Subject: Re: [PATCH v2] hostapd: remove vlan stuff
From: Johannes Berg <johannes@sipsolutions.net>
To: Jouni Malinen <j@w1.fi>
Cc: linux-wireless <linux-wireless@vger.kernel.org>
In-Reply-To: <20070817030649.GB1415@jm.kir.nu>
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Date: Fri, 17 Aug 2007 12:12:18 +0200
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On Thu, 2007-08-16 at 20:06 -0700, Jouni Malinen wrote:

> That would break the broadcast domain and if someone really want that,
> they could create a VLAN per STA..

Yeah, I was a bit confused here.

>  The purpose of using different group
> keys per VLAN is to allow each VLAN to have a separate broadcast domain,
> i.e., all broadcast packets to STAs bound to this VLAN are available to
> all STAs in this VLAN (and only to them).

Right.

> Since in 802.11 BSS networks, broadcast frames are only sent by the AP,
> hw acceleration can be made to work fine with this kind of
> configuration.

True.

> As far as the clients are concerned, they don't even know
> about the existance of different VLANs and group keys and as such, this
> looks a standard AP to them. As far as the AP is concerned, it will need
> to have support for using multiple keys with hwaccel and way of indexing
> them with each transmitted frame. Taken into account how support for
> hwaccel to unicast frames is implemented, this is quite a simple
> extension to that.

True as well, however, have you considered IBSS networks? As far as I
can tell, there you are actually able to put STAs into VLANs as well,
but you need to use per-VLAN group keys for receiving too.

johannes

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