802.11u MAC Timings
What MAC timing parameters are important in IEEE 802.11u?
Key timings include SIFS, DIFS, EIFS, and backoff intervals used for medium access and collision avoidance.
Does 802.11u introduce any new MAC timing parameters?
No new timing parameters are introduced, but additional management frame exchanges can impact overall timing.
How do MAC timings affect pre-association query exchanges in 802.11u?
Pre-association queries use the Generic Advertisement Service (GAS), which must fit within existing timing constraints to avoid delays.
Is the SIFS interval the same in 802.11u as in other 802.11 standards?
Yes, SIFS remains consistent to maintain interoperability and timing for ACKs and responses.
How does 802.11u handle timing for authentication and association frames?
These frames follow standard MAC timing rules but may include additional elements, so devices need to handle slightly longer frame processing.
Do GAS exchanges increase channel occupation time?
Yes, GAS query and response frames add extra exchanges which may increase channel occupancy and affect timing.
Are contention window and backoff algorithms affected by 802.11u?
No fundamental changes, but the increased frame exchanges may indirectly affect medium access timing.
Does 802.11u require changes to slot times for channel access?
No, slot times remain consistent with previous 802.11 standards to ensure compatibility.
How does 802.11u impact timing for power save mode?
By reducing unnecessary scanning through better network info exchange, 802.11u can help optimize power save wake/sleep cycles.
Are retransmission timers affected by 802.11u?
Retransmission timers stay the same, but additional management frame traffic may increase the need for retransmissions.
Does 802.11u affect the timing of beacon frames?
Beacon intervals generally remain unchanged, but beacons may include additional information elements related to interworking.
How do timing constraints affect emergency alert transmissions in 802.11u?
Emergency alerts must comply with strict timing to ensure timely delivery, leveraging existing MAC timing parameters.
Does 802.11u timing impact roaming latency?
It aims to reduce roaming latency by allowing faster network discovery and selection before association, optimizing timing sequences.
Are there any timing requirements for transmitting ANQP messages?
ANQP messages are carried in GAS frames, which must comply with standard MAC timing rules to avoid collisions.
Can 802.11u MAC timing adjustments improve QoS?
Indirectly, yes—by enabling faster network selection and association, it supports more reliable QoS delivery.
How are timing conflicts minimized during multiple network queries in 802.11u?
Devices manage GAS exchanges carefully within contention windows to avoid excessive channel occupation.
Does 802.11u timing support fast BSS transitions?
While fast BSS transition (802.11r) is separate, 802.11u’s improved pre-association info can complement faster transitions.
How does 802.11u timing influence multi-AP coordination?
Timing remains governed by standard MAC protocols, but additional interworking info aids better AP coordination.
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