The WebSocketListener class provides simple methods that listen for and accept incoming WebSocket connection requests asynchronously. It is a lightweight listener with an API very similar to the System.Net.TcpListener class. It does not use the Microsoft's System.Net.WebSockets namespace. WebSocketListener has been designed to provide WebSocket connectivity to other applications, in the same way that System.Net.TcpListener provides TCP connectivity. It is not a communication framework on its own and it does not provide any kind of publisher/subscriber pattern or reliable messaging beyond TCP.