Enabling technologies for the SpaceFibre protocol: the European Space Agency standard for future on-board satellite high-speed data networks

SATELLITES play a fundamental role in everyone’s life. From earth observation to telecommunication and science missions, they both improve the quality of our lives and help us to discover the secrets of the universe. But they also are a formidable challenge for engineers and scientists coming from many different fields. Among the others, one of the critical points in the design of a satellite is its on-board network used to interconnect the different components. The continuous evolution of satellite payloads requires more and more bandwidth to the underlying links, well beyond 1Gbps, that cannot be satisfied with standardized technologies. The successful and widely-used SpaceWire is indeed limited to 400Mbps and it cannot be used for forthcoming instruments requiring higher data-rates. To overcome this problem, the European Space Agency (ESA) is supporting the development of a new protocol, SpaceFibre, with a data-rate up to 6.25Gbps per lane and which includes advanced features like a flexible Quality of Service (QoS) and a Fault Detection Isolation and Recovery (FDIR) mechanism. However, SpaceFibre is a modern and not yet standardized protocol and it poses several research challenges, in particular regarding its Network Layer and the support to the QoS from an end-to-end point of view. To this aim the European Space Agency, together with the company IngeniArs s.r.l., has sponsored a Ph.D. scholarship in the framework of a Networking/Partnering Initiative (NPI) in order to support the standardization process of SpaceFibre and its adoption by industry. A full-fledged SpaceFibre test equipment called SpaceART has been developed in collaboration with IngeniArs s.r.l., which allows to deeply analyze a SpaceFibre or a SpaceWire link thanks to its advanced hardware peripherals and a complete and versatile host software. SpaceART allows to transfer custom data from and to a Host PC in real-time thanks to its fast PCIe connection. Alternatively, it can be connected to the Host PC through a versatile Gigabit Ethernet port. The availability of such a device is fundamental for every company willing to develop SpaceFibre-related products, in order to test and verify their own equipment. In order to help the study of the Network Layer, which was the most critical section of the standard, and to support the development of new upper layer protocols for Space-Fibre, also a network simulator called SHINe has been implemented. SHINe allows to quickly deploy SpaceFibre and SpaceWire nodes and simulate the resulting network to study the behavior of the protocols and to extract typical network measurements, such as packet latency or blocking time. This is key for every company willing to evaluate the performance of on-board SpaceWire/SpaceFibre data networks. Finally, a complete SpaceFibre Routing Switch has been designed and implemented in VHDL. The Routing Switch permits to study, from a practical standpoint, the feasibility of the current Network Layer. The Routing Switch implements all the features foreseen by the SpaceFibre standard, plus additional ad-hoc developed mechanisms to improve network reliability and it has been synthesized for different FPGAs. It is also a fundamental step in the roadmap to a wider adoption of SpaceFibre.