Persistence of routing tables in Wireless Mesh Networks with duty cycling

Currently, clean energy sources, such as solar and wind power, are more and more used in Wireless Mesh Networks (WMNs). Such power sources, however, are intermittent and require these networks to save energy. Duty cycling is a common approach employed by WMNs to save energy by cyclically turning on and off the wireless radios. When the radios are turned off, the node´s routing table eventually expires and, when the radios turn back on, it is necessary to wait for routes to be discovered before sending data. In order to eliminate this need, this work proposes a mechanism to ensure the persistence of the routing tables in wireless mesh networks. PORT (Persistence of Routing Tables) keeps track of routing entries while nodes are in the energy saving mode and thus allows nodes to exchange packets as soon as the radio turns on. Experiments show that PORT increases the route availability and consequently it increases up to 100% the network throughput.