A distance-aware counter-based broadcast scheme for wireless ad hoc networks

In mobile ad hoc networks (MANETs), broadcasting is a common operation for providing network functions, such as route discovery and source paging. However, an uncontrolled broadcast, which is also called blind flooding, is inefficient and may lead to heavy redundancies, contentions and collisions, and is commonly referred to as a "broadcast storm" problem. Although this problem has been addressed extensively, most studies suffer with respect to balance between coverage performance and rebroadcasting efficiency. This investigation proposes an efficient algorithm called "DIS-RAD", which introduces the concept of distance into the counter-based broadcast scheme. The proposed approach gives nodes closer to the border a higher rebroadcast probability since they create better expected additional coverage (EAC). Here, a distance threshold is adopted to distinguish between interior and border nodes. Two distinct random assessment delays (RADs) are applied to the border and interior nodes, with the border nodes having shorter RADs than the interior nodes. The analytical results indicate that the proposed scheme indeed provides a higher rebroadcast probability for border nodes and a lower rebroadcast probability for interior nodes. The simulation results demonstrate that the proposed "DIS/spl I.bar/RAD" scheme works much better than other schemes. The probability analysis model also confirms the validity of the simulation results. Most important, the proposed scheme can keep good balance between reachability and rebroadcast efficiency in various network densities. Therefore, the dynamic adjust counter threshold according to network densities is not necessary.