ISA Server 2006 SP1 - Traffic Simulator and Diagnostic Logging
Traffic Simulator and the built in Diagnostic Logging capabilities are two new features included in ISA Server 2006 SP1. Today Dr Tom Shinder released the part 2 of the deep dive explanation about those features. I strongly recommend you to read both articles and get the full understanding of how each feature works.
Your New ISA Firewall: ISA 2006 Service Pack 1 (Part 1)