Skip site navigation (1)Skip section navigation (2)
Date:      Wed, 27 Jan 2010 20:04:09 +0100
From:      Alexander Egorenkov <egorenar@googlemail.com>
To:        freebsd-net@freebsd.org
Subject:   A-MPDU transmission in net80211 on FreeBSD 8
Message-ID:  <2d3b7e441001271104j14836df4j14428d34561dead1@mail.gmail.com>

next in thread | raw e-mail | index | archive | help
Hi,

i'm implementing a device driver for a 802.11n NIC under FreeBSD 8
und experimented with A-MPDU transmission. I looked into net80211 code
and there is some code which implements this feature but it worked not very
well for me.
I noticed e.g. that sequence numbers are not assigned to A-MPDU frames
and found this comment in file ieee80211_output.c :


/*
         * Check if A-MPDU tx aggregation is setup or if we
         * should try to enable it.  The sta must be associated
         * with HT and A-MPDU enabled for use.  When the policy
         * routine decides we should enable A-MPDU we issue an
         * ADDBA request and wait for a reply.  The frame being
         * encapsulated will go out w/o using A-MPDU, or possibly
         * it might be collected by the driver and held/retransmit.
         * The default ic_ampdu_enable routine handles staggering
         * ADDBA requests in case the receiver NAK's us or we are
         * otherwise unable to establish a BA stream.
 */

Can somebody elaborate this description to me please.

Thanks.

ALex.



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?2d3b7e441001271104j14836df4j14428d34561dead1>