Netperf is a benchmark that can be used to measure the performance of many different types of networking. It provides tests for both unidirecitonal throughput, and end-to-end latency. The environments currently measureable by netperf include:

• TCP and UDP via BSD Sockets for both IPv4 and IPv6
• DLPI
• Unix Domain Sockets
• SCTP for both IPv4 and IPv6

Netperf in it’s default test will measure bulk data transfer performance. This is also referred to as “stream” or “unidirectional stream” performance. Essentially, these tests will measure how fast one system can send data to another and/or how fast that other system can receive it.

For a more detaailed manual check out: http://www.netperf.org/netperf/training/Netperf.html
Homepage: http://www.netperf.org/netperf/