VB packet sniffer code?

[Cerksees]

Does anyone know of any visual basic code for a packet sniffer? I have a legit need for a program that knows the address and socket of two machines that are communicating, and can respond to specific communcations between the two machines. The program will basically be a watcher to notify the programmer of problems with the client/server code - hopefully before the user knows.

Any help would certainly be appreciated.