How to tell wifi standard (b/g/n) during scanning?

[Dan Williams]

On Tue, 2016-12-20 at 18:05 +0200, Flavius Lazar wrote:
> Hello,
> 
> I'm using wpa_supplicant to scan for wifi networks.
> Is it possible (how?) to identify which wifi standard (802.11 b/g/n,
> 802.11b, ...) is configured on the detected APs?

You'd look at the IEs (extended rates, HT, VHT, etc) included in the
scan results.

For example, if the AP supports 54Mbps rates, then it probably supports
802.11g.  If it supports higher than 54Mbps then it probably supports
802.11n.  If it supports rates higher than 135Mbps, it probably
supports 802.11ac.

If it supports 40MHz channels, it probably supports 802.11n.  If it
supports 80MHz and larger channels, it probably supports 802.11ac.

I believe you can get the IEs in hex format from either wpa_cli or the
D-Bus control interface in byte-array form.  Yeah, you have to parse
them yourself, but they are a very well-known format.

Dan