On Thu, 2014-03-20 at 10:39 +0100, Michal Kazior wrote: > >> The spec also defines VHT BSS operating channel width is derived from > >> HT Operation Element: STA Channel Width field (Table 10-19) and 20 MHz > >> is not forbidden for AP/mesh. hostapd seems to go in line with this > >> and allows VHT20 and VHT40. > > > > Yes but how is that related to the *capability* bit? You're talking > > about the HT/VHT operation information. > > Good point. > > Hostapd sets *both* HT Capability and HT Information IEs to "only > 20Mhz" for VHT20. I can see Cisco EA6500 do the same thing too. That used to be fine for HT only, but I guess it's wrong for VHT. It also means that it cannot switch to 40 MHz on the fly later. > > So are you saying the station isn't setting 20_40 capability? Or is > > something else unsetting the bit in case it's a 20MHz network? > > In case of AP mode you get ht_capa/vht_capa from userspace (i.e. > hostapd). This would again imply hostapd does it wrong or is it > perhaps the interface describing HT/VHT state is insufficient? Should > mac80211 treat HT Capab and HT Info separately? Should they be passed > and processed separately? It's possible that the interface is insufficient (*), but I'd argue that if that is the case then it'd be a question of setting the operation mode rather than any per-station information, since the per-station information should really be capabilities, while the current operation mode should be for the interface? If the kernel knows what it's operating as (*) and knows the station capabilities, everything else should be clear immediately, no? (*) right now I suspect that the channel bandwidth is used, which might be incorrect if we ever want to implement dynamic bandwidth switching in the AP johannes -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
