HYBIC: An Improved Congestion Control Algorithm for Integrated Satellite-Terrestrial Networks in 5G and Beyond Communications

In this paper, we propose an improved Transmission Control Protocol (TCP) algorithm called HYBIC, building upon existing CUBIC and HYBLA algorithms. This HYBIC algorithm is designed for improving capacity utilisation and transmission rate of heterogeneous networks such as the Integrated Satellite-Terrestrial Networks (ISTN) and long delay High Throughput Satellites (HTS) networks on Geostationary Earth Orbit that are characterised with high bandwidth-delay product path. Results analysed indicated that better performance is achieved using the proposed HYBIC algorithm. Considering the results, HYBIC achieved better performance in terms of window growth of 23x10<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> segments, transmission rate of 3Gbps, and capacity utilisation of 60 % compared with both CUBIC and HYBLA. However, the proposed HYBIC inherits the features of Round-Trip Time fairness, scalability, and friendliness of HYBLA and CUBIC algorithms.