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Wireless Networking Hardware Technology

House Paint Foils Wardrivers 444

Ant writes "Security-minded U.S. decorators' supply outfit, Force Field Wireless, claims to have developed a do-it-yourself solution to the international menace of marauding geek wardrivers: DefendAir paint 'laced with copper and aluminum fibers that form an electromagnetic shield, blocking most radio waves and protecting wireless networks.' According to the South Florida Sun-Sentinel's report, one coat of the water-based paint 'shields Wi-Fi, WiMax and Bluetooth networks operating at frequencies from 100 megahertz to 2.4 gigahertz", while two or three applications are 'good for networks operating at up to five gigahertz.' However, there are downsides to this." Since it's a water-based paint, exterior use is only recommended for people who want more copper and aluminum in the soil surrounding their house.
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House Paint Foils Wardrivers

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  • by drgonzo59 ( 747139 ) on Friday January 14, 2005 @01:56AM (#11358098)
    Would you have to climb up the chimney to call your friends?
    • Does your phone operate at frequencies from 100 megahertz to 2.4 gigahertz" ?
    • Oddly enough, I can envision this product appearing in schools. It would suppress the "distraction" of text messaging.
      • Or perhaps in movie theatres, but then jamming would be easier than painting I think. Also, doctors or any person who has to be on-call might object to that.
        • I object to the on-call people being in movie theatres. Go see the frickin' movie on the night when you're NOT on-call.

          I'm all in favor of jamming cell phones in theatres. Patrons are already far too noisy and rude, and cell phones have not helped.

          • by rsidd ( 6328 ) on Friday January 14, 2005 @03:07AM (#11358670)
            I object to the on-call people being in movie theatres. Go see the frickin' movie on the night when you're NOT on-call.

            I like the way some people assume doctors are not allowed to have a life. It's ok to call the doctor whenever you like, day or night, but it's not ok for the doctor to go out and watch a movie? The doctors I know leave their phone on vibrate, sit at the back of the theatre, go out to answer a call (more often it's an SMS which they can answer sitting where they are). Exactly what's wrong with that?

            • I don't really have anything to say, I just thought you might like a reply that wasn't troll or flamebait.
          • "I'm all in favor of jamming cell phones in theatres."

            I seem to remember hearing something about them doing exactly that, like in Europe or something...
          • by stuartkahler ( 569400 ) on Friday January 14, 2005 @04:19AM (#11359123)
            I object to the on-call people being in movie theatres. Go see the frickin' movie on the night when you're NOT on-call.
            Some doctors are pretty much on call 24/365. If you're the only [FOO]ologist practicing within 200 miles, you take calls whenever someone has a question. I'm not talking about small towns in the middle of nowhere either. There are lots of subspecialties that only have one practicing doctor serving a population base of millions.
            Not that they're the problem. It's the teenagers who thing they're some kind of socialite and can't wait an hour to find out who dumped or hooked up with who. Or even worse, the idiots who think that having a cell phone makes them part of the elite, and they spend every waking moment showing it off.
            Theaters who really care would post notice that they kick out people with ringing cell phones. No refund. Then follow through.
          • by kaustik ( 574490 ) on Friday January 14, 2005 @12:27PM (#11362653)
            Some of use are on call 24-7. For example, I carry a Blackberry where I get messages related to things like dropped pings on a critical production server. The Blackberry is always on vibrate, and I doubt that the slight buzz would even be heard by anyone in the theater. At that point, I can decide whether or not I need to leave, or at least begin to plan what I will do when the movie ends. If I do decide to leave, I am no more of a bother than the tons of people getting up to piss every 15 minutes.
            I would purposely avoid movie theaters that blocked my signal.
        • It's still illegal to jam cell phones in the U.S., isn't it?
      • But schools allow students to use mobile phones outside of lessons, and the teachers need to carry them.
        • WHY do teachers NEED to carry cell phones? And even if that was the case, they could be wearing simple wireless phones connected to the landbased phone system, the signal should stay within the building...

          I had other things in mind though. All those people who are afraid of the new 3G frequencies and the problems that can cause, can we simply not paint their houses?

          Or this discussion we had a while back about amish people not allowing cell phones. What a great opportunity for them.

          So, the last question i
    • by Anonymous Coward
      Would you have to climb up the chimney to call your friends?
      Climb up the chimney? You could just walk outside. You don't have pointy-hair perchance?
    • by goombah99 ( 560566 ) on Friday January 14, 2005 @02:54AM (#11358591)
      This could also create problems too. past studies have noted that cell phone intenisty inside subway carriages can be 100 fold higher due to resonant trapping of the energy. Edge effects could be even higher. Like wise there will be reflections creating nodes in your house. Since the wavelengths are quite long these nodes will be macroscopically large.

      Notably, the corners of your house will act like corner cubes maximally reflecting the energy back to the emitter itself. If the emitter happens to be your laptop then you are going to get the majority of the radiation passing through you on each round trip bounce.

      as it happens, the wavelength is near the wavelength of your microwave. The microwave is tuned to optimally excite the rotational frequency of aqueaous water. The 2.4 Ghz is slightly off the optimum but You are inhogenous enough that you probably absorb quite well in this region. The rest of the dry materials in the room wont be doing much absorbing. Thus you will become the primary fate of all the radiated energy.

      so you lose on two accounts: 1) high field strengths 2) all the energy resonates around till if finds your testicles.

      • Not everyone has inconsiderate clod!
      • The microwave is tuned to optimally excite the rotational frequency of aqueaous water.

        Er, no it's not. Microwave ovens radiate at about 2.3-2.4 GHz, but the resonant frequency of water which that affects is about 10 GHz. The suboptimal matching means that microwaves penetrate food, rather than flash-boiling the outside layer and leaving the inside raw.

      • I thought folks at /. were supposed to know at least a little science. Microwaves send out waves with power on the order of several HUNDRED WATTS (or more). The wireless antenna in your laptop is about a hundred MILLIWATTS. Both signals are at 2.4GHz, the same as a domestic microwave oven. So right there we are talking 1000+ fold less intensity of signal. Then there is the distance factor. Radiation declines as the square of the distance from the source - so if you move from 1 foot to 2 feet from the ante
    • by maxwell demon ( 590494 ) on Friday January 14, 2005 @03:39AM (#11358892) Journal
      I've heared rumors of a revolutionary invention which could relieve you from climbing up the chimney. It's called fixed line phone.
    • Damn. What kind of house do live in? Or did you just paint the doors and windows shut, too, for extra NSA-quality security? :)
      • IR shielding on more expensive glass does it already. Painting the doors is also a bloody good idea and I have alluminized floor underlay already (saves you up to 20-30% of heat loss through the floor). T

        Actually, they are marketing it the wrong way. They are marketing it as means of signal not getting out. I think the case of signal not getting in is considerably more interesting.

        Which leads to the nice and obvious results. The idiot neigbour with the new and flashy access point he got for Xmas is no lo

  • Dupe (Score:5, Informative)

    by BenFranske ( 646563 ) on Friday January 14, 2005 @01:57AM (#11358108) Homepage
    This story was already covered here []
  • Stop the presses. (Score:2, Insightful)

    by koreaman ( 835838 )
    A new, better solution has been developed. They call it ENCRYPTION!!! Oh how wonderful. Now we don't even need to repaint our houses.
    • En..cryp..tion..? What is this newfangled devilry?!
    • Yes! Because WEP was Soooooo and it's wacky old 24 bit init vector.

      If you're going to be sarcastic, at least be more specific.
      • Why, so he beat any humor an irony right out of the discussion?

        Maybe he means WPA or RADIUS, or even WEP, possibly with MAC restrictions and strong passwords. Maybe he means running everything through ssh tunnels on his wide-ass open wireless network.

        Why would encryption equate with WEP necessarily?

    • However, in areas, i.e. apartment buildings, this paint would be extremely useful. In some apartment buildings there are too many WiFi access points. A paint like this could help people to prevent problems with comflicting signals -- in otherwords you keep your signal in, but you can also keep other signals out, thus reducing interference. The paint has far more implicications in protecting wireless technologies as well as keeping wireless out. University testing centers could use it to insulate a room agai
  • Dupe (Score:2, Informative)

    Found by searching Slashdot for "paint". 12 8253&tid=193&tid=172&tid=218
  • Neal, you're dumb (Score:5, Informative)

    by Anonymous Coward on Friday January 14, 2005 @01:58AM (#11358127)
    Just because it's water base doesn't mean it will wash away with water. Latex paint is water based... Once the water evaporates the emulsion hardens.
    • Re:Neal, you're dumb (Score:2, Informative)

      by amerinese ( 685318 )
      Sort of. It also peels, cracks, powders and gets washed back into the soil. Neal may have made a poor implication that only water-based paints would leak particulate into the soil, but exterior paint will still go into the soil. Which also probably means that adding metals to make your own paint mix is either illegal or environmentally dangerous enough that it should be illegal.
    • Is aluminum and copper in the soil actually a bad thing? I thought those metals just passed right through us. After all, we do use aluminum foil on our food and we move drinking water through copper pipes. Aluminum is fairly reactive and easily forms aluminum oxide, which, if I remember correctly, is a noteworthy portion of ordinary clay. Please correct me if I'm wrong on any of these points.

      I know they're looking to improve convenience, but I think someone should say one more time for the late arrivals:
  • It is a DUPE [] from LESS then TWO weeks ago.

    Honestly, do the "Editors" not even read the site?

    I know it's probably always been like this around here...but still.

    On another note, did anybody else notice that /. was down for a few hours earlier today?
    • Parent post is a DUPE [] from LESS than TWO minutes ago.

      Honestly, do the "Posters" not even read concurrent posts?

      I know, it's probably always been like this around here...but still.

      On another note, :-p
    • On another note, did anybody else notice that /. was down for a few hours earlier today?

      Yes, at least an hour of Internal Server Error. Same with newsforge.
  • wow... (Score:5, Funny)

    by Anonymous Coward on Friday January 14, 2005 @01:59AM (#11358140)
    they make tin foil hats for houses now...
  • Whatever... (Score:5, Funny)

    by A Boy and His Blob ( 772370 ) on Friday January 14, 2005 @01:59AM (#11358143)
    Paint your house with this stuff? Psshh, I take care of the SOURCE of the problem, I shoot war drivers with my paintball gun.
  • by aardwolf204 ( 630780 ) on Friday January 14, 2005 @02:03AM (#11358167)
    My dad was a war photographer in Korea. He had some level of clearance and once was working at a base on the coast of Florida photographing experimental weapons. He was walking around the facility and started talking to a major. The major was complaining about the fishing boats close off the coast, saying that they were known communist spies doing surveillance of the bases secret operations. The nature of the operations made them need to be outside and there was not much they could do about keeping the spies from photographing their operations from the fishing boats.

    My dad suggested that they build a pipeline around the base and pump extremely hot water through it. The steam would keep the spies from getting clear photographs of the bases operations.

    Ever been to the airport and notice that distortion coming off the top of the jets in the summer? The waviness is caused by the steam and heat coming from the plane. This is the basis for the pipeline.

    The major had the pipeline constructed and shortly after the fishing boats stopped snooping around the base. Think of it as a photographic firewall...

    Its not that OT when you think about it.
  • How useful! (Score:3, Insightful)

    by Myrkridian42 ( 840659 ) on Friday January 14, 2005 @02:03AM (#11358168)
    This is great, unless you YOURSELF want to connect from the outside, like from your backyard.
    • This is great, unless you YOURSELF want to connect from the outside, like from your backyard.

      This is great, unless you YOURSELF want to dump a bunch of toxic paint into your backyard.

  • Dupe (Score:3, Funny)

    by complete loony ( 663508 ) <> on Friday January 14, 2005 @02:05AM (#11358194)
    (sung to the tune of the popular song "Gold Gold Gold Gold")
    Dupe Dupe Dupe Dupe
    Dupe Dupe Dupe Dupe
    Dupe Dupe Dupe Dupe
    Dupe Dupe Dupe Dupe
  • I'm glad I can secure my wireless network...and also effectively stop my radio, mobile phone and 2-way radios too.

    The best part is when the wife takes the cordless phone outside...second she shuts the door, DISCONNECTED! This would be a great Valentine's Day networks, but no phone.

    Oh wait...that's okay honey...we'll get VoIP (on a wired phone) and we have internet radio. What? Divorce? Don't touch that's impor
  • Interesting... (Score:3, Interesting)

    by gardyloo ( 512791 ) on Friday January 14, 2005 @02:05AM (#11358197)
    I'm not really familiar with wireless technology, but I DO know that a conductive shield around something will protect the thing inside it from extraneous electrical fields (as long as their frequency isn't super-high), but that any radiation produced by the thing inside the conductive shield will get out just fine. Because wireless things are on carriers of "only" several GHz, the increased size of the shield (as opposed to the normal antenna or whatever) shouldn't make any difference to phasings.
    I guess that most people have their houses land-lined (or satellited, or whatever), and then use wireless networks to distribute bandwidth _within_ the house, right? Because putting a shield around such a house would only serve to keep outside signals from getting in, not inside signals from getting out. Of course, if protocols usually work with a "give-and-take" system, then this would cut off part of that, and people wouldn't be able to connect to your wireless system, but they _would_ be able to eavesdrop.
    • I DO know that a conductive shield around something will protect the thing inside it from extraneous electrical fields (as long as their frequency isn't super-high), but that any radiation produced by the thing inside the conductive shield will get out just fine.

      And in this strange universe you apparently inhabit, how does the conductive shielding know which side is "in" and which is "out", so that it can pass the electromagnetic radiation in only one direction?

      Shielding that does that would have the

      • Re:Interesting... (Score:3, Interesting)

        by gardyloo ( 512791 )
        It's not difficult at all. An electrical conductor will rearrange its free charges so as to make the potential within it a constant, and (+/-, depending on your gauge definition) grad(potential) gives your electrical field: thus, no field within an *empty* cavity within a conductive shield. (Can also be shown from Gauss' Law, and integrating around any closed loop which partially goes through the cavity, and partially through the conductor.)
        However, if you introduce some non-zero field into the cavity (
        • If the field is produced inside of the conductor, explain to me exactly how it can emit without having a field line crossing through the conductor?

          A shield broken by a wire is not a closed conducting surface, by the way, making your example completely outside the question, which is - how does a closed conducting shell know the difference between inside the shell and outside the shell? (Answer: it doesn't, and a *completely* closed conducting shell is a perfect shield for EM radiation).
    • Re:Interesting... (Score:5, Informative)

      by plover ( 150551 ) * on Friday January 14, 2005 @02:18AM (#11358303) Homepage Journal
      Umm, no. Faraday cages are bi-directional. They block EMF in either direction.

      For proof, go stand in front of your microwave oven with the door closed, heat a glass of water for a minute, then go reproduce. If your children are born with n arms, where 1 < n < 3, the EMF was blocked.

      • Re:Interesting... (Score:2, Interesting)

        by Anonymous Coward
        For a mathematicians version of this proof, consider this: when you paint your house in laced paint, are you enclosing your house or the rest of the universe? =) The two are equivalent, and hence, if you're transmitting from inside your house, you are *outside* the protected universe, and your signals can't get there.
      • My kid's got 1.5 arms, you insensitive clod!
  • by digitect ( 217483 ) <`digitect' `at' `'> on Friday January 14, 2005 @02:06AM (#11358212)
    This seems also to be an ideal product to increase the chances of your house being struck by lightning, too.
  • by Krankheit ( 830769 ) on Friday January 14, 2005 @02:10AM (#11358238)
    How will you cover areas such as windows? If this doesn't cover the windows, war drivers are not foiled.
  • Now do I change the defaults on this linksys, Or just repaint the house. Hmmmmm cost of copper in wiring up the house compared to cost of wireless networking and plastering the entire house in copper, its a tough call. Manual pls.
  • by ZiZ ( 564727 ) * on Friday January 14, 2005 @02:32AM (#11358417) Homepage
    I love this stuff! I use it all the time to paint my tin-foil hats to look more like hair. You know, like in Calvin and Hobbes.
  • Considering that Water Based doesn't mean water soluable (Consider that all acrylic latex paints are pretty much all Water Based- which is the likely base for this stuff...) it's kind of silly to say that it's going to increase the copper and aluminum content of your soil as it's largely not going to wash off in the first place...
  • Anyone else smell a law suit? Oh, you can't smell? Or breathe? Must be the laced with copper and aluminum fibers paint you've just smothered the babies crib and the inside of your house with. Does anyone else think this crap just wreaks of a law suit? Or are we all disoriented and stricken with alzheimers due to the aluminum and copper laced paint chips we just unknowningly ate with our cherrios?
    • by dbIII ( 701233 ) on Friday January 14, 2005 @03:25AM (#11358801)
      Or are we all disoriented and stricken with alzheimers due to the aluminum
      Here's an interesting bit of trivia about the early alzheimers research: it compared fresh brains from a control group with brains of sufferers that had been preserved in an aluminium sulphate solution. For years people were trying to work out how we could possibly metabolise aluminum (it take serious chemicals, heat and electricity to extract it from alumina) until someone took a look at the orginal study and tracked down the contaminant.

      The more stupid the mistake the less people want to admit it - it took many years before aluminium was ruled out as a contaminant, but since the aluminium link had been in the newspapers for years we are stuck with another urban myth (just like the wartime carrot nightsight myth - you can't magically boost you night vision with carrots (Mawson didn't get better vision fron a near lethal dose of vitamin A), but it was the excuse to avoid admitting that radar existed in WWII).

  • Not only will this block Wi-Fi, but it will also block cell phone communications [] as well. Of course, some may appreciate the paint's second use as a cell phone blocker!
  • by ForestGrump ( 644805 ) on Friday January 14, 2005 @02:48AM (#11358548) Homepage Journal
    But atleast I don't have to worry about my 802.11b/g network being hijacked.

    I live in a house with lead paint.

    no, just kidding.
  • Conductive surfaces don't block RF much unless they're grounded. Wire mesh is effective if the joints are electrically bonded, which nobody does in ordinary construction. Otherwise, it's useless.

    Anybody who has been involved with RF-tight enclosures or rooms will realize this. You need solid metal all the way around, with RF-tight gaskets at openings.

    If you can receive any radio signals inside your "shielded room", it's not shielded.

    • electrical bonding is done in all steel reinforcement in the concrete for about 3m around a swimming pool.

      In a prison I was involved in the design of, there was some discussion (subsequently dismissed) of introducing a "leaky wire" into the reinforcement to generate noise to prevent inmates using phones to plan crimes. The thing that scuttled it was the worry that the guards might need to use their own phones to call for help if their radios failed them
  • Wi-Fi Finder Plus (KEN201)
    Find wireless networks instantly. Just press a button and the Kensington Wi-Fi Finder lets you know if your location is "hot" instantly. Learn more


    So I'd like to see how biased their Wi-Fi Finder is with their paint.

    Kinda like puttin the ol' Humidifier and De-Humidifier in the same room.
    But if your my Humidifier, then lets give ya break on the De-Humidifying.

    (shameless advertising /. overlords. ;)
  • at the end of the day if you really want security use a piece of fibre or stp and make sure you can see the cable from point to point so you know there are no taps.. then turn your computers off..
  • ... radio? television? mobile phones? pagers?

    That's a pretty broad frequency spectrum which they are messing with ...
  • Firstly install a wifi node called linksys. Let them get to the "internet" through it, quite freely.
    Next step is to put a linux machine between that and internet in a way that it doesn't look to outside word as anything, it forwards packets to internet gateway as it would of been from the wifi directly and same thing counter clockwise. With few exceptions. It creates packets that look that they come from internet site X running an assault to wardriver. Pick IP address that is assigned to goverment for such
  • I don't suppose they expect people to paint over their windows! So... this tin-foil coating (almost literally) isn't going to be perfect.

    Bah! Encryption is the only way to go anyway. What happens when you have people, say, come inside your house? Never mind the inconvenience of no cell-phones.

    I guess there are some niches for this product...somewhere.
  • Oh, you mean that ubber-fancy geek cordless landline telephone you have no longer works outside the home? That's ok. Geeks don't get much sun anyways.

    Oh darn. You 800 and 1900Mhz CDMA cell phones no longer work inside? Guess you'll have to go outside. Whoops. There's that sun vs geek factor again.

    Gee, your pager doesn't work inside either? Your employer wouldn't require you to wear one, would they?

    Having trouble with your garage door opener? Guess you'll just have to get out of the car and pus

  • insulated walls (Score:3, Interesting)

    by pair-a-noyd ( 594371 ) on Friday January 14, 2005 @04:10AM (#11359073)
    My dad insulated the walls of his garage with Styrofoam with a foil backing. His 900mhz phone doesn't work in the garage now.
    He tried running a wire from inside the garage to outside of the garage thinking it may carry the signal, but that didn't work very well.
    He tried moving the base station to the upstairs of the house but the sheet metal roof blocked it from that angle too.

    MOST new homes are now constructed (around here) with that foil backed styrofoam. Seeing the trouble it made with a 900mhz phone, I would think it cause just as much trouble for other signals. It's solid so I would think no wavelength should be able to penetrate it except by sheer brute force, IE a "hot" signal.

  • by stuartkahler ( 569400 ) on Friday January 14, 2005 @04:50AM (#11359297)
    Even if you thought it was worth it to prevent your neighbors' wifi from interfering with yours, it's still stupid. You kill your cell phone reception, probably reduce your TV reception, and it's impractical to paint your ceilings, floors, windows, doors and fireplace. It's expensive to apply, and can't be removed easily, so when you go to sell nobody wants the property. For all the costs and effort, you can hire someone to wire ports into every room in your house. Or put repeaters in every room. Painting every surface of your home to get good wifi is asinine.
    If I did work somewhere that was sensitive to electronic espionage, I'd have rooms built to spec with actual faraday cages and other countermeasures, not modified as an afterthought.
    • Don't knock it... something like that would be ideal for coating the insides of tents etc. to quickly create "secure" processing areas. And if anybody's wondering about patenting that idea... forget it... it's already patented. My brother holds a patent for doing that very same thing with his own special goop...
  • by Nice2Cats ( 557310 ) on Friday January 14, 2005 @09:39AM (#11360608)
    If the geometry is right (that is, if the outside wall of your house doesn't reach right up to the street), why doen't you buy a good WiFi access point so you can limit the range instead? Even Apple's Airport Express lets you do that. We've cut the signal strength to 50%, and instead of potentially giving half the neighborhood access, it is limited to our living- and bedroom (don't ask).

    I mean, that can't be more expensive than painting your whole house, can it?

In 1869 the waffle iron was invented for people who had wrinkled waffles.