MI5 vets Tetra radio system for security

MI5, the domestic intelligence service, is to use the terrestrial trunked radio (Tetra) communications system, which is expected to be nationally available within two years.

Tetra is a digital trunked radio standard which allows users to make both mobile phone and walkie-talkie calls from their handsets for combined voice and data communications.

The agency is to use the public safety radio communications service (PSRCS), known as Airwave, which is managed by BT Quadrant. It will sit on the accreditation panel for Airwave's security.

The PSRCS project has been designed for use by public safety organisations. Lancashire Police is trialing the service.

"MI5 is very concerned about the security of the infrastructure, because using a third party for making communications leaves the issue out of its control," said Brian Williams, senior consultant at Telecommunications Consultants International.

"The entire communications system for Airwave will be accredited to a 'restricted' level of security," said Brian Murgatroyd, chairman of the security group at Airwave.

The 'restricted' level of security is the lowest level of classification in the UK.

All voice and data communications on Airwave will be encrypted at the air interface to prevent eavesdropping. Any users will be vetted before being allowed to use the system.

Questions have been raised about Airwave's susceptibility to jamming, however. "Any radio system can be jammed," said Rod Attewell, radio communications manager for Thames Valley Police.

"The Airwave system is for uniform and not anti-terrorist networks, but we are satisfied that it provides adequate security for policing operations," he added.

The communications electronics security group (CESG) will supervise the technical evaluation of the security of the Airwave network when it goes live.

CESG is part of government communications headquarters (GCHQ), the UK signals intelligence agency.

First published in Computing