An experimental evaluation of link delay impact on throughput performance of TCP and SCPS-TP in space communications

Space Communication Protocol Standards - Transport Protocol (SCPS-TP) is a set of extensions to the Transmission Control Protocol (TCP) aimed at improving TCP performance in the space environment. Some work has been done on performance comparison between SCPS-TP and the widely used TCP. It is expected to have an experimental evaluation of the link delay impact on SCPS-TP, especially by comparing it with standard TCP. The paper describes an experimental study of link delay impact on throughput performance of TCP and SCPS-TP. It has been found that the SCPS protocol implementation is less sensitive to link delay variations than the TCP implementation. TCP is highly sensitive, SCPS-VJ is moderately sensitive, and SCPS-Vegas is less sensitive, to the change of link delay.