MacOS – Change Mac OS X Wireless Card Country Code

macoswifi

I have problem connecting to a wireless router using Mac OS X which is on channel 13. This is because there is some other router nearby which is broadcasting the US country code. The only way around this i have found so far, is to each time go to the router and restart the computer.

I have asked google and it seems to be a mixture of people who think that it is setting the locale changes it, or that it is fixed in the router firmware. Both i have shown to be wrong. man ifconfig also has not been too enlightening.

Does anyone know of another way to force the card to use a different country Code or channels?
I would rather not change to another channel, as there is alot of interference near by (shown with KisMAC).

Thanks

Edits

Found

/System/Library/PrivateFrameworks/Apple80211.framework/Versions/Current/Resources/airport

Which appears to allow for an arbitary channel to be set on the card, but not county code. This seems to have no effect.

Best Answer

802.11d is the protocol that wireless access points use to broadcast (among other things) the regulatory domain (i.e. country codes) in which it is supposed to be operating. It seems that there may be no clear rule for what to do when various equipment is broadcasting conflicting regulatory domain information.

The ideal solution would be to disable/replace/reconfigure the equipment that is broadcasting the incorrect information.

I found an (oldish) Apple Discussions thread that indicates that indicates that a Mac’s AirPort hardware will use the first country code it hears after powering on or waking from sleep. Later postings in the thread (on the second page) indicate that it is sufficient to just power off/on the AirPort hardware itself and not the whole system. A couple of people reported success using a script to repeatedly turn the AirPort interface off and on (using networksetup) until it happened to acquire the desired state (as reported by system_profiler).

Based on TA25972, it seems that older equipment (presumably models that do not listen for 802.11d information) may not even be able to switch “country codes”.

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