Performance analysis of modern TCP variants: A comparison of Cubic, Compound and New Reno

Abstract

TCP is the main and most widely used transport protocol for reliable communication. Because of its widespread need, researchers have been studying and proposing new TCP variants trying to improve its behavior towards congestion to make it use the most available bandwidth while preserving a logical level of fairness towards other protocols. This paper aims at evaluating and comparing the performance of the most recent TCP implementations deployed in popular Operating Systems. We carefully choose scenarios to investigate the goodput, intra- and inter-protocol fairness of these TCP variants. Results show that running Cubic over wired links outperforms Compound and New Reno in the presence of reverse traffic. However, the protocols behave differently over wireless links where they achieve a low goodput with a very small variation. Also, all three variants are fair to other TCP traffic and achieve the same intra-protocol fairness over wireless links.