From the publisher website or publicity

Web Polygraph is a freely available benchmarking tool for caching proxies, origin server accelerators, L4/7 switches, content filters, and other Web intermediaries. Polygraph's features include:

 *high-performance HTTP clients and servers
 *realistic HTTP and SSL traffic generation
 *flexible content simulation
 *ready-to-use standard workloads
 *powerful domain-specific configuration language
 *portable open-source implementation

Keywords
benchmark
benchmarking
cache
caching
caching proxies
content filters
freeware
http
http clients
http servers
L4 7
L4 7 switch
open-source
polygraph
proxies
web intermediaries
Web Polygraph
web testing

Related Articles
Web-Testing and e-Commerce
Equity floor
Equity cap
Customized benchmarks
Current-coupon issues
Break-even payment rate

Other tools that may interest you by area:-

Open Source tools

Load Testing tools

Stress Testing tools

Testing Performance tools

Automated Testing tools

Vendor: Web Polygraph