Space Internetworking Services Area
The Space Internetworking Services Area (SIS) supports the work of the CCSDS by providing services and protocols to address
networked interactions of many forms: - between spacecraft and earth-based resources, - among spacecraft, - between spacecraft and landed
elements, and - within heterogeneous spacecraft. The SIS Area deals with communication services and protocols that are independent of specific
link technology (as a lower layer bound) and independent of application-specific semantics (as an upper bound). This covers essentially the
network through application layers of the OSI reference model. The SIS Area accommodates all ranges of delay, interactivity, and directionality,
although not all protocols are appropriate for all environments.