MAC protocol for energy efficiency and service differentiation with high goodput in wireless sensor networks

Abstract

In the sensor networks for surveillance, the requirements of providing energy efficiency and service differentiation, which is to deliver high-priority packets preferentially, while maintaining high goodput, which is to deliver many packets within their deadline are increasing. However, previous works have difficulties in satisfying the requirements simultaneously.Previous works on energy conservation have reduced the energy consumption of sensor nodes by using the duty cycle, periodic listen (i.e., turn on radio module) and sleep (i.e. turn off radio module) of sensor nodes. As multiple events, whose priorities are different, occur simultaneously in sensor networks, enhancing goodput and supporting service differentiation are also important. However, the previous works on energy conservation have difficulty in enhancing goodput because of the goodput degradation caused by the duty cycle or retransmissions on each hop. Furthermore, with previous service differentiation methods, varying distributed inter frame space and contention windows size, or using prioritized queueing, it is not easy to support service differentiation and at the same time maintain both enhanced goodput and energy efficiency.

Thus, we propose GES-MAC, which satisfies the requirements simultaneously. GES-MAC reduces idle listening energy consumption by using a duty cycle, periodic listen (i.e., turn on radio module) and sleep (i.e. turn off radio module) of sensor nodes. Cluster-based multi-hop scheduling provides high goodput in a duty-cycled environment by scheduling clusters of nodes in the listen period and opportunistically forwarding data packets in the sleep period. Priority-aware schedule switching makes more high-priority packets reach the sink node by letting high-priority packets preempt the schedules of lowpriority packets. In experiments with MICA2 based sensor nodes and in simulations, the energy consumption of the radio module is reduced by 70% compared to the approaches wit...