Survey on Wireless link Reliability Mechanisms using Transmission Control Protocol

Wireless Communication, one of the important demanding technologies basically suffers from unreliable nature due to its high bit error rate caused by handoffs. Transmission Control Protocol, the reliable successful Transport Protocol, basically designed for a wired network handles network congestion effectively. When TCP is implemented over Wireless Network, there will be significant loss due to the unreliable nature of wireless link rather than by congestion. But, TCP implicitly assumes the loss is due to congestion and reacts by invoking congestion control algorithm which degrades throughput, delay, packet discard ratio; finally ending up with inefficient utilization of bandwidth. There are two approaches to handle the situation, either hide the non-congestion losses from TCP sender or differentiate the non-congestion losses from congestion losses. The mechanisms proposed based on the two approaches can be classified into three groups (1) End-to-end protocol, (2) Split Connection protocol, and (3) Link Layer protocol. These schemes are compared and surveyed based on the metrics affecting both Wireless Network and TCP, and a comprehensive report is generated in this survey paper.