On Mon, 2023-11-13 at 10:11 +0800, Michael-CY Lee wrote: > The Wi-Fi Standard (IEEE 802.11-2020 9.4.2.160) initially specified that > the Wide Bandwidth Channel Switch (WBCS) IE subfields have same definitions > as the S1G or VHT Operation Information according to the operating band. > > However, it did not change the definitions in the amendment for 6 GHz > (IEEE 802.11ax-2021), so the logic remain the same for handling the WBCS > IE even if there is no VHT mode in 6 GHz. > > Now the Wi-Fi Standard draft (IEEE P80211be D3.2 9.4.2.159) modifies the > defitions, making the WBCS IE subfields follow the definitions of S1G, type - definitions > VHT and HE Operation Information in S1G, 5 GHz and 6 GHz band, respectively. > > APs in 6 GHz band might use the VHT or HE Operation Information to build > a WBCS IE according to the Wi-Fi Standard they follow. Originally, the STA Probably should say "Element" in place of all those "IE" - the spec stopped calling them "Information Elements" a long time ago :) > just parsed the WBCS IE as VHT Operation Inforamtion, which was wrong if > the AP was actually build the IE by the HE Operation Information. > > To avoid the ambiguity, STA should prefer the op_class in the Extended > Channel Switch Announcement (ECSA) IE rathen than the WBCS IE. If the ECSA typo - rather > IE is not presented in a channel switch to 6 GHz, the STA should be aware > of the possible ambiguity when parsing the WBCS IE. > > To derive the correct bandwidtin in use, the STA should check the typo - bandwidth in > + case 4: > + /* 320 MHz bandwidth > + * TODO channel switch to 320 MHz bandwidth should be indiated > + * by Bandwidth Indication IE (IEEE P80211be D3.2 9.4.2.159) > + */ > + he_6ghz_oper->control = IEEE80211_EHT_OPER_CHAN_WIDTH_320MHZ; > + break; I'm not sure what this TODO was meant to refer to, but I do know that D4.1 made some changes here, maybe we should check those? I haven't even checked what the changes are though. In any case, checking with a newer draft and using that would seem useful? Haven't really read all the other things here yet, this just caught my eye since I also just heard about D4.1 changes, but I don't have that or even the old stuff all in my head right now. johannes
