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Date: Mon, 20 Feb 2012 16:41:06 +0530
Message-ID: <CAD2nsn3PKg5J2t-bdzrg6=pagejxtf3c0LXg1wS0ii2FGFQkmw@mail.gmail.com> (sfid-20120220_121111_313747_3D3C3B5D)
Subject: Re: AP send null-data packet?
From: Mohammed Shafi <shafi.wireless@gmail.com>
To: Johannes Berg <johannes@sipsolutions.net>
Cc: Christian Lamparter <chunkeey@googlemail.com>,
	Yingang Fu <yingang.fu@gmail.com>,
	linux-wireless@vger.kernel.org
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> Yes, this is true, it happens when the station sends a PS-Poll but we
> timed out the frame in the meantime -- should be uncommon. In the uAPSD
> case it's more common, if nothing is pending and the station sends a
> trigger frame.

thanks!

>
> In any case, it's perfectly normal for an AP to send null data frames.

-- 
thanks,
shafi