Performance Evaluation of SSTP A Transport Protocol for Satellite Channels

Most of Internet applications use the transmission control protocol (TCP) at the transport layer network. When Internet communications involve a satellite link, characteristics such as long propagation delay (GEO and MEO satellite links) and high bit error rates affect greatly TCP performance. In this work, we propose a new transport protocol, called SSTP, to be used in a satellite communication. SSTP doesn´t implement any congestion control algorithm, it uses the sliding-window mechanism and ACK segments. Moreover, retransmissions are made based on SACK information and timeout detection in a different manner in order to recover errors more efficiently than TCP. The objective of this paper is to describe and evaluate SSTP performance comparing it to TCP Reno in a simulation scenario. Using the software OPNET Modeler 10.5A, we simulated a data transfer between two ground stations communicating themselves via a GEO satellite link with different values of BER. As performance parameter, we measured the throughput obtained by TCP and SSTP. In all observed cases, SSTP achieved greater performance than TCP.