Power Saving Mechanisms in IEEE 802.11w 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 **Does IEEE 802.11w introduce new power saving mechanisms?** No, 802.11w focuses on management frame protection and does not define new power saving mechanisms. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Can IEEE 802.11w be used with existing power saving features?** Yes, 802.11w operates alongside standard power save modes defined in previous 802.11 revisions. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Is Power Save Mode (PSM) supported with 802.11w?** Yes, devices using 802.11w can still enter and exit PSM as defined in legacy 802.11 standards. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Does protected management traffic wake up devices in power save mode?** Yes, if the AP has buffered protected management frames, it can signal the client using TIM/DTIM fields to wake up. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Are multicast/broadcast management frames protected while in PSM?** Yes, 802.11w provides optional protection for broadcast/multicast deauthentication and disassociation frames. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Does power saving affect management frame protection?** Not directly. Frame protection is handled at the MAC layer and is active regardless of power mode. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **What happens if a protected management frame is missed during PSM?** The AP will buffer the frame and notify the station using TIM/DTIM until it wakes and retrieves the data. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Are there any timing constraints for protected frames in power save mode?** Timing constraints are the same as for unprotected frames; buffering and retrieval are handled through standard beacon-based signaling. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Can a device disable management frame protection to save power?** No, 802.11w protection is mandatory once negotiated. Devices must support it without disabling for power reasons. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Does 802.11w affect beacon reception during PSM?** No, devices still wake for beacons as defined by DTIM intervals regardless of frame protection settings. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Can power saving clients support Robust Management Frame (RMF) features?** Yes, as long as they support 802.11w, they can operate in RMF mode and power save mode simultaneously. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Does 802.11w require more power because of encryption?** It may add minor computational overhead, but it does not significantly impact overall power consumption. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Are TIM/DTIM mechanisms changed by 802.11w?** No, TIM/DTIM signaling remains unchanged; it still indicates buffered unicast/multicast frames for sleeping stations. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Does 802.11w work with U-APSD (Unscheduled Automatic Power Save Delivery)?** Yes, 802.11w is compatible with U-APSD used in 802.11e for VoIP and latency-sensitive traffic. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Will protected frames be retried if not acknowledged due to PSM?** Yes, retransmission mechanisms apply to protected frames, just like unprotected ones. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Is sleep duration affected by management frame protection?** No, sleep schedules are managed independently of whether frames are protected or not. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **How does a client in power save mode handle deauthentication frames?** In 802.11w, deauthentication/disassociation frames must be protected and are handled after the client wakes and retrieves them securely. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Can a client reject unprotected management frames while in power save mode?** Yes, if 802.11w is enabled, the client will discard unprotected frames that must be secured under RMF policies. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Do APs need to adjust power saving logic for 802.11w?** Not significantly; they just need to ensure protected frames are queued and signaled appropriately. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow **Is there a risk of denial-of-service if protected frames are not delivered during sleep?** No, since protected management frames are queued and reliably delivered after the client wakes, assuming the AP is compliant. .. panels:: :container: container pb-4 :column: col-lg-12 p-2 :card: shadow Topics in this section, * :ref:`Reference links ` .. _power_save_w_step17: .. tab-set:: .. tab-item:: Reference links * Reference links