The IEEE 802.11 Power Saving Mechanism: An Experimental Study

This paper presents an experimental study of the IEEE 802.11 power saving mechanism on PDA in a wireless local area network (WLAN). The power consumptions of the PDA in both continuous active mode (CAM) and power saving mode (PSM) are measured under various traffic scenarios, and the impact of both internal and external factors on power performance, such as beacon/DTIM period and background multicast traffic, are examined. Our findings are: 1) The impact of beacon/DTIM period is only significant when their values are small and the imposed traffic rate is high. 2) The presence of background traffic can significantly reduce the effectiveness of the PSM. Analysis of these findings may provide important guidance to the design of future power saving mechanisms.