Performance Evaluation of TCP Congestion Control Algorithms for Wired Networks using NS-3 Simulator

Congestion control and performance analysis of Transmission Control Protocol (TCP) variants have been an open research issue for decades. More and more technologies which require optimal network performances are emerging and it has not been well addressed which existing protocols yield optimum bandwidth. In this paper, we present an evaluation of average throughput and fairness obtained from different combinations of TCP variants for different source algorithms and different variations of router algorithms using an end-to-end and dumbbell topology. In particular we are interested in the quality metrics of TCP Illinois, TCP Vegas and TCP Westwood when selected as the source nodes whereas on the router side we have Controlled Delay (CoDel) and DropTail which implements a packet first-in, first-out (PFIFO) mechanism. In scenarios of both low and high Bandwidth-Delay Product (BDP), the results show that Illinois performs well with both CoDel and droptail in terms of throughput. When considering Jain's fairness, TCP Westwood shared resources more efficiently than the other compared variants.