Power Saving Mechanisms in IEEE 802.11w protocol
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.
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.
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.
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.
Are multicast/broadcast management frames protected while in PSM?
Yes, 802.11w provides optional protection for broadcast/multicast deauthentication and disassociation frames.
Does power saving affect management frame protection?
Not directly. Frame protection is handled at the MAC layer and is active regardless of power mode.
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.
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.
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.
Does 802.11w affect beacon reception during PSM?
No, devices still wake for beacons as defined by DTIM intervals regardless of frame protection settings.
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.
Does 802.11w require more power because of encryption?
It may add minor computational overhead, but it does not significantly impact overall power consumption.
Are TIM/DTIM mechanisms changed by 802.11w?
No, TIM/DTIM signaling remains unchanged; it still indicates buffered unicast/multicast frames for sleeping stations.
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.
Will protected frames be retried if not acknowledged due to PSM?
Yes, retransmission mechanisms apply to protected frames, just like unprotected ones.
Is sleep duration affected by management frame protection?
No, sleep schedules are managed independently of whether frames are protected or not.
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.
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.
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.
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.
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