Slashdot Mirror
RF-Blocking Wallpaper
spitefulcrow writes "Silicon.com is reporting on a new application for RF-absorbing materials: Wallpaper that blocks Wi-Fi. BAE, the British defense contractor, has announced that the same material used to foil radar by stealth bombers can be used to selectively block certain frequencies and prevent wireless networking signals from entering or exiting a building. Is this the next take on lining the walls with lead?"
A conductive mesh layer in some wall paper.
autopr0n is like, down and stuff.
This means that you can not use WLAN, cellphones and terrestrial TV/Radio. Is this really what you want?
Quoth the article:
The company has produced panels using the technology to produce a screen that will prevent outsiders from listening in on companies' Wi-Fi traffic but let other radio and mobile phone traffic get through.
Tarsnap: Online backups for the truly paranoid
Oh how I would love that application of it in Norway. Unfortunately it's not allowed. The "problem" with this solution is that if there happens an accident - one "should" be able to call the norwegian equivalent of 911.
I think it sucks too.
"Rune Kristian Viken" - http://www.nwo.no - arca
Quite usefull for setting test environments as well. In fact, extremely useful if you are working on cellular infrastructure or any other radio equipment that operates in a licensed band.
Baker's Law: Misery no longer loves company. Nowadays it insists on it
http://www.sigsegv.cx/
Copper cables are far too easy to detect and physically tap. For really sensitive applications fibre-optic cables are used. A classic text book example being the use of fibre optics to link up scud missiles launchers in Iraq.
OpenBSD has built-in support for IPSec, so it was quite easy to setup for WiFi. The OpenBSD firewall at home is functioning as an access point, and only IPSec related/authenticated traffic is allowed. So when I boot up the older laptop - that is also running OpenBSD - I'm up and running securely. And fast, since no encryption is done on the WiFi chipset, and thus freeing the chipset for handling packets only.
OpenBSD really makes it straightforward to setup a secure, functional and stable home gateway.
* FOOTNOTE: The American spelling** of aluminum is used here. If you are searching for more information on aluminum, be aware that the British spell it "aluminium" (and pronounce it accordingly).
** HISTORICAL FOOTNOTE: Aluminum was originally named "alumium" by Sir Humphry Davy, who later changed it to "aluminum" (perhaps in an attempt to make it more Latinized since alumen is Latin for alum, the aluminum compound that the name is derived from). The British (and allied English speakers) shortly thereafter changed the name once more, this time to "aluminium" so that it would again match the pattern of most other elements (helium, sodium, etc.), while the North Americans eventually decided to keep the second, slightly more traditional name. I predict that North Americans will adopt the more regular "-ium" spelling by the year 2050, prompting the British to start calling it "alumininium". At that point debate can begin on changing "platinum" to "platinium"
;-)
There is much cruelty in the universe, John.
Yeah, we seem to have the tour map.
The FSS, or frequency selective surface, which is used in the panels described in the article works as a frequency selective filter to an electromagnetic wave. The one by the british firm is used as a stop band filter, which lets everything except WiFi-frequencies pass. It is also possible to make FSS which works as pass-band filters, usually for radar applications. (Stealth planes incorporates FSS in order to have a reflecting surface for the enemys radar, but which is still transparent for the planes own radar.)
So it is very different from ordinary aluminium foil. Foil wallpaper and window treatments have been available for quite a while, both for security applications and for people concerned about electromagnetic radiation. But these blocks all frequencies.
Reading The Fine Article is naturally out of the question, this being /., but it would have told you that the FSS (Frequency Selective Surface) panels can be applied to many surfaces, including glass. One must assume that it does not significantly deteriorate your ability to look through the glass, since it was specifically mentioned.
The pattern of most other metals, not most other elements. Every element ending in -ium is a metal except helium. The latter was first observed on the sun, via spectrometry, and was believed to be a metal, so it was named "sun metal" in Latin. By the time it was found on earth, it was too late to change the name.
rj
Wrapping the whole places in tinfoil would work nicely as well, as long as you don't leave any holes. No need to go to anything as heavy as lead, unless you're trying to block things like X-rays or gamma rays.
-ium vs -um in Latin doesn't have anything to do with the elements being metals or not. Just look at the names of the different elements and you'll see a heap of non-metals ending in -ium: Hydrogenium, Oxygenium, Nitrogenium...
while just as many, or even more, metals end in just -um: Ferrum, Cuprum, Plumbum, Hydragurum, Aurum...