Roaming ft-over-ds based on RSSI

[Dennis Bland]

> Date: Thu, 7 Jul 2022 05:30:09 -0700
> From: Ben Greear <greearb at candelatech.com>
> To: "hostap at lists.infradead.org" <hostap at lists.infradead.org>
> Subject: Roaming ft-over-ds based on RSSI
> Message-ID: <e5c4bd2c-1432-3155-ec50-8e67fe2bdb89 at candelatech.com>
> Content-Type: text/plain; charset=UTF-8; format=flowed
>
> Hello,
>
> While doing some testing with roaming based on changing RSSI (attenuation), we notice
> that we cannot do a proper ft-over-ds roam.  If we explicitly ask for ft-ds roam using
> wpa_cli, then it works as hoped.
>
> Maybe some extra code/config-options are needed in the logic that roams based on
> RSSI?
>
> Any suggestions for best way to go about that?
>

Back in 2019 we submitted an ft-over-ds patch to the hostap mailing
list to configure a preference for ft-over-ds via wpa_cli or the .conf
file, as we noticed wpa_supplicant would always use ft-over-air for
RSSI roams.  By enabling this option, wpa_supplicant would always use
ft-over-ds if supported by the AP, but still use ft-over-air if
ft-over-ds was not available.  In most cases, ft-over-ds is preferred
as the STA does not need to go off-channel to send the authentication
request to the target AP.

Unfortunately the patch was not accepted, and of course that time
period in the mailing list was somehow lost.  However, spinics still
has a cached copy:

https://www.spinics.net/lists/hostap/msg05809.html

Best regards,

Dennis Bland
https://www.dbperformance.com