P2P NOA invalid parameters

Jouni Malinen j at w1.fi
Mon May 28 01:03:36 EDT 2012

On Wed, May 23, 2012 at 09:33:52AM +0200, Piszcz Pawel wrote:
> Parameter list to set NOA contains : count, start_offset, duration,
> interval.  Are there any rules regarding invalid ranges or combination
> of duration and interval?  Of course interval should be longer than
> duration, but if duration consumes 90% of interval does it still
> make sense?

Well, it may make sense for some use cases, but it comes at the price of
other devices finding it more difficult to connect to the GO.

> Second problem is how long duration is allowed. I think when I define
> 90% sleep time then interval longer than 1sec also make no sense.
> In other words if GO will go to sleep for too much time then there
> will be a problem, with connecting/disconnecting to this group-owner.

If the GO is only sending out the Beacon frames and spending pretty much
all other time away from the channel, it may be difficult to find that
GO unless you are already associated.

> Should the validation be performed in supplicant or in driver?

wpa_supplicant should have nothing to do with NoA values apart from some
testing uses. It is up to the driver to figure out the exact NoA
parameters based on what kind of other needs there are for the radio
(concurrent uses or power saving).

Jouni Malinen                                            PGP id EFC895FA

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