Iperf

Iperf is a widely-used tool for network performance measurement and tuning. It is significant as a cross-platform tool that can produce standardized performance measurements for any network. Iperf has client and server functionality, and can create data streams to measure the throughput between the two ends in one or both directions. Typical Iperf output contains a time-stamped report of the amount of data transferred and the throughput measured.

The data streams can be either Transmission Control Protocol (TCP) or User Datagram Protocol (UDP):

• UDP: When used for testing UDP capacity, Iperf allows the user to specify the datagram size and provides results for the datagram throughput and the packet loss.
• TCP: When used for testing TCP capacity, Iperf measures the throughput of the payload. Iperf uses 1024 × 1024 for megabytes and 1000 × 1000 for megabits.

Iperf is open-source software written in C, and it runs on various platforms including Linux, Unix and Windows (either natively or inside Cygwin^[1]). The availability of the source code enables the user to scrutinize the measurement methodology.

Iperf is a compatible reimplementation of the ttcp program that was developed at the National Center for Supercomputing Applications at the University of Illinois by the Distributed Applications Support Team (DAST) of the National Laboratory for Applied Network Research (NLANR), which was shut down on December 31, 2006, due to termination of funding by the United States' National Science Foundation.

iperf3

Iperf3 is rewrite of iperf from scratch to create a smaller, simpler code base and a library version of the functionality that can be used in other programs. Iperf3 was started in 2009, with the first release in January 2014. The website states: "iperf3 is not backwards compatible with iperf2.x".

Graphical user interface

There is a graphical user interface (GUI) front end available called jperf.^[2] However, the command shell remains the preferred method of use. ^[3]

See also

• Netperf
• Nuttcp
• NetPIPE
• bwping
• Flowgrind
• Measuring network throughput
• Packet generation model

Public test servers

• http://acd.net ACD.net: iperf.acd.net
• http://sct.gob.mx SCT: 159.16.237.138 -p 8001 TCP & -p 8002 UDP

References

• Measure Network Performance with iperf (Part 1), (Part 2), article published by Enterprise Networking Planet
• Measuring end-to-end bandwidth with Iperf using Web100, whitepaper on modifications to Iperf to be less intrusive

External links

• iperf3 site.
• iperf2 site.
  • JPerf, graphical frontend.
• iperf.fr, list of public iperf servers and download iperf pre-compiled binaries.