Apple today released AirPort Base Station Firmware Update 7.9.1 which improves the security of your base station and is recommended for all AirPort Extreme and AirPort Time Capsule base stations with 802.11ac.
For more information on the security content of this update see: http://support.apple.com/kb/HT201222
For detailed information on AirPort base station firmware updates, including instructions how to install the update, please visit: http://support.apple.com/kb/HT201519
For more information on using AirPort products, go to the Product Support Page at: http://www.apple.com/support/airport
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