Client server with authentication in C# .Net (i.e. SslStream)

Hi, I’m looking for a programmer to help out on a server-client setup within C# winforms. Preferred with [login to view URL] The basics: 1. The server must be able to handle multiple clients. 2. All clients must be dealt with in a different thread. 3. Reading from and writing to the client must be done async. 4. The client must login on connection (and with wrong credentials the connection must be closed). The username and password should be in memory of the server on POC (just a simple dictionary, for instance. This will be done in a better way later on) 5. SSL / TLS must be used. 6. Transfer of binary array streams. 7. Preferred to be able to use different languages to connect to the server as well, if easy to implement. 8. All server code must be within a winform application. No services allowed as a “middleman”. No extra packages without source code. (Basically like implementing a TCP server with TcpListener) 9. Must be able to whitelist and/or blacklist IP addresses. 10. When a client connects, the server needs to know (easy, but makes sense) 11. When a client tries to connect, but the server if not running, the client must continue trying to connect. Also if the client was connected, but for some reason the server becomes unavailable, the client must notice that a.s.a.p. and as soon as the server is available again, auto-reconnect the client to the server. Use bool in the client class to see whether or not the client is connected. 12. Solution must be made in .Net 4.7.2. All code must be available on delivery. Basically it will be used to update client GUI based on info on the server and the client can send some info (interaction) to the server. Connection and handling must be done ‘real-time’. Please let me know you game plan and techniques you’re going to use. Which .Net classes etc. etc. Please add a simplified schematic plan with your bid. Kind regards Matthijs