Subject: Re: [RFC] mac80211: Re-enable aggregation
From: Johannes Berg <johannes@sipsolutions.net>
To: Sujith <m.sujith@gmail.com>
Cc: "linville@tuxdriver.com" <linville@tuxdriver.com>,
	"linux-wireless@vger.kernel.org" <linux-wireless@vger.kernel.org>,
	Luis Rodriguez <Luis.Rodriguez@Atheros.com>,
	"tomasw@gmail.com" <tomasw@gmail.com>
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Date: Mon, 27 Oct 2008 16:07:45 +0100
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On Mon, 2008-10-27 at 19:41 +0530, Sujith wrote:

> > > How would mac80211 buffer frames ?=20
> >=20
> > Well I suppose it would just put them on a list in the sta_info struct.
> >=20
>=20
> A list for each TID, no ?

Right.

> To summarize a bit about the state/control information that mac80211 need=
s
> to maintain for an aggregation session:
>=20
> * Block Ack state for each TID (sequence numbers, BA window etc.)
> * Maintain a list of buffers for each <RA,TID> (setup, teardown etc.)
> * Handle retransmission of unacked frames.
>=20
> Forming an aggregate would involve the following.
> ( These might depend on HW caps as well as the recipient STA's caps)
>=20
> * Aggregate length
> * Delimiters
> * Padding of sub-frames
>=20
> TX control information will probably need to pass aggr. specific informat=
ion
> (number of delimiters etc.)
>=20
> The API for aggregation can extend the ampdu_action() callback.
> Adding a few more states can probably suffice initially.

Sounds good to me. If you need more space in TX control information...
Not sure what to do then. We could take out 'vif' and put that into the
tx() arguments instead, for example.

> We'll work on this and come up with an RFC.

Great!

johannes

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