Chat Client Server across the network using Winsocket 2 and C++?

I am Developing a chat system that consists of multiple clients and a server.

The clients should开发者_JAVA百科 discover the server by sending a broadcast message, which the server will respond to, sending back to the client it's IP and port.

The problem is when I connect to the internet using a USB stick (USB modem), the broadcast message is sent by the client, but the server could not send information back to the client.

Is there any way to limit the chat program to a specified network interface?

Does anybody have any other suggestions?

You can use Wireshark to look at the network traffic. That could help you troubleshoot this situation.

http://www.wireshark.org/