The PFTK-model revised

This paper presents an analytical model of TCP Reno throughput as a function of loss event rate, average round trip time, average retransmission timeout value, and receiver window size based on the model proposed by Padhye et al. (widely known as the PFTK-model in correspondence with the initials of the authors). The presented model refines previous work by careful examination of fast retransmit/fast recovery dynamics in the presence of correlated losses and taking into consideration slow start phase after timeout. The accuracy of the proposed model is validated against simulation results and compared with those of the PFTK-model. Simulation results show that the model gives a more accurate estimation of TCP Reno throughput in the presence of correlated losses than the PFTK-model. 2006 Elsevier B.V. All rights reserved.