TCP over multihop 802.11 networks: issues and performance enhancement

Analyzing TCP operation over 802.11 multihop ad hoc networks involves a cross-layer study. In this work, we investigate the effect of congestion and MAC contention on the interaction between TCP and on-demand ad hoc routing protocol in the 802.11 ad hoc networks. Our study reveals several problems stemming from lack of coordination and sharing in such networks. It is observed that TCP induces the over-reaction of routing protocol and hurts the quality of end-to-end connection. So, one of the critical sources of lowering TCP throughput lies in the TCP window mechanism itself. To fix this problem, we propose a fractional window increment (FeW) scheme for TCP to prevent the over-reaction of the on-demand routing protocol by limiting TCP's aggressiveness. The proposed scheme is applicable to a wide range of transport protocols using the basic TCP mechanism, and the protocol behavior is analytically tractable. Our simulation results demonstrate that the proposed scheme can dramaticall...

• Type: Conference
• Year: 2005
• Where: MOBIHOC
• Authors: Kitae Nahm, Ahmed Helmy, C. C. Jay Kuo
• Keywords: Basic Tcp Mechanism, MOBIHOC 2005, Outperforms Basic Tcp, TCP Window Mechanism, Wireless Networks