On Fri, May 05, 2006 at 03:14:35PM -0500, Larry Finger wrote: > * A new routine (ieee80211_init_geo ?) will be written to be called by the > driver to load the geo structure into the kernel. Information passed to the > daemon will be the country code in ASCII and whether the interface is to be > used indoors or outdoors.
The driver may not know the country code, so there should be mechanism for user space to override this. > * Checksum routines will be used to validate the data base. Such a simple > scheme will not inhibit anyone with moderate skills from hacking the > channel/power settings, but such hacking will require some effort. I did not see this included in the example file. Did you have more detailed plans on how this would be done? > * Each channel in the resulting kernel data structure will have appropriate > flags set indicating if it is to be used indoors, outdoors, or both. In > addition, if the channel should be used only for passive scanning, a > suitable flag will be set. In the 2.4 GHz band, a flag will indicate if it > should be used for 802.11b, otherwise both b and g mode will be assumed. In > the 5.0 GHz bands, a flag will be set if the channel is to conform with > 802.11h or 802.11a standards. 802.11h, radar detection, and DFS may need to be more complex than just a one-bit value of it being enabled. Countries may have different requirements for different areas related to 802.11h.. > The database consists of two sections. The first relates the Country Codes > to a wireless group. The second section describes the channel parameters > for the groups. Shown below is a fragment showing the Country Code - Group > info for a few countries and the definitions for a few of the groups. One way to compress this and possible make maintaining quite a bit easier would be to use two different set of groups: one for 2.4 GHz band and another one for 5 GHz band. Many countries share the same requirements for 2.4 GHz, but have different 5 GHz requirements.. This is not really a requirement, but could end up making this easier to use. > Number of Countries: 100 > Number of Groups: 15 These are not really needed and unless a tool is used to update this file, they will most likely end up being out of sync at some point ;-). The parser can just read through the file twice if it need to know these numbers before parsing (though, that should not really be needed with dynamic data structures).. > # group Country Code Description > # > 1 AT Austria (Standard EU) > 1 DE Germany (Standard EU) > 2 FRI France Indoor (Not Guyana or La Reunion) > 3 FRO France Outdoor (Not Guyana or La Reunion) > 4 FR1 French Departments of Guyana and La Reunion Indoor > 5 FR2 French Departments of Guyana and La Reunion Outdoor Country code has to be two characters to fit into country IE.. AT and DE are a good example of possible use for different 2.4 GHz and 5 GHz groups.. If I remember correctly, they have the same rules for 2.4 GHz, but different for 5 GHz.. (unless--of course--they already changed them since I looked last time.. ;-) > # Ch. Range - Minimum and Maximum Channels for this range > # Ch. Spacing - Number of channels between adjacent entries Other option would be to use start channel and number of channels. Channel spacing is also fixed in practice (1 for 2.4 GHz, 4 for 5 GHz), so it may not be needed here. > # Power in mW EIRP I would prefer to see the maximum TX power in dBm, not mW. > # Flag Codes > # B - Both Indoor and Outdoor > # I - Indoor Only > # O - Outdoor Only > # P - Passive Scan Only Some more flags may need to be added in the future. It looks like the format used here makes this trivial to extend. -- Jouni Malinen PGP id EFC895FA - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
