Reliable and Efficient Multi-rate Aware Routing Protocols for IEEE 802.11 Based MANETs

Abstract

Most existing mobile ad hoc network (MANET) routing protocols use the minimum number of hops as a routing metric. These paths tend to contain long range links that may lower both throughput and reliability. Higher throughput can be achieved by using short but effective links. A few protocols have been proposed to address this issue. The main problem with these protocols is that they use receiver signal strength indicator (RSSI) value to assess the link states. In realistic networks, RSSI value is not always accurate and hence using it can result in inaccurate decisions which will degrade the reliability of paths. Some other unaddressed issues in these protocols include: overhead of periodic hello messages, overhead of relaying data, neglecting paths with same throughput but lesser hops and neglecting changes in link states other than link breakage. We propose two reliable and efficient multi-rate aware routing protocols for MANETs: reliable and efficient multi rate aware proactive (REMAP) routing protocol and reliable and efficient multi rate aware reactive (REMAR) routing protocol. REMAP is a proactive protocol which provides a solution to the other proactive protocols. REMAR is a reactive routing protocol and it solves the problems in other traditional and multi rate aware reactive routing protocols. Both the proposed protocols do not make routing decisions based on RSSI value and hence provide more reliable paths. They also decrease the overhead caused by periodic hello messages in discovering link states of the neighbors and the overhead caused by relaying data. REMAP and REMAR ensure that the path chosen by a node is the fastest path and they update the path whenever a change in link state results in another path being faster than the current one. Simulation results show that our proposed protocols can significantly increase the path reliability and throughput and decrease the network delay and overhead.