Periodic re-authentication with wpa_supplicant

[Jouni Malinen]

On Wed, Nov 24, 2010 at 06:27:59PM +0100, Julien Herzen wrote:
> The connection works well. However, we are having troubles with the IT
> department of the university because our nodes keep re-authenticating
> themselves, which seems to consume a large amount of resources of the
> infrastructure.

How frequently is this re-authentication happening?

> The whole re-authentication process seems to be triggered by the "RX EAPOL"
> event. Does anybody knows whether this means that it's actually triggered by
> the infrastructure?

This was indeed triggered by the authenticator. What made it decide to
re-authenticate the device is another question, but I would not expect
it to be wpa_supplicant. A more complete debug log with timestamps (-ddt
on command line) showing couple rounds of re-authentication could
provide more complete picture on what exactly is happening.

> What is the role of "authWhile"? Can it be the event that triggers the
> re-authentication?

It is used to figure out if a request from the authenticator has timed
out. I don't think it would trigger re-authentication since it is used
only during an ongoing authentication attempt.

> Apparently, this behavior does not happen with "regular" PCs. We are using
> OpenWRT on embedded wireless boxes... might that make any difference?

Do you have access to the Authenticator (switch?) debug log? Maybe there
is a link down/up event etc. triggering re-authentication.

-- 
Jouni Malinen                                            PGP id EFC895FA