By Prince McLean

Published: 04:00 PM EST

New versions of Apple's wireless base stations supporting USB shared hard drives -- AirPort Extreme and Time Capsule -- have gained remote file sharing features via MobileMe. A firmware update is also expected to extend the feature to previous-generation models.

Back to My AirPort

"Say you’re traveling and you need a file on your Time Capsule back at home. If you’re a MobileMe member using a Mac with Mac OS X Leopard, no problem," Apple says. "You can now access all the files on your Time Capsule drive over the Internet. Simply register your Time Capsule with your MobileMe account, and its drive appears in the Finder sidebar of your Mac just like any other attached drive. It’s like having your own personal file server wherever you go."

A firmware update is soon expected to extend the new feature to existing models, in addition to the revised versions introduced today. Both units actually shipped with support for Wide Area Bonjour, but Apple didn't explain how to configure the systems, a procedure that requires setting up a public Dynamic DNS account and registering the base station with it.

With Mac OS X Leopard, Apple packaged a series of technologies together under the marketing name "Back to My Mac," including a Dynamic DNS service added to .Mac (now called MobileMe). Access to Dynamic DNS allowed Mac OS X to register its shared services, such as file shares and screen sharing, with MobileMe, making them discoverable, via Wide Area Bonjour, to any other Mac registered with the same MobileMe account.

Without the Dynamic DNS component, users would have to keep track of their home IP number (which is subject to change), manage port forwarding in Network Address Translation records for every system that was performing sharing, and supply the IP address and port numbers whenever they wanted to share files from a home system to a remote system. Back to My Mac handles all those tasks and relays them through MobileMe, making users' shares available to them anywhere on the Internet.



IPv6 Security

Back to My Mac also involves a security component. When a user on a remote system, authenticated with MobileMe, attempts to connect to a shared drive, a secure, encrypted IPv6 tunnel is created to protect the user's data from snooping as it moves between the home system and the remote computer over the Internet.

AirPort Extreme and Time Capsule can already be registered with a Dynamic DNS service. However, the soon to be released firmware update will automate this process by allowing users to simply enter their MobileMe account information into the base stations' configuration via AirPort Utility. Once configured, the base station will obtain the necessary security keys to set up secure remote access using the same MobileMe account.

The settings to enable a link with MobileMe will apparently be supplied in a base station firmware update numbered 7.4.1, according to a message posted by TUAW and attributed to an anonymous user with access to "the Apple Sales internal site." The current base station firmware version is 7.3.2. Once applied, the update will add a MobileMe button to the Advanced tab of the base station's configuration.

Note that this feature is not the same thing as certain "do it yourself" instructions posted on the Internet, which claim to "do the same thing without needing MobileMe" by simply opening up the base station's firewall and providing open and unencrypted access to its file shares.

Waiting for the other update to drop

The new firmware update will not provide new hardware-based features of the revised AirPort Extreme and Time Capsule, including the ability to operate both 2.4 GHz and 5 GHz networks at once or the ability to run a parallel guest network with its own password, isolated by firewall from the main network.

Apple has already begun distributing an AirPort Client Update which addresses issues with roaming and network selection in dual-band environments, and AirPort Utility 5.4.1 , which adds compatibility with the new features and client update. The 7.4.1 base station firmware is not yet available through Software Update nor Apple's software downloads site.