| Thread Links | Date Links | ||||
|---|---|---|---|---|---|
| Thread Prev | Thread Next | Thread Index | Date Prev | Date Next | Date Index |
Thomas Derham • q
[V] Abhishek Patil (Qualcomm Technologies, Inc) • q
[V] Pooya Monajemi, Apple • q
[V] Zhenpeng Shi, Huawei • q
[V] Liwen Chu, NXP • q
[V] Reza Hedayat, Apple • q
[V] Abhishek Patil (Qualcomm Technologies, Inc) • Curious question based on what you (Binita) answered (to Thomas) - what do you mean by PHY generation changing? The Beacons and other mgmt frames are still sent in legacy format. And a legacy device is expected to ignore the new IEs that it doesn't understand.
<BG> What I mean is that the BSSID is changed from being an 11be BSSID to an 11bn BSSID or even vice versa (if for some reason a BSSID needs to be downgraded because of issues seen after an upgrade). Changing PHY gen (up or down) would reset the BSSID, which would disconnect clients.
[V] Ming Gan Huawei • also confused about this PHY change. Should MBSSID have the same hardware? software update?
<BG> Let me try to explain how an AP device upgrade works. Assume a Wi-Fi 7 AP device needs to be upgraded to Wi-Fi 8. As you rightly say that this involves HW upgrade (called a HW refresh) + upgrade to new software on the new AP HW. Once the new AP hardware is installed, the BSSIDs are typically started still as older generation. In this case, after the AP HW refresh to Wi-Fi8, the BSSDIs in the MBSSID Set will still start as Wi-FI 7. So, the AP device has new HW and new software, but OTA BSSIDs (SSIDs) are still configured as Wi-Fi7 (meaning they are advertising beacon, probe resp etc of Wi-Fi7). Then customers will observe that there are no issues for some time with the new HW/SW keeping the SSIDs as WI-Fi7. Then customer can start phased upgrade of BSSIDs (SSIDs) to Wi-Fi8. They will typically start with upgrading a nonTx BSSID to Wi-FI8. This is now changing the PHY gen of that BSSID from 11be to 11bn and will require reset of that BSSID, and today because that BSSID now has to be moved out to a different 11bn MBSSID set, it will restart all the BSSIDs in the 11be MBSSID set and this new BSSID.
Then customer will observe for some time to make sure there are no issues. If any issues, they will revert back the BSSID to Wi-Fi7, which will again require BSSID to be moved to the previous MBSSID gset that will cause reset of all the BSSIDs in that set (causing a big blast radius of BSSIDs that are reset).
Ming: could we have a temporal AP to maintain the connectivity during the update phase
<BG> STAs can be BTM'd to another AP for the BSSID being upgraded, but due to the MBSSID regrouping that happens today, many more BSSIDs get reset, which must be avoided. We want to minimize the blast radius when a BSSID upgrade happens.
[V] Pooya Monajemi, Apple • that's actually the only way to solve it. otherwise there are disruptions due to hardware change, own VAP upgrade, and Tx-BSSID upgrade
<BG> HW refresh of an AP device is carefully scheduled to minimize downtime and done in a rolling manner across APs in a physical space, so there are APs to continue to provide connectivity. When a BSSID is reset, then those STAs will get disconnected and reassociate - impact radius would be limited to that BSSID only or if Tx BSSID upgrade, then to VAPs in that MBSSID.
Goal is to limit the impact radius and not have BSSIDs in multiple MBSSI sets get reset.
Thomas Derham • It sounds like a single BSS in the set is being software updated so it will start advertising new (e.g. UHR) IEs, and the STAs in that BSS will need to disconnect, but the objective is that the STAs in the other BSSs of the MBSSID set can stay connected to their respective BSSs since those could avoid being reconfigured
<BG> That is correct Thomas. Limit the disconnects of devices to only the BSSID being upgraded (or to the MBSSID sets in case of TxVAP upgrade)
[V] Abhishek Patil (Qualcomm Technologies, Inc) • But there would need to be a down time when the hardware is upgraded to / replaced with the next gen - right?
<BG> Yes, AP HW refresh is carefully planned as I describe above. However, after the HW refresh, the BSSIDs typically start as the old gen (11be) and then those will be upgraded in phased approach over a period of time with one SSID at a time. During this phase a BSSID can be upgraded to 11bn, and if issues are observed then downgraded to 11be, fix the issue, then upgrade again and so on. Each of these steps resets all the BSSIDs in two MBSSID sets today (and disconnects clients). Our goal is to make minimize that blast radius.
[V] Ming Gan Huawei • yes in my mind
<BG> See my answer above on how AP HW refresh happens.
[V] Jarkko Kneckt, Apple • Can you upgrade Wi-Fi generation only by SW? I think you need some new HW for new frame formats, etc?
<BG> After the AP HW has been refreshed to the new gen AP HW (see my explanation above), then the AP device already has HW capability to support new Wi-FI generation. Then, the PHY gen of a BSSID can be upgraded from 11be to 11bn when desired by the custome - the AP device already has all the HW and SW needed for 11bn.
Thanks,
Binita
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