Cross-Layer Hop-by-hop Congestion Control in Mobile Ad Hoc Networks
The poor performance of TCP in wireless networks is further diminished in IEEE 802.11-based ad hoc networks due to the unnecessary actions of on-demand routing protocols when interference-induced packet drops occur at the Medium Access Control (MAC) layer. In this paper, the authors present a cross-layer hop-by-hop congestion control scheme designed to improve TCP performance. The proposed scheme attempts to determine the actual cause of a packet loss and then coordinates the appropriate congestion-control response among the MAC, network, and transport protocols. The congestion control efforts are invoke at all intermediate and source nodes along the upstream paths directed from the wireless link experiencing the congestion-induced packet drop.