Carbonite has updated its online PC backup product. For a uniform price Carbonite version 3.5 provides an "all you can eat" style online backup service aimed at consumers and SMEs.

The company offers unlimited backup for $59.95 per year.

"It's one price no matter whether you back up one gigabyte, five, fifty, or a hundred gigabytes," said Floyd Bradley, executive vice president for Carbonite international.

"We even have two dozen customers who have over a terabyte. They are not our most profitable customers as you can imagine, but we find it's convenient to offer a one size fits all, all you can eat style for one price."

Carbonite 3.5 works by scanning for new and changed files on a PC. The software then automatically backs up those files in a two stage encryption process inside Carbonite's earthquake and fire-proof data centre. The data centre is located in Boston, Massachusetts, and is shared with British Telecom, France Telecom, AT&T and other high profile telecommunications companies.

The data centre uses RAID 5 and RAID 6 backup architecture. If any corruption occurs Carbonite automatically re-downloads the file from the users PC. Currently, over 3 billion files totaling more than 2,700,000GB are stored in the data centre.

"It backs up everything by default; Powerpoint, Excel or Word files, PDFs, emails, JPEGs, MP3s, video files, all the typical user files," Bradley said.

Carbonite does not automatically backup executable files, system files, temporary files or individual files greater than 4GB.

"But you can always right click on something and force a backup so if you want to backup your executables or applications you can do that."

Bradley said the Carbonite user interface is tied to the Windows experience, and uses coloured dots on a file icon to indicate whether that file has been backed up.

"So if you want to have a quick glance at what is backed up, the green dot will say that file has been backed up to our data centre, and the yellow dot means this file has been changed or is new and hasn't been backed up yet."

Customers can backup as much as they have on their computer, the only constraint being the speed of their Internet service.

The software uses a password tied to the users email account to gain access to the data centre, but is keyed to the PCs serial number in case a user loses their password. A license transfer is required prior to restoring data to a different computer.

Carbonite's emergence came in response to numerous studies that found high numbers of people that considered their data to be either valuable or priceless, but a significant number of those people were not backing up at all or had never backed up.

"We have a very strong purpose, we only focus on backup, that is all we do. We live, breathe, eat and sleep backup," he said.