Multi sample retransmission timeout (RTO) approximation for multi-hop wireless networks

Abstract

Transmission control protocol (TCP) performance under multi-hop wireless network heavily depends on retransmission timeout (RTO) estimation algorithm. The existing Jacobson RTO estimation algorithm implemented in the TCP's retransmission (RT) timer collapses under multi-hop wireless environment due to sudden round trip time (RTT) delay spike, leads to the spurious timeout. This paper proposes an enhanced RTO estimation algorithm known as multi-hop RTO (MRTO) intended for the multi-hop wireless environment. The MRTO estimation algorithm computes spike suppression value of the recently received M RTT samples that withstand against the sudden delay spike impact. The simulation results prove that proposed MRTO yields a substantial estimation error and spurious RTO timeout reduction against the Jacobson's RTO estimate and Cauchy Round Trip Time Predictor (CRTTP) under multi-hop wireless network.