Performance of transport protocols over satellite communication links

The Department of Defense (DOD) has joined a cooperative effort with the National Aeronautics and Space Administration (NASA) and the National Security Agency (NSA) to develop the space communications protocol standards (SCPS). The SCPS stack consists of a set of four protocols that operate at the network layer and above: file handling protocol (FP), transport protocol (TP), security protocol (SP), and network protocol (NP). This set of protocols has the potential to increase the efficiency and reliability of data transfer, increase interoperability with both DOD and non-DOD assets, and decrease the cost of operating our space systems. The protocols also have potential applicability to military tactical and mobile communication environments. Two experiments and a number of simulations were conducted in FY96 to evaluate the performance of a subset of the SCPS protocols. This paper summarizes the results of a third test program which was developed in FY97 to further evaluate the performance of SCPS. Although this test program did address functional testing of FP and NP, the focus was on the end-to-end performance of SCPS TP and commercial transmission control protocol (TCP) in networks that include at least one satellite communications link.