Netperf is the de-facto standard for network bandwidth testing between two hosts on a network. It blasts TCP data from a client host to a server host. This is different than transferring a file over the network, as you avoid any disk bottlenecks, and are using a standardized client and server for testing.
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
