SpaceWire protocol ID: what does it means to you?

SpaceWire is becoming a popular solution for satellite high-speed data buses, because it is a simple standard that provides great flexibility for a wide range of system requirements. It is simple in packet format and protocol, allowing users to easily tailor their implementation for their specific application. Some of the attractive aspects of SpaceWire that make it easy to implement also make it hard for future reuse. Protocol reuse is difficult because SpaceWire does not have a defined mechanism to communicate with the higher layers of the protocol stack. This has forced users of SpaceWire to define unique packet formats and define how these packets are to be processed. SpaceWire also has two different packet formats that may be presented to the end user, one with a destination address and one without. This further complicates the system design, as both options cannot be supported. Each particular mission writes it's own interface control document (ICD) and tailors SpaceWire for it's specific requirements making reuse difficult. Part of the reason for this habit may be because engineers typically optimize designs for their own requirements in the absence of a standard. This is an inefficient use of project resources and costs more to develop missions