The impact of path-delay routing on TCP in ad hoc networks
Despina Triantafyllidou, Khaldoun Al Agha · 2009
In the present work we examine the impact of average path-delay routing (APDR) to TCP, in 802.11 ad hoc networks. The route discovery is based on the lowest average-delay path, and on optimised link state routing (OLSR). The simulation study on ad hoc scenarios reveals an improved roundtrip time (RTT) for TCP, but a reduced throughput. As shown, regular route oscillation events cause packet reordering. Thus, only the delay as a routing metric is not sufficient to improve TCP. We apply an APDR optimisation, i.e., a path reservation scheme, in order to avoid route oscillations in static ad hoc networks. Thus, APDR outperforms standard OLSR and improves the TCP throughput. The results of the present study yield for a descent controling algorithm, to avoid the multi-path effect.