From owner-freebsd-wireless@FreeBSD.ORG  Tue Feb 14 08:19:41 2012
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Date: Tue, 14 Feb 2012 09:19:40 +0100
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From: Monthadar Al Jaberi <monthadar@gmail.com>
To: freebsd-wireless@freebsd.org
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Subject: Fragment number of first fragment != 0
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Hi,

I found that in FreeBSD current the first fragment will have a
fragment number = 1 in function ieee80211_fragment.

But according to 802.11-2007, 9.4 Fragmentation page 279:
"...The fragments shall be sent in order of lowest fragment number to
highest fragment
number, where the fragment number value starts at zero, ..."

This also holds on the 802.11-2011 draft 12:
"The fragment number is set to 0 in the first or only fragment of an
MSDU or MMPDU and is
incremented by one for each successive fragment of that MSDU or MMPDU."

I checked Linux 3.3-rc3 code and there I see them having a check on rx side
if (frag == 0) { /* This is the first fragment of a new frame. */
and on tx side they put:
fragnum = 0;

On Madwifi 0.9.4 in function ieee80211_encap:
fragnum = 0;

So should we change our fragno to be 0?

br,

-- 
Monthadar Al Jaberi