Increasing ZigBee network lifetime with X-MAC

The ZigBee standard builds on the assumption that infrastructure nodes have a constant power supply. ZigBee therefore does not provide any power-saving mechanisms for routing nodes, which limits the lifetime of a battery-powered ZigBee networks to a few days. This short lifetime drastically restricts the possible application scenarios for ZigBee. To expand the usefulness of ZigBee, we present a ZigBee implementation where we replace the default ZigBee MAC protocol with the power-saving MAC protocol X-MAC. Our results show that X-MAC reduces the power consumption for ZigBee routing nodes with up to 90%, leading to a ten-fold increase in network lifetime at the price of a slight increase in network latency. Furthermore, we are the first to experimentally quantify the energy-efficiency of X-MAC in a multi-hop scenario. Our results indicate that X-MAC reduces the power consumption of idle nodes that are within communication range of two communicating nodes, suggesting that X-MAC may be able to mitigate the hot-spot problem in sensor networks