Space Communications Protocol Specifications

The Space Communications Protocol Specifications (SCPS) are a set of extensions to communications protocols and new communications protocols developed by the Consultative Committee for Space Data Systems (CCSDS) to improve performance of Internet protocols in space environments. The SCPS protocol stack consists of:

• SCPS-FP -- A bit efficient file transfer protocol with advanced features such as record update within a file and integrity checking.
• SCPS-TP -- A set of TCP options and sender-side modifications to improve TCP performance in stressed environments including long delays, high bit error rates, and significant assymetries.
• SCPS-SP -- A security protocol comparable to IPSec
• SCPS-NP -- A bit-efficient network protocol analogous to but not interoperable with IP

The SCPS protocol that has seen the most use commercially is SCPS-TP, usually deployed as a performance enhancing proxy (PEP) to improve TCP performance over satellite links.