Thread Links Date Links
Thread Prev Thread Next Thread Index Date Prev Date Next Date Index

Re: [STDS-802-11-TGBN] LB291 CR for NPCA Initial Channel Access

Dear all,

 

I have uploaded 11-25/2196r5 (8 CIDs) to mentor.

https://mentor.ieee.org/802.11/dcn/25/11-25-2196-05-00bn-lb291-cr-for-npca-initial-channel-access.docx

 

During the last presentation, several members expressed concerns that the proposed synchronization resolution lacks technical motivation. In response, this revision adds simulation results for multiple scenarios quantifying the performance impact of synchronized vs. unsynchronized initial channel access on the NPCA primary channel.

 

For your convenience, here are a few examples from the simulation results:

  • Collision probability increases significantly when unsynchronized channel access is used. For example, the collision probability for 2 non-AP STAs with AC_VO traffic when synchronized channel access is used is 24.8% compared to a staggering 65.3% when unsynchronized channel access is used.
  • Unsynchronized access acts as an AIFSN equalizer. The QoS advantage of a shorter AIFSN is mitigated when the backoff expires and while the designated recipient has not completed switching, leading to a new backoff draw. For example, the probability that a non-AP STA with AC_VO traffic wins the initial channel access in the presence of 10 non-AP STAs with AC_BE traffic when synchronized channel access is used is 48.1% compared to 34.2% when unsynchronized channel access is used.
  • Fast-switching non-AP STAs cause downlink starvation when associated with a slow-switching AP. For example, the probability that an AP with AC_BE traffic wins the initial channel access in the presence of 6 non-AP STAs with AC_BE traffic is a mere 2.1% when unsynchronized channel access is used and the AP switching delay is 40us and the non-AP STAs switching delay is 4us.
  • Fast-switching non-AP STAs increase downlink latency when associated with a slow-switching AP. For example, the probability that an AP with AC_VO traffic wins the initial channel access in the presence of 6 non-AP STAs with AC_BE traffic when synchronized channel access is used is 78.2% compared to 23.3% when unsynchronized channel access is used and the AP switching delay is 40us and the non-AP STAs switching delay is 4us.

 

In summary, the results demonstrate that without a common synchronization point, the fundamental fairness and priority mechanisms of 802.11 are compromised, significantly reducing the intended gains of NPCA.

 

I look forward to your comments.

 

Best regards,

Rony

 

 

 

From: Rony Ross <0000491f5321510d-dmarc-request@xxxxxxxxxxxxxxxxx>
Sent: Thursday, February 5, 2026 3:32 PM
To: STDS-802-11-TGBN@xxxxxxxxxxxxxxxxx
Subject: Re: [STDS-802-11-TGBN] LB291 CR for NPCA Initial Channel Access

 

Dear all,

 

I’ve uploaded 11-25/2196r4 (8 CIDs) on mentor. It includes refinement to one of the EDCAF conditions.

https://mentor.ieee.org/802.11/dcn/25/11-25-2196-04-00bn-lb291-cr-for-npca-initial-channel-access.docx

 

Your comments are welcome.

 

Best regards,

Rony

 

 

From: Rony Ross
Sent: Tuesday, February 3, 2026 2:57 PM
To: STDS-802-11-TGBN@xxxxxxxxxxxxxxxxx
Subject: RE: LB291 CR for NPCA Initial Channel Access

 

Dear all,

 

I’ve uploaded 11-25/2196r3 (8 CIDs) on mentor. The main changes are:

  • 4 CIDs related to transmission deferral were moved to a new document 11-26/271
  • Establishing a common refence point is based on the NPCA switch delay of the AP instead of using a new “NPCA Switch Guard Time” field.

https://mentor.ieee.org/802.11/dcn/25/11-25-2196-03-00bn-lb291-cr-for-npca-initial-channel-access.docx

 

Your comments are welcome.

 

Best regards,

Rony

 

 

From: Rony Ross <0000491f5321510d-dmarc-request@xxxxxxxxxxxxxxxxx>
Sent: Friday, January 9, 2026 3:52 AM
To: STDS-802-11-TGBN@xxxxxxxxxxxxxxxxx
Subject: Re: [STDS-802-11-TGBN] LB291 CR for NPCA Initial Channel Access

 

Dear all,

 

I've uploaded 11-25/2196r2 on mentor. It includes changes following comments and discussions and 3 more CIDs.

https://mentor.ieee.org/802.11/dcn/25/11-25-2196-02-00bn-lb291-cr-for-npca-initial-channel-access.docx

 

Your comments are welcome.

 

 

Best regards,

 

Rony

 

 

From: Rony Ross
Sent: Monday, January 5, 2026 3:18 PM
To: STDS-802-11-TGBN@xxxxxxxxxxxxxxxxx
Subject: RE: LB291 CR for NPCA Initial Channel Access

 

Dear all,

 

I’ve uploaded 11-25/2196r1 on mentor, addressing comments received offline.

https://mentor.ieee.org/802.11/dcn/25/11-25-2196-01-00bn-lb291-cr-for-npca-initial-channel-access.docx

 

Your comments are welcome.

 

Best regards,

Rony

 

From: Rony Ross
Sent: Monday, December 8, 2025 4:09 PM
To: STDS-802-11-TGBN@xxxxxxxxxxxxxxxxx
Subject: LB291 CR for NPCA Initial Channel Access

 

Dear NPCA TTT members,

 

I have uploaded the following NPCA CRD that addresses the initial channel access on the NPCA primary channel.

Please review and let me know if you have any feedback.

 

11-25/2196 - LB291 CR for NPCA Initial Channel Access

 

Thanks,

Rony

To unsubscribe from the STDS-802-11-TGBN list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=STDS-802-11-TGBN&A=1

To unsubscribe from the STDS-802-11-TGBN list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=STDS-802-11-TGBN&A=1

To unsubscribe from the STDS-802-11-TGBN list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=STDS-802-11-TGBN&A=1