A New Real-Time Rate Control Friendly with TCP Hybla over Heterogeneous Networks

In recent years it has been observed in different geographical regions of the world that terrestrial network infrastructure often gets severely affected by big natural disasters. Because of their robustness against disaster, satellite networks or mix of satellite and terrestrial networks are being considered as effective alternatives in such situations. However, satellite links have large propagation delay and also are prone to high link error. A relatively new congestion control scheme, TCP Hybla, has been developed to yield higher network performance in heterogeneous environments incorporating both terrestrial and satellite links. But TCP Hybla behaves aggressively when deployed together with TFRC, a TCP Reno friendly real-time rate control mechanism. As such, TFRC performance deteriorates drastically in the presence of TCP Hybla. In this paper, we propose (i) a new improved analytical model for TCP Hybla and (ii) a novel rate control scheme that we name as TFRC Hybla to overcome the above issue. TFRC Hybla can yield high performance even at the presence of TCP Hybla. Hence it can be effectively used along with TCP Hybla over heterogeneous network environments. Simulations verify the accuracy of our proposed new analytical model for TCP Hybla as well as the effectiveness of TFRC Hybla in such situations.