Power Saving Mechanisms in IEEE 802.11bn protocol ================================================== .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What is the primary goal of power saving mechanisms in 802.11bn?** To extend battery life of devices while maintaining connectivity and network performance in mixed b/n environments. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **How does 802.11bn handle power saving differently than pure 802.11n?** It balances modern power-saving features with legacy 802.11b compatibility, which can add overhead and affect efficiency. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What is Power Save Mode (PSM) in 802.11bn?** Stations enter sleep mode to conserve power and periodically wake to receive buffered frames from the AP. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **How do stations notify the AP when entering or exiting Power Save Mode?** By setting or clearing the Power Management bit in transmitted frame headers. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What is the role of the Traffic Indication Map (TIM) in 802.11bn?** TIM bits in beacon frames inform stations about buffered unicast frames waiting at the AP. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **How does the Delivery Traffic Indication Message (DTIM) function in 802.11bn?** It signals buffered multicast and broadcast traffic, prompting sleeping stations to wake and receive it. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Does 802.11bn support Unscheduled Automatic Power Save Delivery (U-APSD)?** Yes, to improve QoS and reduce latency for power-saving clients. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What is the significance of PS-Poll frames in 802.11bn power saving?** Stations use PS-Poll frames to request delivery of buffered unicast frames from the AP while in sleep mode. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **How do legacy 802.11b devices impact power saving efficiency in 802.11bn networks?** They require protection mechanisms and longer preambles, which increase airtime and reduce power-saving benefits. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Can stations in 802.11bn receive multicast traffic while in power save mode?** Yes, multicast traffic is buffered and sent after DTIM beacons wake sleeping stations. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What is the Listen Interval and how does it affect power saving in 802.11bn?** The number of beacon intervals a station sleeps before waking to check buffered data; longer intervals save more power but increase latency. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **How do APs coordinate power saving with mixed 802.11b and 802.11n clients?** By using protection mechanisms like RTS/CTS and managing buffered frames to minimize interference and power use. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Does frame aggregation in 802.11bn improve power saving?** Yes, by reducing overhead and transmission time, stations can return to sleep faster. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What impact do beacon interval lengths have on power saving in 802.11bn?** Longer beacon intervals allow longer sleep periods but can increase latency for receiving buffered frames. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **How do stations handle missed beacons during power save mode in 802.11bn?** Missing beacons may delay delivery of buffered frames and cause retransmissions, impacting efficiency. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Are power save mechanisms in 802.11bn compatible with MIMO and multiple spatial streams?** Yes, power saving applies across spatial streams with coordination for aggregated frame delivery. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Is special AP support required for U-APSD in 802.11bn?** Yes, APs must support U-APSD to coordinate automatic frame delivery and minimize wake time. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What challenges do legacy 802.11b clients introduce to power saving in 802.11bn?** They increase airtime due to slower rates and protection overhead, reducing overall power saving effectiveness. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **How do power saving mechanisms balance battery life and network performance in 802.11bn?** By scheduling sleep/wake cycles and buffering, devices optimize energy use while maintaining timely data delivery. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow Topics in this section, * :ref:`Reference links ` .. _power_save_step17: .. tab-set:: .. tab-item:: Reference links * Reference links