Programming for Multiple Networks
Learn about application listening from a socket, multihomed servers, and physical hosts.
Listening on a socket
This multitude of interfaces affects the application software. By default, an application that listens on a socket will listen for connection attempts on any interface. Language libraries always have an “easy” version of listening on a socket. The easy version just opens a socket on every interface on the host. Bad news! Instead, we have to do it the hard way and specify which IP address we are opening the socket for: