Is wpasupplicant 0.7.3-6 compatible with 5Ghz band steering?

Ed W lists
Sat Mar 31 15:29:08 PDT 2012

On 31/03/2012 19:47, Jouni Malinen wrote:
>> Then, do you have an idea why wpa_supplicant would forcibly disconnect from
>> a 5Ghz 70/70 signal to go seek a 2.4Ghz signal?
> The 2.4 GHz signal was likely reported with stronger signal strength.
> The 70/70 part is not that helpful since the exact meaning of the signal
> quality is not really defined that well..

Hi, is there a quick summary of the selection algorithm in current git 
so that I can try and peek at the code to understand what i'm seeing?

My very quick observation is that I'm testing latest 1.0-git branch, but 
I "select" a network with high signal strength, this disables all other 
networks, I then use wpa-cli to "enable" all other networks, then after 
some few seconds I see wpa_supplicant suddenly disconnect and roam onto 
a network with much lower (-20db or so) signal strength.  It seems to do 
this fairly reliably...

Annoyingly (and related to my previous question yesterday), if I 
deliberately stack my wpa_supplicant.conf with additional network blocks 
with incorrect wpa and wep keys, then I can frequently trigger a 
situation that wpa_supplicant roams off a working network, connects to a 
bunch of non working networks and then appears to give up and stop 
scanning and remain on a network where I know the passphrase is 
incorrect...  This is a little frustrating (although contrived) given 
that we started on a working network... (it sometimes seems to detect 
that a network isn't working and roam to another, but I am struggling to 
understand when/why? also what happens if I include a network block 
twice with two different passphrases - how does it know when to try both 
and how does it know which succeeds?)

I suspect I need to probe much more carefully into the signal strengths 
and what is going on here, but any chance of a basic heads up on the 
algorithm so that I can try and look under the bonnet some more?


Ed W

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