Over the past few days I’ve been looking at testing WCF services using a network socket based approach. I got a proof-of-concept demo program up and running. As usual, there were several glitches along the way. The key to resolving most of these glitches was to examine network traffic between a WCF service and a client, using a traffic examination tool. I used Fiddler, which has come in handy many times. See screenshot below. In a larger perspective, software testing is often all about understanding some software system. Once a system is fully understood, testing the system manually or programmatically usually comes pretty easily (relatively anyway). I am writing up an article on the technique of testing WCF services using sockets for MSDN Magazine and I’m happy with the way it is going.