802.11a/n

[Christian Lamparter]

On Tuesday, August 16, 2011 04:10:31 PM David Goodenough wrote:
> On Tuesday 16 Aug 2011, Jouni Malinen wrote:
> > On Mon, Aug 15, 2011 at 10:03:00PM -0700, Grant wrote:
> > > Thank you.  I get the following, it looks like the 5Ghz channels should
> > > work?
> > 
> > In station mode, but not in AP mode:
> > > 			* 5180 MHz [36] (19.0 dBm) (passive scanning, no IBSS)
> > > 			* 5200 MHz [40] (19.0 dBm) (passive scanning, no IBSS)
> > > 			* 5220 MHz [44] (19.0 dBm) (passive scanning, no IBSS)
> > > 			* 5240 MHz [48] (19.0 dBm) (passive scanning, no IBSS)
> > 
> > Those are fine in modes that passively search an AP and connect to it.
> > However, they are not available for starting an AP (or IBSS).
> > 
> > > 			* 5260 MHz [52] (disabled)
> > 
> > And those are disabled completely.
> As a side question, why would a card not be allowed to be an AP?  I can
> understand why it might not be capable of being an AP, but surely if anyone
> is allowed to be an AP (and having clients but no AP is no use to anyone)
> why are some cards not allowed to be an AP?
Because [at least in the US] the FCC dictates that an AP which
operates in the 5GHz band has to support DFS and TPC.

http://www.elliottlabs.com/documents/dynamic_frequency_selection_and_5ghz_band.pdf
[http://linuxwireless.org/en/developers/DFS]

Currently, neither DFS nor TPC are not implementated, therefore you are
not allowed to operate a 5GHz AP, the law is as simple as that.