•IT Decision Guru
–http://www.opnet.com/products/itdg/home.html
•NetCracker
–http://www.netcracker.com/index.html
•NetRule
–http://www.analyticalengines.com/tour.htm
•Network Associates Sniffer
•www.sniffer.com
•Snort
•www.snort.org
•TCPDump
Sniffers + Network Design/Analysis Tools
Characteristics:
Utilize a sniffer to build DB of  packet streams,
Feed into Design/Modeling Tool to observe loads, flows, statistics – can usually interpret multiple protocols, equipment types

Benefits
Good for modeling Availability:
“What ifs” on host firewall loads, etc,
Loads on Authentication Servers,
Unusual Traffic Analysis
Visualization, compacting loads of traffic into a single visual

Drawbacks:
Fall short on modeling memory, software execution
Requires massive storage and processing power to collect/store data & then run the analysis
Expensive: Design tools $15000, Sniffers - similar


http://www.sniffer.com/