Question about building a server/client chat application

Hello,

I wanna make a client/server chat application using C# (first I was thinking about using Java), with sockets, TCP, etc.

I want to implement these functionalities: send message, send files and maybe audio and video streaming.

But I have a question can I make this to work on different networks? In the same network, or on the same computer as I saw will not be a problem.

 

Thanks!