When debugging network programming code the use of a data inspector (packet sniffing tools) is invaluable.
These are the tools we use during the development of our RIA:
ServiceCapture runs on your pc and captures all HTTP traffic sent from your browser or IDE. It is designed to help Rich Internet Application(RIA) developers in the debugging, analysis, and testing of their applications.
Charles is an HTTP proxy / HTTP monitor / Reverse Proxy that enables a developer to view all of the HTTP traffic between their web browser and the Internet. This includes requests, responses and the HTTP headers (which contain the cookies and caching information). View SSL communication in plain text. HTTP/1.1 support.
Wireshark is the world’s foremost network protocol analyzer, and is the de facto (and often de jure) standard across many industries and educational institutions.
Fiddler is a HTTP Debugging Proxy which logs all HTTP traffic between your computer and the Internet. Fiddler allows you to inspect all HTTP Traffic, set breakpoints, and “fiddle” with incoming or outgoing data. Fiddler includes a powerful event-based scripting subsystem, and can be extended using any .NET language.