To be truly effective, a backup application must let you easily choose what you back up, simplify recovery and not slow down your work. So I was looking forward to evaluating DataSentinel, a combination of hardware, software and storage service.
The hardware -- a 512MB thumb drive -- comes preloaded with the backup software. The software loads automatically (and prompts you for a password) when you insert the thumb drive in any USB slot. The files you select are stored on DataSentinel's servers, for which you pay a fee, beginning at US$5 a month for the first 5GB.
The idea behind DataSentinel is a good one. On the plus side, installation is simple. You insert the thumb drive in a USB port and the program asks you to verify your user ID and password. During installation, your password generates a 136-character "Personal Encryption Code" that you must keep safe. Should you lose your thumb drive, the code is required to recover your data, though the hard copy's black characters against a green background didn't produce a clear printout on my HP LaserJet monochrome printer.
After you've installed the drive, the next step is to select the folders and/or files you want stored on DataSentinel's servers by checking boxes in a tree view (see Figure 1). You can also check boxes to exclude files of a particular type (for example, audio files such as MP3 and WAV files), but you have no control over the file extensions for each type. You can also exclude files larger than a user-specified size.
Once you've made your file/folder selections (which you can change at any time), the program goes to work, backing up your files in the background. This is where it's clear how DataSentinel differs from other backup options -- when it works, that is. To prevent your system from grinding to a halt (a problem with most backup software), DataSentinel backs up at approximately 1MB to 5MB per minute, a speed that's slow enough not to interfere with foreground operations.
When I ran DataSentinel, backups ran at 3MB to 4 MB per minute -- a speed that varied depending on the ISP used. A progress screen (see Figure 2) shows the status of the backup, but I found that if I'd selected a large number of files, it often closed before it could calculate the percent complete. At other times, it reported the backup was 157 percent complete.