Iperf is a tool to measure IP bandwidth using UDP or TCP. It allows for tuning various parameters, and reports bandwidth, delay jitter, and packet loss. It supports IPv6 and multicast. Iperf was developed by NLANR/DAST as a modern alternative for measuring maximum TCP and UDP bandwidth performance. Iperf allows the tuning of various parameters and UDP characteristics. Iperf reports bandwidth, delay jitter, datagram loss.