Iperf

iperf, Iperf, or iPerf, is a tool for <a href="/facts/Network_performance/ALjfw5Nn">network performance</a> measurement and tuning. It is a <a href="/facts/Cross-platform_software/16zqdvNR">cross-platform tool</a> that can produce standardized performance measurements for any network. iperf has <a href="/facts/Client_(computing)/u0wlVsWI">client</a> and <a href="/facts/Server_(computing)/dEaYFD7r">server</a> functionality, and can create <a href="/facts/Data_stream/57yDhBCd">data streams</a> to measure the <a href="/facts/Throughput/6zAUsXqw">throughput</a> 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 <a href="/facts/Transmission_Control_Protocol/WW4sPrt9">Transmission Control Protocol</a> (TCP) or <a href="/facts/User_Datagram_Protocol/dxLU0D6q">User Datagram Protocol</a> (UDP):

<ul><li>UDP: When used for testing UDP capacity, iperf allows the user to specify the <a href="/facts/Datagram/TMHVctMz">datagram</a> size and provides results for the datagram throughput and the <a href="/facts/Packet_(information_technology)/xCYf8SJu">packet</a> loss.</li>
<li>TCP: When used for testing TCP capacity, iperf measures the throughput of the payload. iperf uses 1024 × 1024 for <a href="/facts/Mebibyte/BNHUp9Qq">mebibytes</a> and 1000 × 1000 for <a href="/facts/Megabyte/RBF4XpWb">megabytes</a>.</li></ul>
iperf is <a href="/facts/Open-source_software/HzTaB8E9">open-source software</a> written in <a href="/facts/C_(programming_language)/Ky2No763">C</a>, and it runs on various platforms including <a href="/facts/Linux/9FvCKSTq">Linux</a>, <a href="/facts/Unix/0pNL2seI">Unix</a> and <a href="/facts/Windows_(Operating_system)/bwhAhuSL">Windows</a> (either natively or inside <a href="/facts/Cygwin/0ANCmAgH">Cygwin</a>). The availability of the <a href="/facts/Source_code/o9J6Jv23">source code</a> enables the user to scrutinize the measurement methodology.
iperf is a compatible reimplementation of the <a href="/facts/Ttcp/E3waPGb6">ttcp</a> program that was developed at the <a href="/facts/National_Center_for_Supercomputing_Applications/vNNK19se">National Center for Supercomputing Applications</a> at the <a href="/facts/University_of_Illinois/gusw7HoS">University of Illinois</a> by the Distributed Applications Support Team (DAST) of the National Laboratory for Applied Network Research (NLANR), which was shut down on December 31, 2006, on termination of funding by the United States <a href="/facts/National_Science_Foundation/FlDT8TbW">National Science Foundation</a>.

Iperf open-in-new

Iperf