The pocket-sized digital music player, which can store thousands of songs, is one of a series of banned gadgets that the military will no longer allow into most sections of its headquarters in the UK and abroad. 

Devices with large storage capabilities - most notably those with a universal serial bus (USB) plug used to connect
to a computer - have been treated recently with greater suspicion
by government agencies and corporations alike. 

The fear is that the gadgets can be used to siphon information from a computer, turning a seemingly innocuous device into a handy tool for data thieves. 

"With USB devices, if you plug it straight into the computer,
you can bypass passwords and get right on the system," said RAF Wing Commander Peter D'Ardenne.

"That's why we had to plug that gap," he said, adding that
the policy was put into effect when the MOD switched to the
USB-friendly Microsoft XP operating system over the past year. 

Virus carrier  

In a survey of 200 mid-sized and large UK companies
conducted by British security software firm Reflex Magnetics, 82% of respondents said they regard so-called mobile media
devices, including the iPod, as a security threat. 

iPods can also introduce computer viruses to a corporate network.

As a result, a small but growing number of firms, particularly those in the financial and health-care sectors, are devising policies to keep them out of their offices, said Andy Campbell, managing director of Reflex Magnetics. 

"Oftentimes, a business has no idea if an employee is stealing data via removable media," Campbell said. 

The findings reflect another report a week ago in which technology consultancy Gartner Inc advised companies to consider banning the devices because they can also unwittingly introduce computer viruses to a corporate network. 

"A portable media player with two gigabytes of capacity
could easily store a customer database. And quickly," said
Campbell.