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

Re: [STDS-802-11-TGBN] Soliciting comments on group addressed BU delivery for PUO STAs



Dear all,

 

I just presented CR document with group addressed BU delivery for PUO STAs: https://mentor.ieee.org/802.11/dcn/26/11-26-0031-02-00bn-lb291-cr-for-miscellaneous-cids.docx

 

I received several comments and questions during the presentation and would like to open a discussion. Based on our discussion, I intend to modify the CR document accordingly.

 

**Comment 1: No changes in AP’s behavior.**

 

I would like to highlight a key distinction between PUO and traditional power save or P2P operation. With PUO, there is no guarantee that the DTIM beacon will not overlap with a STA's PUO unavailable time. The same issue applies to DUO STAs as well. While this is not a straightforward problem to resolve, leaving it unaddressed means PUO/DUO STAs may occasionally miss DTIM beacons and the delivery of group addressed BUs.

 

**Comment 2: The AP shall buffer group addressed BUs for PUO STAs.**

 

I generally agree with this statement; however, there may be corner cases worth considering. For example, if there are no other power save STAs in the BSS — only a PUO STA — and the AP knows that the PUO STA's unavailable time overlaps with the next DTIM beacon, should the AP still buffer the group addressed BU?

 

**Comment 3: Buffered frames may be time sensitive.**

I agree with this comment — timely delivery of buffered frames is important. Therefore, we have added a recommendation for PUO STAs to listen for the DTIM beacon and the subsequent group addressed frame delivery. "PUO non-AP STAs should follow the rules defined in 11.2.3.7 (Receive operation for STAs in PS mode) for DTIM beacons and group addressed MPDUs delivery. (#5099)"

 

Please note that all changes in my CR are recommendations, intended to leave APs and non-AP STAs some flexibility in handling corner cases.

 

Best regards,

 

Hanqing

 


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