Trouble with key rotation in noisy environments [resend]
apenwarr at gmail.com
Mon Oct 27 19:55:48 EDT 2014
[Resending since my message was rejected - not subscribed to the list.]
Can anyone else reproduce this? I'm using ath9k and ath10k APs with
the latest hostapd from HEAD (though we've tried several other
versions without any difference).
- Pick a channel in a noisy environment (eg. 2.4 GHz)
- Configure hostapd to rotate keys extremely frequently:
- Connect a client device (tested with Macbook Air and two different
- On the client, load a tool like http://gfblip.appspot.com/ to
generate and monitor continuous traffic.
- On the AP, watch the hostapd logs to see key rotations as they happen.
- Key rotations occur every 10 seconds or so but do not affect the traffic.
- Most key rotations go through fine and don't show latency spikes in
the "blip" application linked above.
- Every now and then, something goes wrong with the key rotation and
data stops flowing. The AP thinks the key rotation has worked, but it
apparently has not.
- After about 10 more seconds (possibly because that is the next key
rotation), hostapd decides the station is broken and disassociates it.
- Immediately afterward, the station reconnects and resumes its
activity, and the cycle repeats.
I would appreciate any hints you all can provide.
More information about the HostAP