Re: Delay in association with ipw2200

> Hi All,
>
> We are noticing a delay of approximately 335 milliseconds, during the
> reassociation to a new accesspoint.
> When the card is to associate with a new access point, it is intimated via
> the iwconfig essid command. During this time, after the association, the
> card sends an interrupt (link_down) and followed by another interrupt
> (link_up), the time difference between the two being around 335 milli
> seconds.
>
> I want to know why the wlan card takes this time from link_down to link_up.
> Is there a way to reduce this delay?
>
> Please help me in understanding this delay.
>
> Many thanks in advance.
>
> Regards,
> Basavaraj

Hi,

I am experiencing the same problem, but for me it has a far more serious 
effect: I am writing an IP mobility application, which relies on wireless 
events from Linux kernel. So, when the client associates with a new AP, a 
RTM_NEWLINK event with IFLA_WIRELESS attribute type is being generated by 
ieee80211 subsystem (on the basis of ipw2200 notifications I guess). I can 
receive that event in userspace, which serves me as an asynchronous 
notification that we're in the other WLAN now. The problem is that after I 
get this wireless event, I still have to put an additional sleep() of around 
800ms to my program, otherwise no packets can be sent out via wireless 
interface (driver's TX-debug doesn't show anything either). They just get 
dropped.

This is very strange, because this event is the only wireless event about new 
associations, and it turns out it is in some way incorrect, because after 
this event the interface is still not ready to send out data.

Is there some way to get informed by the kernel whether the association is 
COMPLETELY done and the interface is FULLY ready?

Regards,
Eugene

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