TCP congestion avoidance model with congestive loss

This paper presents a model for the TCP congestion avoidance algorithm in networks with only congestive loss. The model predicts the congestion window evolution, throughput and packet loss rate of sustained TCP flows. In other TCP models, packet loss is regarded as exogenous random process. While such assumption is valid in wireless networks, in the wired networks the packet losses are actually the result of network congestion. In this regard, the packet loss rate, the window evolution and throughput of a TCP connection are determined by the bandwidth, delay, buffer size of the underlying network path, the transmitted packet size and number of concurrent TCP flows. We derive formulas to express the TCP congestion window evolution, throughput and packet loss rate as functions of these parameters. The results are verified with simulations and compared with prior works in this area.