But Couture warns that many MSSPs price their services differently.

"Some of them charge you for the largest backup you made in a one-month period; some of them charge you for the amount of data you're protecting on the server; some of them charge you for every [gigabyte of storage] you've written to or from," Couture says. He recommends asking competing MSSPs how much it would cost to protect a given amount of data to get "an apples-to-apples comparison."

Scheier is a freelance writer in Boylston, Mass. Contact him at rscheier@charter.net.