.NET External Communication

Question

I used the term "External Communication" simply because I do not mind which method I need to use to be able to send a simple message like "hey, how's it going?" to another person on a different computer who's also running my application.

I've tried literally hundreds of samples, edited them, corrected various errors, came up with some of my own stuff, and nothing ever works.

I can send and receive messages to myself on the same computer but I can never be able to get a friend to connect to my server program. Using port 80, or 8080, or 1009 but i've also tried many other numbers too lol - no luck! I've read documentation many times, and several articles from all over the web and also used those examples, still no luck.

Does anybody have any idea on how i can send and receieve simple messages between computers?

Answer 1

Is this on a Lan or over the public internet? I ask as firewall rules may be different in either case.

Use a packet sniffer like wireshark to see what packets are travelling on the source and destination ports on both PCs.

Answer 2

Do you have a firewall installed on your computer? Rembeber that newer versions of Windows come with a firewall installed and working.

In case you haven't seen it: Peer-to-Peer Programming with WCF and .NET Framework 3.5

Answer 3

Sounds like a classic case for a WCF app with peer-to-peer binding.

Check out some of those links for articles and blog post that show you have to do it:

• Peer-to-peer programming with WCF in .NET Framework 3.5
• Building a REALLY simple WCF P2P application
• Chosing the right WCF binding
• A simple peer to peer chat application using WCF netPeerTcpBinding

Marc