ECTP: An Energy-Efficiency Label-Switching MAC Protocol for Infrastructure Wireless Networks

Recently, the Institute of Electrical and Electronics Engineers (IEEE) 802.11a/b/g Standards have been proposed to support multiple data rates in wireless local area networks. However, even with the capability of transmitting multiple frames with a multirate IEEE 802.11 physical layer (PHY), a mobile host near the fringe of access point's transmission range still needs to adopt a low-level modulation to cope with the low signal-to-noise ratio and thus cannot obtain a data rate as high as that of a host near an access point, in most cases. Taking this into account, in this paper, we study a combined medium-access and next-hop address lookup based on fixed-length labels without the intervention of the host protocol stack. A medium access control protocol, namely the Energy-Efficiency Cut-Through Protocol, is proposed to select a proper PHY mode and a transmission power level that can achieve the maximum energy efficiency. Evaluation results show that, in addition to the increment on throughput, this protocol can provide significant improvements on energy efficiency and remarkably enhance the overall system performance