New explicit loss notification for TCP in wireless networks

To alleviate the performance degradation of conventional TCP in wireless networks, we propose a new explicit loss notification (ELN) scheme. By monitoring the operation of a link layer, the proposed scheme can rapidly and accurately differentiate the errors in wireless links or the errors due to channel contention in multiple access from the errors of network-layer congestion. When a wireless link error is detected, a base station (BS), an access point (AP) for down link connections or a mobile node for an uplink connection notifies the TCP sender to avoid unnecessarily shrinking its congestion window. Furthermore, to alleviate successive shrinking of a congestion window due to inherent multiple packet drops in the previous ELN schemes, we propose a new packet list for the TCP sender. We show that the proposed scheme can reduce the size of the list significantly. Finally, we demonstrate that by combining the new ELN scheme with the proposed packet list, data throughput can be enhanced over existing protocols.