Implementing ISA 2004 - Good port monitor programs?

[Mr.Guvernment]

Hello again

i am looking to implement MS ISA server 2004 for a network and i want to know of a good port monitor program that i can use on client computers (about 17) to log what ports are being used so that i can be sure i do not block any neccessary resources.

Preferably a port monitor that doesnt just list the port, but what program /applications is trying to acess it... ideally a program that has a central management system so i could monitor the systems in the network from one computer..

thanks again for the help