Resolving poor TCP performance on high-speed long distance links — Overview and comparison of BIC, CUBIC and Hybla

TCP is de facto standard transport protocol. It has been widely adopted and used thanks to the strong guarantees it provides, reliable transmission before all. Today, many applications require fast data transfer over high bandwidth, high latency links. Standard TCP has a huge problem in achieving optimal performance, it substantially underutilizes network bandwidth. Over time, many solutions have been proposed. This paper describes the main problems and circumstances where those arise, especially large Bandwidth-Delay Product links. An overview of modern BIC, CUBIC and Hybla algorithms is provided, and comparative real-world test results and discussion are given.