SUMMARYEfficient power management is a critical requirement for the battery-operated portable electronic devices incorporating wireless transceivers to have a longer runtime. The existing timer-based power management (TPM) is able to balance energy saving and quality of service requirements by tuning the values of its idle and doze timers. In this paper, the TPM applied in the infrastructure IEEE 802.11 wireless local area network with unreliable wireless links, referred to as TPM-UWL, is presented. A novel stochastic analysis model is developed for TPM-UWL, based on which the probabilities that a mobile station (STA) is at active, dozing, and idle states are obtained. Additionally, the number of buffered frames at the access point and the sleeping STA, the STA's average power consumption, and a frame's average delay under TPM-UWL are derived. Further, the optimization problem that minimizes power consumption under the constraints of delay and buffer size is presented, which enables an STA to set its maximum number of retransmissions and the values of the idle and doze timers in the medium access control layer such that power consumption is minimized, while the constraints of delay and buffer size are satisfied.