Network coding in duty-cycled sensor networks

Network coding and duty-cycling are two popular techniques for saving energy in wireless adhoc and sensor networks. To the best of our knowledge, the idea to combine these two techniques, for more aggressive energy savings, has not been explored. One explanation is that these techniques achieve energy efficiency through conflicting means, e.g., network coding saves energy by exploiting overhearing, whereas duty-cycling saves energy by cutting idle listening and, thus, overhearing. In this paper, we evaluate the use of network coding in duty-cycled sensor networks. We propose a scheme, called DutyCode, in which a MAC protocol implements packet streaming and allows the application to decide when a node can sleep. We investigate our scheme analytically and implement it on mote hardware. We evaluate our solution in a 42-node indoor testbed. Performance evaluation results shows that our scheme saves 20-30% more energy than solutions that use network coding, but do not use duty-cycling.