Most existing on-demand mobile ad hoc network routing protocols continue using a route until a link breaks. During the route reconstruction, packets can be dropped, which may cause significant throughput degradation. In this paper, we add a link breakage prediction algorithm to the Dynamic Source Routing (DSR) protocol. The mobile node uses signal power strength from the received packets to predict the link breakage time, and sends a warning to the source node of the packet if the link is soon-to-be-broken. The source node can perform a pro-active route rebuild to avoid disconnection. Experiments demonstrate that adding link breakage prediction to DSR can significantly reduce the total number of dropped data packets (by at least 20%). The tradeoff is an increase in the number of control messages by at most 33.5%. We also found that the pro-active route maintenance does not cause significant changes in average packet latency and average route length.
['Liang Qin', 'Thomas Kunz']
Pro-active route maintenance in DSR