Reliable optimised flooding in ad hoc networks

Information dissemination (flooding) forms an integral part of routing protocols, network management, service discovery and information collection (sensing). Given the broadcast nature of ad hoc network communications, information dissemination provides a challenging problem. Blind flooding in ad hoc networks results in the broadcast storm problem. To limit the broadcast storm problem, mechanisms for optimised flooding have been proposed. However, this optimisation reduces the inherent level of redundancy. the minimum spanning tree (MST) algorithm using local one hop topology in a distributed manner as the basis of a more reliable optimised flooding mechanism called, reliable minimum spanning tree (RMST) flood is proposed. RMST utilises unique properties of MST graphs that allow for broadcast transmissions to be replaced by unicast transmissions. Unicast transmission is inherently more reliable than broadcast transmission as it utilises link layer acknowledgement and retransmission, thereby improving the reliability of a flood and reducing the broadcast storm problem. Simulation is used to show that RMST is able to achieve equivalent reliability in terms of packet delivery compared to blind flooding. Importantly, RMST is able to achieve significantly better performance than MPR and equivalent performance to LMSTFlood in terms of reducing the broadcast storm problem.