Networking protocols for space data communications

Space communications organizations, both civil and military, have focused their attention primarily on the physical (layer 1) and data link (layer 2) layers of the Open Systems Interconnection (OSI) reference model. The need to reduce space operations costs, the expected availability of distributed communications architectures within space vehicles, and the design of increasingly complex space constellations have generated civil and military requirements to provide functions such as end-to-end networking, data protection, reliable delivery and file handling. Under a joint technical effort by the US Department of Defense (DoD) and the National Aeronautics and Space Administration (NASA), space data communications protocols are being developed to provide these functions. The capabilities needed to be provided in these protocols are very much influenced by space communications constraints in areas such as computing resources, data rates, contact time, delay and transmission errors. These new space protocols have been submitted to both the US government and the Consultative Committee for Space Data Systems (CCSDS) for approval as standards. The commercial space, military tactical, and wireless personal communications communities, which have system and environment constraints similar to those encountered in space data communications, may also benefit from the technology of these space protocols.