A Mobile Multicast Routing Mechanism based on the Comparison of Tree Reconstruction Cost and Tunneling Cost

Mobile multicast schemes are classified into remote subscription and bi-directional tunneling. While the former scheme has much overhead in the maintenances of multicast tree, the latter suffers from inefficient routing. In this paper, we propose dynamic mobile multicast routing (DMMR) scheme, which is operated on the basis of cost functions related with forwarding cost and tree reconstruction cost, Basically DMMR intends to find lower cost between forwarding cost and tree reconstruction cost. Forwarding cost is the cost of tunneling multicast packets from home agent, and tree reconstruction cost is the joining cost of foreign agent to multicast group. In the case that a mobile host moves to the other area, its foreign agent calculates cost functions related with forwarding cost and tree reconstruction cost. If forwarding cost is higher than tree reconstruction cost, foreign agent joins to multicast group and reconstructs the multicast tree. Accordingly, foreign agent can dynamically adapt remote subscription or bi-directional tunneling, Our scheme provides more stable multicast service to the mobile hosts regardless of the movements of mobile host and the number of mobile group members.