Multi Client TCP Server

Okay, your problem is easy.. but will you tell me where do you need help? Or do you want a complete solution for this?

One more thing, you can check the following article: http://www.codeproject.com/csharp/tcpclientserver.asp
It's a simple client-server connection using TCP.. And for your second problem, just think that a server can also act as a client to another server. Just connect to other server and send any data you want.

Thanks for your response,

It is not quite as simple as that example (which i have seen before, but thanks for the link). The server probibly needs to be multi-threaded so it can continuesly listen for new connections, thats where the confusion sets in.

Thanks,
Avery

Well, since I don't have a ready sample for you, you better start coding and ask when you're stuck.. I mean, there are a few things you should know. I see that you already know about System.Net, System.Net.Sockets and simple socket programming. You'll just have to create a listener using TcpListener, start listening.. and when a client connects to your listener, you will Accept() it and pass this Socket object to a new thread. That's it.. Your thread will take care of the client. And also you can do some messaging between threads and your main thread (using delegates, events).
I suggest you to create a listener thread, so your server will always be listening.
So, your server application will be something like this:

ClientThread ct;
Thread t;
TcpListener listener = new TcpListener( IPAddress.Any, 5678 );
while( true )
{
    listener.Start();
    Socket s = listener.AcceptSocket();
    ct = new ClientThread( s, this );
    t = new Thread( new ThreadStart( ct.Run ) );
}

public class ClientThread
{
    Socket s = null;
    Object parent = null;

    public ClientThread( Socket _s, Object _parent )
    {
        s = _s;
        parent = _parent;
    }

    public void Run()
    {
        // Do your client work here... possibly an infinite loop with read operation,
        // processing them etc...
    }
}

The above code is just written here.. I didn't test it, there might be many errors/warnings.. just look as a pseudo-code..

Caner