A Stability-Based Overlay Multicast for Mobile Ad Hoc Networks

Stable multicast data delivery structure contributes high data delivery ratio and low control overhead in Mobile Ad Hoc Networks (MANETs). Due to dynamic topology of MANETs, to construct a stable multicast data delivery structure becomes a challenge in ad hoc environment. In this paper, we propose a stable overlay multicast protocol for MANETs based on modified Delayed Forwarding mechanism. In this protocol, each member node precalculates its stability according to remaining battery and local mobility of itself. A source rooted overlay multicast tree is created if source has to send data packets. The overlay creation follows the stability of each member node. By using modified Delayed Forwarding mechanism, a member node with relatively high stability will have highly populated subtrees, by this way to improve multicast routing stability. Data packets are transmitted via IP-in-IP tunnels between member nodes in the overlay tree.