Anti-wi-fi paint

[Zeno Swijtink]

Anti-wi-fi paint offers security
DIGITAL PLANET
By Dave Lee
BBC World Service

With a quick lick of paint, your wi-fi connection could be secured

Researchers say they have created a special kind of paint which can block out wireless signals.

It means security-conscious wireless users could block their neighbours from being able to access their home network - without having to set up encryption.

The paint contains an aluminium-iron oxide which resonates at the same frequency as wi-fi - or other radio waves - meaning the airborne data is absorbed and blocked.

By coating an entire room, signals can't get in and, crucially, can't get out.

Developed at the University of Tokyo, the paint could cost as little as £10 per kilogram, researchers say.

Cost-effective security

The makers say that for businesses it's a quick and cheap way of preventing access to sensitive data from unauthorised users. Presently, most companies have to invest in complicated encryption software to deter hackers.

Speaking on the BBC World Service's Digital Planet programme, Shin-ichi Ohkoshi, who is leading the project, explained how the paint could have many uses beyond security.

"In a medical setting, you could transmit large volumes of data from a medical device, such as an endoscope, to a computer.


You could block phone signals from outside and stop people's phones ringing during the movie.

Shin-ichi Ohkoshi, University of Tokyo

"By painting a solution containing our magnetic particles on the walls, you would quickly, and effectively, shield the room from stray electromagnetic radiation from outside."

While paints blocking lower frequencies have been available for some time, Mr Ohkoshi's technology is the first to absorb frequencies transmitting at 100GHz (gigahertz). Signals carrying a larger amount of data - such as wireless internet - travel at a higher frequency than, for example, FM radio.

"I'm working on a material that can absorb a larger range of frequencies. We are capable of making a paint that can absorb over 200 gigahertz."

He hopes that soon the technology could be woven into clothing.

"We're not sure about the true effects of electromagnetic waves, in this range, on the human body.

"We're assuming that excessive exposure could be bad for us. Therefore we're trying to make protective clothes for young children or pregnant women to help protect their bodies from such waves."

At the movies

The paint could also provide some much-needed relief during nights out at the cinema.

[Karl Frederick]

The article is a little misleading. This paint is apparently a new development in absorptive shielding technology for 100 GHz, but it's not intended for the consumer market. 100 GHZ is far above the frequency range of the common commercial and home-use wi-fi signals of 2.4 GHz and 5 GHz that are ubiquitous in urban areas. There are already paints on the market which can provide a primarily conductive (though some also claim a small amount of absorption) shield to those wi-fi (and cell phone) signals.

Anti-wi-fi paint offers security
DIGITAL PLANET
By Dave Lee
BBC World Service

With a quick lick of paint, your wi-fi connection could be secured . . . .