“A survey on TCP CUBIC variant regarding performance”

CUBIC is one of the most popular version of TCP being used by many flavours of Linux now a days. CUBIC [6] is an enhanced version of BIC TCP (Binary Increase Congestion Transmission Control Protocol) ??. To enhance the scalability of TCP in long distance network scenarios, CUBIC modified the linear window growth function of standard TCP to cubic [6] function. During communication, CUBIC decreases the size of congestion windows (cwnd) at Saturation-States and increases its size instantly at Stable-States. CUBIC protocol keeps the window-increase- rate independent of RTT, which helps the protocol TCP friendly in short and long RTTs. When the CUBIC window-growth-function is slower than standard TCP, CUBIC [6] behaves like standard TCP in order to provide fairness to standard TCP. In this Paper, CUBIC performance evaluation is done by Network Simulator-2 experiments. As this is a survey paper, performance analysis of other TCP versions is also discussed.