Apple has updated the firmware of AirPort Extreme Base Station with 802.11n. According to the company, this firmware release “includes all fixes in Firmware 7.1 plus additional compatibility updates for the AirPort Extreme Base Station with 802.11n.”
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It is my understanding that the 802.11n standard specification is still not final. I’m assuming that this may be why I’m having interoperabilty issues with other devices that conform to the “proposed standard”.