Developed in 1999 under the auspices of the European Space Agency, SpaceWire answered a longstanding spaceflight problem: no standard, high-speed communications protocol existed for flight electronics. Therefore, all spaceflight electronic payloads (such as processing units and onboard computers) were customdesigned, which resulted in long development periods, high costs, and elevated risks. The SpaceWire standard was developed as a network of nodes and routers interconnected through bidirectional, high-speed serial links, limiting the customdesign problem by designing a standard with flexibility, modularity, and reusability.

SpaceWire is defined in the European Cooperation for Space Standardization standard ECSSE50- 12A. The SpaceWire standard was authored by Steve Parkes of the University of Dundee, with contributions from individuals within the European Space Agency (ESA), European Space Industry, NASA, and academia. SpaceWire is the standard for high-speed links and networks for use onboard spacecraft to ease the integration of sensors, processing units, telemetry subsystems, and other micrcoelectronics, and is applicable for spacecraft missions, military hardware systems, and bus systems.

According to the ESA, the purpose of the SpaceWire standard is to facilitate construction of high-performance onboard data handling systems, reduce system integration costs, promote compatibility between data handling equipment and subsystems, and encourage re-use of data handling equipment across several different missions. The SpaceWire standard ensures that equipment is compatible at both the component and subsystem levels.

SpaceWire equipment is connected together using SpaceWire links that are serial, high-speed, bi-directional, and full-duplex. Application information is sent along a SpaceWire link in discrete packets, and control and time information also can be sent along SpaceWire links. SpaceWire supports many different payload processing architectures using point-to-point links and SpaceWire routing switches.