Subject: Re: [PATCH 4/4] mac80211: Add IEEE802.11n for IBSS
From: Alexander Simon <alexander.simon@saxnet.de>
To: linux-wireless@vger.kernel.org
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Date: Fri, 29 Apr 2011 10:37:44 +0200
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> Yeah it would be an option to just always join as HT if HT is available,
> but not create as HT unless asked.
Ok. I just had a few thoughts about this:
This way an ht ibss has to be created from a (patched) mac80211 HT
hardware. There would be no way to "convert" an existing g network into
n.
Additionally, if a non-ht implementation joins the network, it will
advertise it as non-ht. If a second ht-station joins from one of these
beacons, it won't use ht.

This way a single non-ht station could destroy a ht ibss.


I Think the best way to go would be to obey HT information when joining
HT but using the HT iw parameter when joining non-ht.

Then we could have the following scenario: Non-HT station A creates
non-HT.
HT station B joins and sets HT- (from iw). HT station C joins from A but
doesn't see B. It's iw parameter says ht+.
But when B comes closer to C do a "HT merge", comparing TSFs.

Conclusion:
- Create an ibss with the iw parameter
- When joining a ht ibss, use its parameters
- When joining non-ht, add ht from iw parameter
- When encounter a different ht config, do a ht merge.