Reading IM Conversations Through Walls

Russell Shaw has picked up an interesting story here:-

Quote:

U.K.-based New Scientist magazine's online tech editor Tom Simonite reports that Cambridge University computer security researcher Markus Kuhn has developed a way for a radio antenna and radio receiver to grab images off a computer screen through physical barriers.

http://blogs.zdnet.com/ip-telephony/?p=1553

Interesting ! But I am not very happy with this report and believe it to be a re hash of something that has been discussed for years in conjunction with security of CRT monitors.

I used to be involved with this element of security and there were several instances where I saw entire rooms electromagnetically screened to prohibit the possibility of screen grabs or transmission of other data by radiated means.

As far as I am aware current monitor technology using plasma and LCD uses a fraction of the voltage and energy that used to be required to fire an image onto one of the old CRT screens. For that reason the chance of picking up stray fields from any distance away by induction is almost zero.

I remember a TV programme years ago about MI5, probably in the wake of the Spycatcher book furore, where they talked about picking up CRT images from the electromagnetic emissions. The idea's been around forever, but perhaps people have been working to improve this spy technology for the last 20 years.

On the whole probably cheaper and easier to follow people and steal their laptops. I've seen reports of alarming numbers of laptops going missing both belonging to UK and US security services.