Stateless Broadcasting to support Heterogeneous Radio Ranges in Mobile Ad Hoc Networks

A MANET (mobile ad hoc network) requires an efficient network-wide broadcasting service in route discovery as well as in many applications. Recently, many broadcasting protocols have been proposed to avoid the well-known broadcast-storm problem, or to provide reliability over wireless broadcast media. However, since it is assumed that all nodes in the network have the same radio ranges (i.e. homogeneous radio ranges), the protocols do not work in a realistic environment where all nodes have different fixed radio ranges or they use dynamic radio ranges intentionally to save their energy in the network (i.e. heterogeneous radio ranges). We therefore propose an efficient stateless broadcasting technique to support the heterogeneous radio ranges. An additional area covered through a node's rebroadcasting is calculated by considering different radio ranges of nodes. Then, nodes with larger coverage area will rebroadcast earlier than other nodes with smaller area. When determining rebroadcasting schedule, the DFD (dynamic forwarding delay) concept introduced in DDB (dynamic delayed broadcasting) is exploited in our protocol. Extensive simulation using ns-2 proves that our scheme is more suitable for a realistic environment.