Subject: Re: ACK matching [was: TX status reporting with help of an ack
	queue]
From: Johannes Berg <johannes@sipsolutions.net>
To: Mattias Nissler <mattias.nissler@gmx.de>
Cc: Mikko =?ISO-8859-1?Q?Virkkil=E4?= <mikko.virkkila@bluegiga.com>,
	Ivo van Doorn <ivdoorn@gmail.com>,
	rt2400-devel@lists.sourceforge.net,
	"John W. Linville" <linville@tuxdriver.com>,
	linux-wireless <linux-wireless@vger.kernel.org>, dsd@gentoo.org,
	kune@deine-taler.de
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Date: Fri, 19 Sep 2008 12:31:05 +0200
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On Fri, 2008-09-19 at 12:19 +0200, Mattias Nissler wrote:

> Well, maybe we can work around this requirement? I still need to learn
> about the details, but what happens for example if the STA sends the ACK
> and then resets due to a crash? I guess the AP is able to cope with
> that, no? So maybe we can relax the rules a bit (unless we become really
> incompliant with the standard of course).

I don't really see how to. We can't just assume the station got the
frame properly and advance our state machine. The case you're citing is
quite different, we'll advance the state machine but it won't work
because the STA crashed; if we advance but the station simply hasn't
gotten the frame we'll get out of sync and stuff will fail for no real
reason.

But you can do workarounds all you want in hostapd, I don't care.
However, I do think that if the hardware just isn't up to the job you
should probably buy new hardware, after all, it's dirt cheap. :)

johannes

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