Wi-Fi

New paint protects wireless devices


EMC-SEC Technologies, the sales and marketing arm of Unitech LLC, announced that it will begin marketing an RF reflecting paint ("Unwanted Wireless Signals Bouce Off This Paint", W. David Gardner, InformationWeek, 16 Mar 2007). The paint is used by various U.S. defense and intelligence agencies and was subjected to three years of testing.

The paint is easy to use.  Simply roll , brush or spray it on the walls of a room or structure and wireless signals are reflected back.  This is a valuable tool to prevent eavesdropping.

There are some disadvantages that might cause adopters of this reflective paint to use it sparingly.  Anyone standing in a room with this paint on the walls and ceiling will find that their cell phones don't work.

 

About

Tom is a security researcher for the InfoSec Institute and an IT professional with over 30 years of experience. He has written three books, Just Enough Security, Microsoft Virtualization, and Enterprise Security: A Practitioner's Guide (to be publish...

14 comments
PeterSS
PeterSS

Good idea in principle, but most rooms have windows, which would let the signal in/out. Most offices these days only have glass for walls, so the paint wouldn't be much use, unless it was see-through! Is there a RF-reflective film that can be put on windows?

sharper999
sharper999

Please, paint my favorite restaurants and theaters and save us all the well-known annoyance of inconsiderate cell-phone jabberers!

glenn
glenn

CPFilms has been making such films for the military and government for 7 years and has just released the technology to the commercial market. The SD1000 provides a 35dB attentuation across the IR/RF spectrum in a nearly clear film tghat can go on any window. Great stuff!

kkopp
kkopp

I had one building that I did a wireless study in that had Aluminum based window tints in it. The Wireless AP had to be less than 5 feet from the window to get more than 2 feet away from the building.

leonard.lee
leonard.lee

is it that much of an annoyance over in the US? people chatting on their cell phones in the middle of dinner, making the whole dining experience unenjoyable? never been to the US tho.. lol would love to! =)

mjd420nova
mjd420nova

Not only could this be useful in keeping outside signals from getting in, but keeping internal signals from getting out. Now only meant to silence cell phones, but to protect wifi hot spots from outside non-customer signals getting. This could even be useful at home to keep your wifi router safe from those who wish to freeload on your connection.

Neon Samurai
Neon Samurai

The last article I saw about wifi blocking paint was while the product was still directed at military, government and big business. If the price drops to the consumer level, I may keep spraying the back yard with my router but the neibours and front yard don't need to be constantly irradiated.

glenn
glenn

Standard Aluminum based tinting does reduce the transmissions through the glass but there are big holes in the frequencies that they block leaving many access holes. CPFilms has a film SD1000 that will knock it down across the spectrum.

kkopp
kkopp

Thats why you're supposed to turn down the wireless to the lowest setting that still gets the job done. Not to mention WPA and other security measures.

Ron_007
Ron_007

I've read about active blocking/masking devices, but I thought they were illegal in public places (in some locals at least). Well a passive paint wouldn't be illegal, would it. You can just say "sorry, we must be in a dead zone (snicker, snicker)" Does it still work if covered by a more aesthetically pleasing color paint? That covers, ;-), the walls. What about the windows and doors? How significant are they for RF leakage?

kkopp
kkopp

Actually... RF studies that I did for Medtronic showed that Aluminum shades and Tinting with Aluminum in it worked wonders for blocking that frequency.

Koerper
Koerper

We're already bombarded by emf radiation from every direction, e.g. tv, radio, cell towers & phones, and a million other communication devices. It depends on your specific set up, but I doubt that the reflected energy from your own devices would exceed the energy that might be blocked.

Neon Samurai
Neon Samurai

The paint works like the shielding in your microwave to block the radio wave a-la metal shielding. You can put anything over it you like, as long as it's between transmitter and reciever. I suspect window shielding is already available for a relative price. I could see a thin metal mesh or tinting coating.

leonard.lee
leonard.lee

won't it become one of those situations where radiation stays in the same place, turning your cosy airconditioned room into a radiation plant?

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