A Stability-Oriented 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 the 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 stability-oriented overlay multicast protocol for MANETs based on a modified Delayed Forwarding mechanism. In this protocol, each member node precalculates its stability according to residual battery and its local mobility. A source rooted overlay multicast tree is created if source has to send data packets. The overlay construction follows the stability of each member node. By using a modified Delayed Forwarding mechanism, a member node with relatively high stability will have highly populated subtrees, SOOMP improves multicast routing stability by trying to push the unstable member nodes to the edge of the multicast tree. Data packets are transmitted via IP-in-IP tunnels between member nodes in the overlay tree.