Time Capsule

March 30, 2009 (Macworld) The 2009 version of Apple's Time Capsule combines the mundane tasks of networking, file sharing, and backups into one device, and it includes some cool new features to boot. Time Capsule, basically an Airport Extreme base station with a 500GB or 1TB internal hard drive, is designed to be a wireless Time Machine target for one or more Macs as well as a NAS (network attached storage) device.

Time Capsule's marquee feature is its ability to back up your Macs running Leopard using Time Machine over the network. Apple recommends that you connect your Mac directly to the Time Capsule for the first backup, which makes a copy of all files on your Mac; backing up that much data takes a long time over the network. I backed up my MacBook Pro's 120GB of data to each Time Capsule connected via Gigabit Ethernet and it took a little over nine hours to complete the first backup.

After that initial backup, Time Machine will back up to the Time Capsule every hour (unless the Mac has been powered down or the previous backup took longer than an hour). These hourly backups are incremental--that is, they back up only files that have changed, or have been added since the last backup. Such backups take less time and are generally handily accomplished over a wireless connection. One thing to remember is that Time Machine backs up at the file level. So, if you use a program that frequently makes changes to a large central file (like Entourage, which stores e-mail in one large database file), Time Machine will back up that entire file, even if only one item in the file has changed. This can impact wireless backup performance, depending on how large those files are. You can also use one or more external USB drives attached to the Time Capsule's USB port as a Time Machine target.

The backup functionality hasn't changed with this new version of Time Capsule, so the same basic problems still exist: you can't swap out the internal drive, and even with the 1TB model, you may run out of disk space if you're backing up multiple Macs as well as using the internal drive for file sharing. (Theoretically, you should not run out of space, because Time Machine culls older backups; but users have reported that they have run out of room on the disk. Apple says that before OS X 10.5.5, Time Machine sometimes reported the Time Capsule drive as full when it was not. Also, Apple says that a rare problem with Time Machine backup image corruption on Time Capsule was corrected with base station 7.4.1 firmware and Mac OS X 10.5.6.) Speaking of file sharing, when we last reviewed the Time Capsule, file transfer speeds weren't exactly zippy. I transferred a 1GB video file to both Time Capsules, as well as to a Mac via AFP. Transferring the same file to either Time Capsule took about 33 percent longer than it did to transfer to the Mac. This is fine for occasional file sharing, but if you're doing a lot of file sharing, you might want to check into a dedicated NAS or Mac file server.