Date: Fri, 24 Feb 2017 08:55:19 -0600
From: Seth Forshee <seth.forshee@canonical.com>
To: Ryan Mounce <ryan@mounce.com.au>
Cc: wireless-regdb@lists.infradead.org, linux-wireless@vger.kernel.org,
        Johannes Berg <johannes@sipsolutions.net>
Subject: Re: [PATCH v2] wireless-regdb: Update rules for Australia (AU) and
 add 60GHz rules
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On Fri, Feb 24, 2017 at 01:20:24PM +1030, Ryan Mounce wrote:
> On 24 February 2017 at 02:05, Seth Forshee <seth.forshee@canonical.com> wrote:
> > On Fri, Feb 24, 2017 at 12:22:53AM +1030, Ryan Mounce wrote:
> >> Sourced from the current legislation at
> >> https://www.legislation.gov.au/Details/F2016C00432
> >>
> >> The current rules exceed legal limits between 5250-5330MHz, and permit
> >> illegal operation in 5600-5650MHz (disallowed regardless of DFS).
> >>
> >> Frequency ranges and EIRP limits for all ranges have been updated to
> >> match items 59-63, 65 in the linked document. As the rules for AU have
> >> never previously mirrored local regulations, changes include a
> >> significant increase in the allowable 2.4GHz EIRP and smaller increases
> >> in most other bands.
> >>
> >> In order to allow 80MHz operation between 5650-5730MHz (bordering two
> >> bands) the lower, more restrictive band has been rounded up by 5MHz.
> >>
> >> Signed-off-by: Ryan Mounce <ryan@mounce.com.au>
> >> ---
> >>  db.txt | 15 ++++++++++-----
> >>  1 file changed, 10 insertions(+), 5 deletions(-)
> >>
> >> diff --git a/db.txt b/db.txt
> >> index 05108e0..00e81b6 100644
> >> --- a/db.txt
> >> +++ b/db.txt
> >> @@ -85,12 +85,17 @@ country AT: DFS-ETSI
> >>       # 60 GHz band channels 1-4, ref: Etsi En 302 567
> >>       (57000 - 66000 @ 2160), (40)
> >>
> >> +# Source:
> >> +# https://www.legislation.gov.au/Details/F2016C00432
> >> +# Both DFS-ETSI and DFS-FCC are acceptable per AS/NZS 4268 Appendix B
> >>  country AU: DFS-ETSI
> >> -     (2402 - 2482 @ 40), (20)
> >> -     (5170 - 5250 @ 80), (17), AUTO-BW
> >> -     (5250 - 5330 @ 80), (24), DFS, AUTO-BW
> >> -     (5490 - 5710 @ 160), (24), DFS
> >> -     (5735 - 5835 @ 80), (30)
> >> +     (2400 - 2483.5 @ 40), (36)
> >
> > The mention of ETSI EN 300 328 in item 55 (a) leads me to believe that
> > this is the limit we should be using, i.e. 500 mW. It is a bit confusing
> > though since it seems like such devices would also fall under "digital
> > modulation transmitters."
> 
> Item 55 applies only to frequency hopping transmitters e.g. Bluetooth.
> As a local, I can say with some degree of certainty that 4W/36dBm is
> the correct 2.4GHz ISM EIRP for Australia. It is advertised as the
> EIRP in the 802.11d IE of commercial devices e.g. Cisco Aironet APs
> and widely deployed ISP gateways in Australia, among other devices
> that have received relevant approvals.

Okay, looking at that section again that makes sense.

> >> +     (5150 - 5250 @ 80), (23), NO-OUTDOOR, AUTO-BW
> >
> > This looks correct.
> >
> >> +     (5250 - 5350 @ 80), (23), NO-OUTDOOR, AUTO-BW, DFS
> >
> > Since this range requires TPC we need to set the power limit at 100 mW.
> >
> >> +     (5470 - 5600 @ 80), (30), DFS
> >> +     (5650 - 5730 @ 80), (30), DFS
> >
> > These ranges also require TPC so we need to set the limit at 500 mW.
> 
> I was unsure about this one. Setting this to 27dBm also affects the
> 802.11d country information IE, however when the DFS flag is set a 3dB
> 802.11h power constraint IE is also advertised so stations will limit
> themselves to (27-3)=24dBm/250mW.
> 
> Given the choice between unnecessarily halving transmit power on
> stations and potentially transmitting at twice the permissible power
> on APs without TPC I agree that the conservative approach should be
> taken for now. Ideally I think that the actual EIRP limits should be
> in the regdb and a 3dB constraint should be applied automatically on
> APs that cannot support TPC when the DFS flag is set.
> 
> >> +     (5730 - 5850 @ 80), (36)
> >
> > In the document the ranges are 5650-5725 MHz and 5725-5850 MHz. I
> > suspect that the existing rules fudge that to line up with the wifi
> > channels, which technically is okay because the rules in the former
> > range are more restrictive. I wonder if we shouldn't be recording them
> > here as per the document and adding AUTO-BW. Johannes, any thoughts?
> 
> I've tested with AUTO-BW and it doesn't work in this case as channel
> 144 will be disabled if it doesn't exist entirely within one band.
> Fudging the more restrictive rules by a mere 5MHz to fit 802.11
> channels seems to be the status quo.

I wonder why AUTO-BW doesn't work. In that case it's certainly fine to
keep those ranges as they are.

Thanks,
Seth