Mobility tolerant maintenance of multi-cast tree in mobile multi-hop radio networks

Abstract

When the nodes in a mobile ad hoc network move, existing links often no longer exist and/or new links are created. Any communication protocol designed for such multi-hop ad hoc networks must be able to tolerate such change in network topology that can occur anywhere in the network. Another characteristics of such networks is that bandwidth is a comparatively precious resource and needs to be conserved. Our purpose in the present paper is to explore the possibilities of applying the relatively new paradigm of self-stabilization in distributed fault tolerant algorithm design to tackle the problem of topology change in mobile networks. Self-stabilizing distributed algorithms converge to a global legitimate state in presence of any number of intermittent faults and still use only local knowledge for actions at each node. Our objective is to view the topology change as a change in the node adjacency information at one or more nodes and utilize the tools of self-stabilization to converge to a stable global state in the new network graph. We illustrate the concept by designing a new efficient distributed algorithm for multi-cast in a mobile network that can accommodate any change in the network topology due to node mobility.