According to Glenn Rakow, NASA’s SpaceWire development lead at Goddard Space Flight Center in Maryland, this flexible, modular, and reusable design allows aerospace companies to standardize their designs. “SpaceWire lets you create one design that you can go to every time, for every mission,” Rakow said.

NASA Goddard’s SpaceWire design is the first and most mature of its kind in the United States. New features and enhancements to the NASA SpaceWire core make the design more suitable for spaceflight applications. A sophisticated verification environment includes directed and random testing, helping to detect hard-to-find design bugs and making the design simple to maintain and update. Not all features are included in the SpaceWire standard, but Goddard’s design may be configured so that it is completely compatible with it. These significant advantages enable easy system integration and testing of SpaceWire designs while improving reliability and reducing complexity.

Compared to Ethernet networks with pre-set link rates, SpaceWire offers flexible link rates, helping save power and providing more options for high-speed applications. In addition, the standard is topology-independent, meaning that connections between routers or network fabrics can be fashioned in nearly any way that suits the design’s needs. Finally, SpaceWire doesn’t define a rigid data-packet structure. “It’s very scaled down and simple, so it gives the system engineer a lot of flexibility in developing additional protocols,” said Rakow.

NASA Goddard also developed a unique SpaceWire linkand- switch implementation. This new design provides for a standard that enables high- and lowrate communication between avionics systems over a network architecture using a first-in/firstout (FIFO) interface. This significant advancement helps reduce the complexity of communication over satellite architecture applications and other spaceflight systems, while improving speed and reliability.