An efficient multicast routing protocol to minimize multipoint relays in MANET.

Abstract

Reducing control packets, especially in proactive routing protocols, needed to establish routes can lower network overhead in Mobile Ad-hoc Networks (MANETs). Optimized Link State Routing (OLSR) is a proactive routing protocol renowned for its widespread culmination in MANET. In OLSR, each Multi-point Relay (MPR) node propagates Topology Control (TC) messages across the network to advertise neighbor information. The number of MPR nodes and hence TC messages are significant contributors to increased network overhead; however, OLSR counteracts or controls the TC messages by reducing the number of MPR nodes. In this study, we propose an efficient MPR node selection mechanism to reduce the TC message volume leading to a minimized routing overhead. Each node selects the lowest cost node from its first hop neighbors as the MPR node for any destination. The same MPR node can be selected for multiple destinations if it costs the lowest for each destination node. The selection technique is realized by modifying only the default OLSR TC and Hello messages. The proof-of-concept implementation in the NS3 simulator reveals that the proposed methodology reduces the routing overhead by selecting around 55%, 28% and 49% (on average) fewer MPR nodes compared to the traditional OLSR, SSTB and M-OLSR protocol respectively, without negotiating packet delivery ratio, throughput and delay