Solutions for route flapping in Ad hoc network based on delay

To alleviate interrupt caused by route flapping, a new protocol AODV-DA, based on AODV, was developed. From three aspects, AODV-DA guaranteed the quality of service in Ad hoc network. Links were built up with delay restriction. Only routes with delay small enough were accepted. If the delay of active route was increasing, AODV-DA would send a route repair message to pre-repair it, before it broke down. AODV-DA chose routes with the smallest average delay, so nodes on this link were averagely reliable. AODV-DA kept all valid routes in its routing table as backup. When active link broke down, AODV-DA shifted to a valid route in its routing table, instead of route re-searching. This saved time cost. By simulating the existing AODV and AODV-DA, the results showed that the latter had a lower drop rate and better performance against route flapping.