An energy-efficient architecture of low duty cycle for opportunistic networks

Abstract

In the opportunistic networks, many researchers apply the sleep scheduling policy to save energy, which can allow mobile nodes sleep or wake up periodically. However, when the nodes are in a cyclical sleeping mode, they will miss some effective contacts with other nodes. This situation will inevitably increase the inter-contact time, affect the message delivery probability, and increase message delay time. It is almost impossible to find an optimal energy strategy which can maximize the energy saving and message delivery probability meanwhile minimizing the delay time of the message. We consider that it is important to make a trade-off among energy saving, message delay and message delivery probability. In this paper, we first calculate a reasonable duty cycling under the condition of giving tolerated message delay and message delivery probability. We take advantage of the derived duty cycling and propose an energy-efficient architecture of low duty cycle named EEALDC. Through theoretical analysis and experimental simulation, we demonstrate that EEALDC can save the energy of nodes and extend the lifetime of the opportunistic networks in the situation of constraining energy, message delay time and message delivery probability.