Secret sub tech hints at spooks' TEMPEST-busting bugs

Through the cabbage patch - or into the secret walled garden?

BAE is choosing to emphasise the technology's uses in submarines, whose steel pressure hulls must normally have hundreds of "penetrations". Each of these is a maintenance and design burden - so much so that the pressure hull must be significantly thicker and heavier at the "cabbage patch" forward of the sub's conning tower/sail, where most of the penetrations are clustered.

Likewise such kit would make it much simpler to let soldiers inside a tank or personnel carrier see out, without compromising their armour by inserting windows or holes for camera feeds. Similarly sensors or instruments inside a reactor core or other expensively sealed environment could be installed more cheaply and conveniently.

None of these applications, though, would seem to call for secrecy regarding the mechanism by which the power and data are carried. One is compelled to speculate regarding other uses for it, which might be frustrated if enemies of the British state knew the details.

Just for instance, it's possible to imagine a bug, camera or wiretap of some sort clandestinely installed inside a building, drawing its power wirelessly from equipment outside the walls and sending its harvest of data out by the same means. Not only would there be no need for giveaway battery changes or concealed wiring; the gear would also be invisible to ordinary radio-frequency type countersurveillance scans.

And better: the BAE gear apparently works right through a ferrous steel submarine hull, so its possible spooky counterpart might just be able to drill through a Faraday cage of the sort frequently wrapped around sensitive rooms, computers or comms gear as a security measure. Such measures - for instance those required to pass GCHQ's "TEMPEST" certification - are designed to block unintentional emissions from one's own gear, usually in the RF spectrum, rather than stopping special installed bugs working on quite different principles.

Dr Kent says that BAE's kit is not yet in service, but there are other labs than BAE's in the UK. In particular the intelligence services are known to have extensive technical shops of their own, potentially well able to develop this sort of kit - perhaps some time ago, in fact.

It doesn't seem impossible that even now MI5/SS, MI6/SIS and GCHQ have equipment similar to BAE's sub/tank datalinks in the field, siphoning information undetectably out of systems or locations considered impenetrably secure by their owners. It also seems plausible, given the request from "other government parties" that BAE not reveal details of their gear, that there is some way to frustrate such methods once you know about them.

The world of bugging and clandestine surveillance - and countermeasures against these - may be about to suffer another technical upset in the near future. ®