Allocation of Service Types and Subtypes

The PUS provides a standard set of services that are targeted for communication between spacecraft and ground systems. Many of them may not be applicable to on-board communication between applications. However, nothing precludes their use in a JAS-based system.

The PUS can be extended to add additional functionality to existing services as well as creating new services. Service types 0 to 127 are reserved for PUS and service types 128 to 255 can be used for mission specific services. Within the standard PUS services, subtypes 0 to 127 are reserved for PUS and subtypes 128 to 255 can be used for mission specific services. Within mission specific services, all subtypes (0 to 255) are available for mission-specific use.

There is no expectation that every project must use the same services. Each project should be able to tailor some amount of services for their needs. So, the PUS mission-specific service types and subtypes need to be further allocated into JAS and project specific sets. The following table shows how the service type and subtype values will be allocated to JAS and other projects. This allocation allows both JAS and other projects to extend the PUS services as needed as well as create new ones. JAS services will be reserved across all JAS based projects. Project services may be redefined as needed. Applications should use lookup tables where possible to be as flexible as possible to changing the mapping of service numbers in order to support reuse.