802.11bn MAC Timings
What are MAC timing parameters in IEEE 802.11bn?
These define how long devices wait between transmissions, timing for acknowledgments, inter-frame spacing, slot times, backoff, and coordination amongst multiple APs/devices.
Will 802.11bn modify SIFS or other spacings compared to earlier standards?
Yes, expectations are that 802.11bn may introduce tweaks (e.g. shorter or more adaptive SIFS, optimized guard times) for ultra-high reliability and low latency.
How will backoff slot duration behave in 802.11bn?
Likely similar to earlier OFDM-based systems but with optimizations: possibly dynamic slot durations depending on channel conditions or device capability.
What about contention window (CW) sizes in 802.11bn?
CWmin and CWmax will be defined; expected to support rapid expansion and contraction depending on network load, especially in dense deployments.
How will ACK timeout be handled in 802.11bn?
The standard is likely to define tighter ACK timeout windows, accounting for faster PHY and reduced delays.
Is there going to be adaptive inter-frame spaces in 802.11bn?
Yes, possibly adaptive IFS (including SIFS, AIFS, etc.) based on PHY rate, channel conditions, or device class to reduce latency.
How will inter‐frame spacing affect throughput vs reliability tradeoff?
Shorter spacing improves throughput but risks more collisions; 802.11bn aims to balance this via optimized timing and interference-aware designs.
What timing for retransmissions under high error rate scenarios?
Retry intervals might include increased backoff or adjusted spacing to avoid further collisions and maintain reliability.
How will 802.11bn handle timing in multi‐AP coordination?
Coordinated transmission scheduling may require synchronized timing between APs, guard intervals for overlap, and coordination of contention windows.
What is EIFS in 802.11bn and how might it be adjusted?
EIFS would manage extended wait times after errors; 802.11bn may refine its formula (e.g. tighter bounds or adjustable based on MPDU loss stats).
Will beacon interval timing change in 802.11bn?
Potentially yes — for synchronization, faster roaming, and lower latency, beacon intervals may be tunable or shorter where supported.
What is the impact of channel bonding or wider bandwidths on MAC timing?
Wider channels may introduce longer signal detection, processing, or guard intervals; 802.11bn might adjust timings accordingly.
How will timing enforce fairness among legacy and 802.11bn devices?
Through protection modes, careful timing of backoff and contention windows, possibly delay penalties for slower devices.
How are NAV durations handled in 802.11bn timing?
NAV values define virtual busy periods; 802.11bn may include optimizations to limit NAV size, reduce wasted airtime.
What about TXOP timings for multi‐frame transmissions?
TXOP (Transmission Opportunity) durations might be extended, better scheduled, especially when using aggregation or multi-user transmissions.
Are there special timing requirements for ultra-low latency applications?
Yes — 802.11bn aims to support ultra-low latency and high reliability, so timings for control frames, acknowledgments, and retransmissions will be optimized.
How will MAC timing adapt with mobility or device movement?
Movement can introduce delay variations; 802.11bn may include timing allowances or guard intervals to accommodate mobility.
Do timing values depend on PHY features like MIMO, OFDMA or new coding?
Yes, PHY enhancements have impact on MAC delays (encoding/decoding, multi-user scheduling) so MAC timings will be tuned accordingly.
Where can one find the finalized MAC timing values for 802.11bn?
Timing values will be published in the IEEE 802.11bn standard documentation once ratified; in the meantime, draft minutes and contributions from Task Group bn provide proposals. :contentReference[oaicite:0]{index=0}
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