On Friday 29 September 2006 17:10, James Ketrenos wrote:

Johannes Berg wrote:

quoted

 * Should the userspace daemon be allowed to unilaterally update the
   regulatory information if it learns something new (via the user)?

Many countries forbid users (root is still a user) being enabled to
override the parameters set up by the hardware vendor as tested for use
with a specific device.

If the hardware and/or driver for the hardware advertises a set of
operating parameters, user space should honor those settings and the
kernel should enforce them.

This makes 802.11d impossible. There are already many ways of violating local 
regulations. We should not make it easy to override the regulatory domain 
parameters, but going out of our way to make it hard is not gonna work.

With hardware that restricts operation to the capabilities it was tested
and calibrated for, this will likely result in a broken user experience
-- if they try and use a device on channel 13 and the device restricts
operation to channels 1 - 11, tuning operations will fail.

So the hardware should not even restrict tuning to channels 1-11, for example. 
That sort of enforcement belongs in the kernel, with information imported 
from userspace so parameters for various regulatory domains can be updated 
easily. (whereas with hardware enforcement, every change requires new 
firmware) Sure, it's a bit easier for an enthusiastic user to set the TX 
power too high or tune to channel 14, but it seems likely that the number of 
people who would do that is a bit smaller than the number of people who 
travel between different countries frequently (and would benefit from 
easy/automatic regulatory domain switching).

-Michael Wu