Abstract: Quality-driven video delivery is the key to ensure the quality of service for video transmission over IEEE 802.11 WLAN. The goals of traditional communication technology are to reducing packet loss, increasing throughput, and so on. However, the feature of video flows and experience of users fail to considerate in these targets. The enhancements for QoS support being defined in the IEEE 802.11 standard draft were introduced first. The state-of-the-art scheduling algorithms based on polling and based on contention were described in detail.