ISSN: 1813-0410

Author : Al-Mejibli, Intisar

Improve On-Demand Multicast Routing Protocol in Mobile Ad-Hoc Networks

Intisar Al-Mejibli

journal of kerbala university, Volume 14, Issue 1, Pages 351-363

Ad hoc wireless network is a dynamic reconfigurable wireless network with no dedicated infrastructure, which makes establishing stable route between two mobile nodes difficult task. This attributed to the mobility characteristic in nodes that resulting in changing the network topology frequently. On-Demand Multicast Routing Protocol ODMRP is a common multicast routing protocol designed for wireless ad hoc networks. The dominance of ODMRP comes from its simplicity, high ratio of packet delivery, and independency on a specific unicast protocol. The main rule that ODMRP based on is flooding the entire network with the multicast route request to establish routes of multicast group with forwarding group and to keep the membership of nodes up-to-date. On the other hand, using unicast messages in establishing multicast group is vulnerable to node failures that are common because of the ad hoc networks dynamic nature. This paper proposed an improvement to the available ODMRP which aims to reduce the number of required broadcasting and tackles node failure issue. It’s used unicast messages instead of broadcasting to refresh the nodes membership information which achieved by using ROUTE record with each JOIN REQUEST sent by multicast source. Additionally, it is proposed sending leave message LEAVE MSG by any node intends leaving the multicast group or forwarding group to alert all related nodes to be ready of using alternative route. NS2 simulator is used to apply the suggested improvements. A comparison is conducted between the proposed enhancements and the ODMRP for validation purpose. The obtained results were promising