S Calable and Robust Location Aware Multicast Algorithm ( Srlama ) for Manet

An ad hoc network is composed of mobile nodes without the intervention of any fixed infrastructure or central administration. Multicasting is intended for group-oriented communication. A lot many applications depend on one-to-many or many-to-many dissemination of the information. However, in ad hoc environment, multicasting protocols are faced with the challenge of producing multihop routes under dynamic topology and bandwidth constraints. Due to the dynamic topology of MANETs it is very difficult to build optimal multicast trees and maintaining group membership, making even more challenging to implement scalable and robust multicast in Mobile Ad hoc Networks (MANET). A Scalable and Robust Location Aware Multicast Algorithm, called SRLAMA, for mobile ad hoc networks is presented in the paper that is based on creation of shared tree using the physical location of the nodes for the multicast sessions. It constructs a shared bi-directional multicast tree with an alternate root that avoids the network partitioning in case of primary root failurte, which results in better performance even than a shared tree. The algorithm uses the concept of small overlapped zones around each node for employing proactive routing with in the smaller zone. Protocol is based on the location information obtained employing relevant data structure, which effectively reduces the overheads for route searching and shared multicast tree maintenance. It employs a preventive route reconfiguration to avoid the latency in case of link breakages and to prevent the network from splitting.