Comparative performance evaluation of TCP Hybla and TCP Cubic for satellite communication under low error conditions

Satellite communication has become important in the current global data communication due to its large coverage area. Satellite links are affected by two major concerns: long propagation delays, and relatively high error rates. Standard TCP congestion control variants were not designed to address these challenges. They generally depend on round trip times (RTTs), and hence suffer heavily if the RTTs are large. Various TCP variants like Hybla have been proposed in order to optimize the channel throughput in heterogeneous networks incorporating satellite links. The error rate of satellite channels can be substantially mitigated using forward error correction (FEC) techniques. In such a situation, according to the results obtained by our comparative study, the performance of Cubic, which is designed for high-speed networks, is better than Hybla, in conditions of high-latency and low error rates.