Abstract: This study analyses the issue of reliability and to propose a scalable method to improve packet delivery of multicast routing protocols and also to reduce the variation in the number of packets received by different nodes. Multicast protocols that have been proposed provide no reliability guarantee and not suitable when the network topology undergoes frequent changes. Gossip technique has been proposed to construct scalable and reliable multicast protocols. Gossip is well matched to the needs of adhoc networks because it is a controlled form of flooding, propagating the messages without congesting the wireless medium and is independent of topology. So the anonymous gossip technique can be implemented on any of the existing multicast routing protocol in order to improve the reliability and scalability. The proposed work implements the anonymous gossip over the multicast routing protocol ODMRP. The implementation consists of two phases. In the first phase, On Demand Multicast Routing Protocol (ODMRP) is used to multicast a message to the group member, while in the second phase the gossip protocol tries to recover lost messages. When a group member, the group member checks information in the message to detect if it is missing some messages, receives a gossip message. A retransmission request for missing messages is sent directly to the gossip message sender called as gossip push. An alternate technique is gossip-pull method, wherein a gossip sender informs all members of its gossip subgroup about all messages it is missing. Members of a gossip subgroup of a group member can be chosen at random, or from the neighborhood of the group member. This study shows that the packet delivery of ODMRP has been significantly improved. Also the variation in number of packets delivered is decreased .The performance is also analyzed by means of varying the performance metrics.
P. Latha and R. Ramachandran , 2006. Implementation of Gossip on ODMRP for Wireless Ad-hoc Network. Asian Journal of Information Technology, 5: 877-883.