Enterprise product works online or offline.

HP has extended its Data Protector software to cover mobile workers using laptops as well as other enterprise infrastructure, providing continuous backup and restore protection for data held on mobile clients.

The HP Data Protector Notebook Extension takes a continuous backup of data files as they are saved, and sends changes back to a central data vault, HP said. If the laptop does not have a network connection, backup data is held in a local repository until it can be transferred to the vault.

According to HP, a growing proportion of employees are equipped with laptops, but the business information they contain is seldom backed up, because the user is often on the road and disconnected from the corporate network much of the time.

"The IT department takes responsibility for the network, but leaves responsibility to individual users to copy data onto the network in the first place. But data often is not getting backed up," said Erik Moller, HP marketing director for infrastructure management in EMEA.

The typical cost of each data loss incident, whether owing to hard disk failure, theft or some other reason, is about $3,000 (£1,800), according to HP, which is "a major driver" for extending protection to laptops, the company said.

With the HP Data Protector Notebook Extension, users get continuous file protection "whether you are online or offline", according to Moller.

"If your hard drive crashes, the last time you were online and backed up to the vault, you can recover from this," he said.

The tool uses de-duplication technology and only transmits changes to minimise the amount of information sent back to the vault.

Administrators can set policies for which files and folders are protected, so that the contents of My Documents gets backed up, but MPG files are excluded, for example. This includes Office documents, as well as snapshots of a user's Outlook database, which can be tricky to back up because it is open most of the time.

The HP Data Protector Notebook Extension requires a client agent on each laptop and the Data Protector software and data vault running in the data centre.

The additional software is "minimal" for customers already using Data Protector, Moller said.