Most small businesses and home-office workers rely on an external hard drive, tape drive, or even just a CD/DVD, to back up their critical data and files.

But is that the best approach? Well, it’s better than no approach. (Let’s face it. How many of us has gotten the blue screen of death only to realize that last backup was a week or a month or… ahem…a year ago?)

I can tell you firsthand that when the unexpected happens - and it does - onsite backup can be as bad as no backup. When my house caught fire two years ago, I watched the black smoke pour from my windows and wondered if I would ever see my primary or backup data again. Fortunately, my soot-covered laptop fired up long enough for me to copy the data. But my external drive? Melted.

So what’s the best way for home offices and small businesses to back up data? I advocate hosted services that are replicated in hardened data centers. They not only diminish the repercussions of a disaster, they enable remote access from an Internet connection.

AT&T last week announced enterprise-grade online services called “Online Vault” and “Remote Vault” aimed at both consumers and small businesses.

The service performs an initial backup of all files, and then regularly backs up new files and changes to existing files each day - and more frequently for businesses.

What’s particularly good about the service is that data is stored at AT&T hardened data centers, and files are compressed and encrypted before they’re stored. And, if you delete files on the local drive, you can retrieve them for up to 30 days under the consumer service and up to four months under the business service.

The consumer and small business services are affordable, with the former priced at $5.95 per month for 2GBs of storage, another $2 per month for each additional 2GBs of storage, and a maximum price of $17.95 per month for unlimited storage. The business service costs $6.95 per month for the first gigabyte and $2 for each additional gigabyte. Server backup costs between $6 and $12 per gigabyte.

AT&T isn’t the only such service that exists for small business and home workers. There are numerous hosted services, including Carbonite, Iron Mountain/LiveVault, and Xdrive. Other services can be cheaper, but AT&T may be a decent solution for IT managers who want to consolidate the number of providers they work with, or for those who inherently trust AT&T’s hardened data centers.