Variable update period for DSDV protocol

DSDV is a Distance-Vector routing protocol, which demands that every node periodically broadcast updated information. After analyzing the character and recent research on DSDV, the paper proposes a variable update cycle algorithm for DSDV to solve the problem that the cost and bandwidth waste largely increase because of broadcast updating when a increasing number of nodes enter the Ad Hoc. It sets different update cycle according to different node and the whole circumstance of Ad Hoc network. In order to cut down unnecessary resource waste, the algorithm mainly takes into account the remnant battery power in the node and the rate of topology change. The simulation results indicate that improved DSDV can evidently reduce bandwidth waste and prolong life-span of the nodes.