SpaceFibre is a spacecraft onboard data link and network technology being developed by University of Dundee for the European Space Agency (ESA), which runs over both copper and fibre optic cables. Initially targeted at very high data rate payloads such as Synthetic Aperture Radar (SAR) and multi-spectral imaging instruments, SpaceFibre is capable of fulfilling a wider set of spacecraft onboard communications applications because of its inbuilt QoS and FDIR capabilities and its backwards compatibility with the ubiquitous SpaceWire technology. SpaceFibre operates at 2.5 Gbits/s providing 12 times the throughput of a SpaceWire link with current flight qualified technology and allowing data from multiple SpaceWire devices to be concentrated over a single SpaceFibre link. This substantially reduces cable harness mass and simplifies redundancy strategies. The innovative QoS mechanism in SpaceFibre provides concurrent bandwidth reservation, priority and scheduled QoS. This simplifies spacecraft system engineering through integrated quality of service (QoS), which reduces system engineering costs and streamlines integration and test. Novel integrated FDIR support provides galvanic isolation, transparent recovery from transient errors, error containment in virtual channels and frames, and “Babbling Idiot” protection. SpaceFibre enhances onboard network robustness through its inherent FDIR and graceful degradation techniques incorporated in the network hardware. This simplifies system FDIR software, reducing development and system validation time and cost. SpaceFibre includes low latency event signalling and time distribution with broadcast messages. This enables a single network to be used for several functions including: transporting very high data rate payload data, carrying SpaceWire traffic, deterministic delivery of command/control information, time distribution and event signalling. SpaceFibre is backwards compatible with existing SpaceWire equipment at the packet level allowing simple interconnection of SpaceWire devices into a SpaceFibre network and enabling that equipment to take advantage of the QoS and FDIR capabilities of SpaceFibre.