When a wireless link forms a part of a network, the rate of packet loss due to link noise may be considerably higher than observed in a modern terrestrial network. This paper studies TCP performance over a range of link environments and highlights the advantage of recent modifications to TCP (e.g. SACK, New-Reno) for wireless communications. It also identifies two key issues which impact the performance of TCP over error prone links: TCP’s reliance on timers to recover from a failed retransmission cycle, and TCP’s inability to separate congestion packet loss from other types of packet loss. A solution to the first issue is identified and analysed by simulation, and the factors affecting the second issue are outlined.
Nihal K. G. Samaraweera, Godred Fairhurst