From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Stuge Date: Thu, 24 Feb 2011 09:20:42 +0100 Subject: [ath9k-devel] What would be the best chipset for wireless router/AP on linux? In-Reply-To: References: Message-ID: <20110224082042.19810.qmail@stuge.se> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: ath9k-devel@lists.ath9k.org crocket wrote: > Do those messages imply that I can't use 5Ghz frequencies in AP > mode with ath9k and AR9280? Luis R. Rodriguez wrote: > this varies by card. To clarify further that's the card itself, and not the chipset that is on the card. The chipset is capable of "everything" but because "everything" is not legal everywhere in the world, the chipset needs to know what parts of "everything" should be disabled so that the user is not breaking local laws. The information about what to disable is the regulatory domain stuff. Reg domain is specified in multiple places, and each reg domain clue always disables things and never enables things. It all starts with a value that is stored in a small memory chip besides the main chipset on the actual wireless adapter PCB. When that memory says "world" reg domain, because the card was not manufactured to be sold in any particular country, the chipset is running very much dumbed-down so that it is legal regardless of which country it will be used in, and there is no way to increase the capabilities from software. The regulations for 2.4GHz are somewhat similar worldwide, for 5GHz not so much. All companies making these products are bound by law to do nothing about this. The only thing that will work in the short term is to let users change the reg domain in this memory on the card. No such tool exists just yet however. Yes, it's a bit of a mess, as always with international law. //Peter