pubAckPacket: return Serialize(pubAckPacket, writer);
+                case MqttPubRecPacket pubRecPacket: return Serialize(pubRecPacket, writer);
+                case MqttPubRelPacket pubRelPacket: return Serialize(pubRelPacket, writer);
+                case MqttPubCompPacket pubCompPacket: return Serialize(pubCompPacket, writer);
+                case MqttSubscribePacket subscribePacket: return Serialize(subscribePacket, writer);
+                case MqttSubAckPacket subAckPacket: return Serialize(subAckPacket, writer);
+                case MqttUnsubscribePacket unsubscribePacket: return Serialize(unsubscribePacket, writer);
+                case MqttUnsubAckPacket unsubAckPacket: return Serialize(unsubAckPacket, writer);
+                default: throw new MqttProtocolViolationException("Packet type invalid.");
+            }
+        }
+
         private static MqttBasePacket Deserialize(MqttPacketHeader header, MqttPacketReader reader)
         {
             switch (header.ControlPacketType)
             {
-                case MqttControlPacketType.Connect:
-                    {
-                        return DeserializeConnect(reader);
-                    }
-
-                case MqttControlPacketType.ConnAck:
-                    {
-                        return DeserializeConnAck(reader);
-                    }
-
-                case MqttControlPacketType.Disconnect:
-                    {
-                        return new MqttDisconnectPacket();
-                    }
-
-                case MqttControlPacketType.Publish:
-                    {
-                        return DeserializePublish(reader, header);
-                    }
-
-                case MqttControlPacketType.PubAck:
-                    {
-                        return new MqttPubAckPacket
-                        {
-                            PacketIdentifier = reader.ReadUInt16()
-                        };
-                    }
-
-                case MqttControlPacketType.PubRec:
-                    {
-                        return new MqttPubRecPacket
-                        {
-                            PacketIdentifier = reader.ReadUInt16()
-                        };
-                    }
-
-                case MqttControlPacketType.PubRel:
-                    {
-                        return new MqttPubRelPacket
-                        {
-                            PacketIdentifier = reader.ReadUInt16()
-                        };
-                    }
-
-                case MqttControlPacketType.PubComp:
-                    {
-                        return new MqttPubCompPacket
-                        {
-                            PacketIdentifier = reader.ReadUInt16()
-                        };
-                    }
-
-                case MqttControlPacketType.PingReq:
-                    {
-                        return new MqttPingReqPacket();
-                    }
-
-                case MqttControlPacketType.PingResp:
-                    {
-                        return new MqttPingRespPacket();
-                    }
-
-                case MqttControlPacketType.Subscribe:
-                    {
-                        return DeserializeSubscribe(reader);
-                    }
-
-                case MqttControlPacketType.SubAck:
-                    {
-                        return DeserializeSubAck(reader);
-                    }
-
-                case MqttControlPacketType.Unsubscibe:
-                    {
-                        return DeserializeUnsubscribe(reader);
-                    }
-
-                case MqttControlPacketType.UnsubAck:
-                    {
-                        return new MqttUnsubAckPacket
-                        {
-                            PacketIdentifier = reader.ReadUInt16()
-                        };
-                    }
-
-                default:
-                    {
-                        throw new MqttProtocolViolationException(
-                            $"Packet type ({(int)header.ControlPacketType}) not supported.");
-                    }
+                case MqttControlPacketType.Connect: return DeserializeConnect(reader);
+                case MqttControlPacketType.ConnAck: return DeserializeConnAck(reader);
+                case MqttControlPacketType.Disconnect: return new MqttDisconnectPacket();
+                case MqttControlPacketType.Publish: return DeserializePublish(reader, header);
+                case MqttControlPacketType.PubAck: return DeserializePubAck(reader);
+                case MqttControlPacketType.PubRec: return DeserializePubRec(reader);
+                case MqttControlPacketType.PubRel: return DeserializePubRel(reader);
+                case MqttControlPacketType.PubComp: return DeserializePubComp(reader);
+                case MqttControlPacketType.PingReq: return new MqttPingReqPacket();
+                case MqttControlPacketType.PingResp: return new MqttPingRespPacket();
+                case MqttControlPacketType.Subscribe: return DeserializeSubscribe(reader);
+                case MqttControlPacketType.SubAck: return DeserializeSubAck(reader);
+                case MqttControlPacketType.Unsubscibe: return DeserializeUnsubscribe(reader);
+                case MqttControlPacketType.UnsubAck: return DeserializeUnsubAck(reader);
+                default: throw new MqttProtocolViolationException($"Packet type ({(int)header.ControlPacketType}) not supported.");
             }
         }
 
+        private static MqttBasePacket DeserializeUnsubAck(MqttPacketReader reader)
+        {
+            return new MqttUnsubAckPacket
+            {
+                PacketIdentifier = reader.ReadUInt16()
+            };
+        }
+
+        private static MqttBasePacket DeserializePubComp(MqttPacketReader reader)
+        {
+            return new MqttPubCompPacket
+            {
+                PacketIdentifier = reader.ReadUInt16()
+            };
+        }
+
+        private static MqttBasePacket DeserializePubRel(MqttPacketReader reader)
+        {
+            return new MqttPubRelPacket
+            {
+                PacketIdentifier = reader.ReadUInt16()
+            };
+        }
+
+        private static MqttBasePacket DeserializePubRec(MqttPacketReader reader)
+        {
+            return new MqttPubRecPacket
+            {
+                PacketIdentifier = reader.ReadUInt16()
+            };
+        }
+
+        private static MqttBasePacket DeserializePubAck(MqttPacketReader reader)
+        {
+            return new MqttPubAckPacket
+            {
+                PacketIdentifier = reader.ReadUInt16()
+            };
+        }
+
         private static MqttBasePacket DeserializeUnsubscribe(MqttPacketReader reader)
         {
             var packet = new MqttUnsubscribePacket
@@ -298,7 +213,7 @@ namespace MQTTnet.Core.Serializer
                 throw new MqttProtocolViolationException("Protocol name is not supported.");
             }
 
-            var protocolLevel = reader.ReadByte();
+            reader.ReadByte(); // Skip protocol level
             var connectFlags = reader.ReadByte();
 
             var connectFlagsReader = new ByteReader(connectFlags);
@@ -321,11 +236,13 @@ namespace MQTTnet.Core.Serializer
 
             if (willFlag)
             {
-                packet.WillMessage = new MqttApplicationMessage(
-                    reader.ReadStringWithLengthPrefix(),
-                    reader.ReadWithLengthPrefix(),
-                    (MqttQualityOfServiceLevel)willQoS,
-                    willRetain);
+                packet.WillMessage = new MqttApplicationMessage
+                {
+                    Topic = reader.ReadStringWithLengthPrefix(),
+                    Payload = reader.ReadWithLengthPrefix(),
+                    QualityOfServiceLevel = (MqttQualityOfServiceLevel)willQoS,
+                    Retain = willRetain
+                };
             }
 
             if (usernameFlag)
@@ -373,6 +290,8 @@ namespace MQTTnet.Core.Serializer
 
         private static void ValidateConnectPacket(MqttConnectPacket packet)
         {
+            if (packet == null) throw new ArgumentNullException(nameof(packet));
+
             if (string.IsNullOrEmpty(packet.ClientId) && !packet.CleanSession)
             {
                 throw new MqttProtocolViolationException("CleanSession must be set if ClientId is empty [MQTT-3.1.3-7].");
@@ -381,6 +300,8 @@ namespace MQTTnet.Core.Serializer
 
         private static void ValidatePublishPacket(MqttPublishPacket packet)
         {
+            if (packet == null) throw new ArgumentNullException(nameof(packet));
+
             if (packet.QualityOfServiceLevel == 0 && packet.Dup)
             {
                 throw new MqttProtocolViolationException("Dup flag must be false for QoS 0 packets [MQTT-3.3.1-2].");
@@ -468,21 +389,6 @@ namespace MQTTnet.Core.Serializer
             return MqttPacketWriter.BuildFixedHeader(MqttControlPacketType.PubRel, 0x02);
         }
 
-        private static byte Serialize(MqttDisconnectPacket packet, MqttPacketWriter writer)
-        {
-            return SerializeEmptyPacketAsync(MqttControlPacketType.Disconnect, writer);
-        }
-
-        private static byte Serialize(MqttPingReqPacket packet, MqttPacketWriter writer)
-        {
-            return SerializeEmptyPacketAsync(MqttControlPacketType.PingReq, writer);
-        }
-
-        private static byte Serialize(MqttPingRespPacket packet, MqttPacketWriter writer)
-        {
-            return SerializeEmptyPacketAsync(MqttControlPacketType.PingResp, writer);
-        }
-
         private static byte Serialize(MqttPublishPacket packet, MqttPacketWriter writer)
         {
             ValidatePublishPacket(packet);
@@ -594,14 +500,13 @@ namespace MQTTnet.Core.Serializer
             return MqttPacketWriter.BuildFixedHeader(MqttControlPacketType.Unsubscibe, 0x02);
         }
 
-        private static byte Serialize(MqttUnsubAckPacket packet, MqttPacketWriter writer)
+        private static byte Serialize(IMqttPacketWithIdentifier packet, BinaryWriter writer)
         {
             writer.Write(packet.PacketIdentifier);
-
             return MqttPacketWriter.BuildFixedHeader(MqttControlPacketType.UnsubAck);
         }
 
-        private static byte SerializeEmptyPacketAsync(MqttControlPacketType type, MqttPacketWriter writer)
+        private static byte SerializeEmptyPacket(MqttControlPacketType type)
         {
             return MqttPacketWriter.BuildFixedHeader(type);
         }