Computer server backup administrators are staring down tougher and tougher requirements. Traditional data backup technology can be good at protecting a business, if it is possible to wait days to recover from a disaster. But businesses can't wait that long to recover their data from backup tapes before they do business again.

Mostly, businesses need to recover only a few files from a backup because of viruses or deletions. But traditional backups are no good at doing that within a day.