[erlang-questions] How to implement multiple sockets per client?

[James Cone]

If the end-to-end assumption held, then the client could listen and give 
the server details about where to connect the other socket to, thereby 
guaranteeing that the sockets were matched.

Alternatively, for each incoming connection on the main listen socket, 
the server could listen on another port and send details to the client.

I'm still not convinced, like Bob, that I know what the two sockets are 
for, that can't be done better with one socket.