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Newly Declassified Window Film Keeps Out Snoops

Posted by kdawson on from the pricey-tinfoil-hat-for-your-house dept.

An anonymous reader writes to describe a newly declassified window film from CPFilms Inc. that could give war drivers fits. Scientific American has the story, which includes a rather dismissive comment by Bruce Schneier. "Once manufactured under an exclusive contract with the US government, this recently declassified window film is now available to the public. But don't expect to see it on store shelves anytime soon. Currently, it's only available directly from the manufacturer, and at prices that will likely make it prohibitive for all but the wealthiest home owners. The two-millimeter-thick coating can block Wi-Fi signals, cell phone transmissions, even the near-infrared, yet is almost transparent... It can keep signals in (preventing attempts to spy on electronic communications) or out, minimizing radio interference and even the fabled electronics-destroying electromagnetic pulse generated by a nuclear blast."

51 of 193 comments (clear)

  1. War Drivers by nonsequitor · · Score: 4, Funny

    Nothing to see here, move along.

    1. Re:War Drivers by RuBLed · · Score: 3, Funny

      I believe these window films are tested enough, a crash would probably be the fault of a bad war driver.

    2. Re:War Drivers by sokoban · · Score: 5, Funny

      War Drivers? Huh, yeah. What are they good for? Absolutely nothing now.

      --
      09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0 is the magic number.
    3. Re:War Drivers by kimvette · · Score: 2, Funny

      A rocket launcher is not the kind of war driving they are referring to! ;)

      --
      The Christian Right is Neither (Christian nor right). See: Matthew 23, Matthew 25, Ezekiel 16:48-50
  2. Like they said in the good ol' days.... by madbawa · · Score: 4, Funny

    ...all your signals are belong to us.

  3. Does it come as hats? by Buchenskjoll · · Score: 5, Funny

    I would like the get rid of the tin foil ...

    --
    -- Make America hate again!
    1. Re:Does it come as hats? by mythar · · Score: 4, Funny

      Whoa, hold on there! The article doesn't say anything about blocking mind-control rays. of course it wouldn't; that information is still CLASSIFIED. I wouldn't be surprised if this stuff actually enhanced all the mind-control rays coming out of The Pentagon! neither would i, my friend. neither would i.

  4. What about the walls? by d12v10 · · Score: 5, Insightful

    I don't know much about radio signals, but what about the walls and paneling? Can they get through that?

    1. Re:What about the walls? by phatvw · · Score: 4, Interesting

      Walls tend to attenuate EM radiation much more than windows. If a building has a metal frame, which any secure building should, then it is already reasonably secure everywhere except the windows.

      Incidentally, the original article is down - slashdotted, already?. Does this tech work via the Faraday cage principle similar to the mesh on your Microwave oven view window?

    2. Re:What about the walls? by arivanov · · Score: 4, Informative

      They can, but you can use foil there. In fact if you have a modern enough house it is likely to have foil in the external wall insulation. Same for the roof. It is also trivial to retrofit (you can just lay it under a plasterboard.

      As a result the doors and the windows remain the sole way in and out for the radiowaves. While special films like the one described in the article can deliver a nearly perfect insulation, they are not necessary.

      If what you are bothered about are script kiddies driving down the street (or in your neigbour's basement) or interference from your neigbour's AP standard K-glass (or similar IR reflective type) will do. In my previous company we did a survey prior to moving into a new office and the drops was by more than 30db in the 802.11b/g band (in layman terms from 95% "quality" to sub 5%). In fact the drop from K-glass was more than the drop through a concrete floor covered by a steel plated grounded raised floor.

      --
      Baker's Law: Misery no longer loves company. Nowadays it insists on it
      http://www.sigsegv.cx/
    3. Re:What about the walls? by hughk · · Score: 2, Informative

      A rebar wall makes a fairly good Faraday cage, but mostly only the pillars are rebar. Many recent office buildings have 100% glass walls. The film would work ok there. On a building with walls, then a lot of signal normally leaks through. Yes, the posters are right in that thicker walls tend to attenuate better but usually they are quite transparent to RF.

      The thing is that at least one of the existing metallized films (3M, I think) used for solar attenuation is quite a good RF blocker. Mobiles certainly don't work through it.

      --
      See my journal, I write things there
    4. Re:What about the walls? by Andy+Dodd · · Score: 2, Informative

      I was going to comment that there are already quite inexpensive and effective window films that block RF quite well.

      That said, it seems that the big difference between them and this "declassified" one is that it seems to be optically transparent? If you don't need full optical transparency but a darkened tint is acceptable (probably not only acceptable but desirable in many office environments), metallized window tints such as even the cheapo ones sold as aftermarket automotive films will block RF quite well.

      For optically transparent - the same conductive coating used for LCD screens would probably block RF well, but that isn't a flexible "add on" film and might be prohibitively expensive for building windows, even when compared to this new stuff.

      If you don't need optical transparency, blocking RF is reasonably easy, at least for a building.

      --
      retrorocket.o not found, launch anyway?
    5. Re:What about the walls? by Lumpy · · Score: 4, Informative

      Several places make "magenetic paint" you can buy it at home depot. Paint your outer walls and ground it (copper strip going to water pipe below painted over works great. (grounding leeches off EM fields so help reduce reflections and overall background noise.)

      voila, no wifi or cellular.

      Using a special expensive window film is silly, replace your screens with aluminum screens and magically they also no longer pass RF energy.

      I get a kick out of all this "new" stuff coming out. Anyone that owns a home that was re-sided in the 70's and 80's typically has aluminum siding and aluminum screens and therefore is mostly living in a faraday cage. (except roof)

      Most of the new metalized layers on new construction materials (if any is used) dont block RF worth a darn. I tried them all at new construction sites and none were as effective as good old aluminum sheeting and screening.

      --
      Do not look at laser with remaining good eye.
    6. Re:What about the walls? by crossmr · · Score: 2

      Funny. I drive around my city (population over 1 million) and see plenty of big houses with large windows. not everyone in the world is packed in to tight town houses row by row. People like to be able to see out of their windows around here. A window that is stuck shut and a window cannot be opened are two different things. For the windows that do open, the screen is only on the part that opens, like one of those 2 parters where the bottom lifts up. Why you'd cover non-moving glass is beyond me. That's got nothing to do with upkeep and all to do with pure idiocy. It ruins your view, serves no functional purpose, and is a waste of materials and money. What's a picture window got do with birds? I see plenty of apartments that have glass in them with no screen over the glass too.

      You know what's even better? Go nuts finding lots of houses in your city without screens covering every square inch of window:http://images.google.ca/images?hl=en&q=Minn eapolis+house&btnG=Search+Images&gbv=2

      I found at least 3 on the first page.

  5. yeah, but.... by Raptoer · · Score: 4, Interesting

    "minimizing radio interference and even the fabled electronics-destroying electromagnetic pulse generated by a nuclear blast."

    yeah, but what about the walls? will the walls block it? if not then this stuff is not useless, but not as effective as one would imagine. not to mention that if a nuke went off I think we would have more problems than some EM pulse coming in through the windows...

    Just make your house into one big Faraday cage, but what about the chimneys?

    what I'm trying (and probably saying) is that you plug a hole, the waves will go through another. (not saying that we shouldn't plug them, just that we can't really stop until it is all sealed, in which case you live in a bubble.)

    1. Re:yeah, but.... by posterlogo · · Score: 2, Interesting

      that and the fact that nothing practical is really bullet proof (pardon the pun). a strong enough EMP will get through this window coating.

    2. Re:yeah, but.... by AP2k · · Score: 2, Interesting

      Even Faraday cages have their limits. Presumably, you would already have aluminum insulation or a faraday cage within the walls.

      However, there is no conceivable way that a plastic film embedded with any sort of thin, transparent conductor will be able to hold back a nuclear EMP blast. I'd hate to be standing next to it and then suddenly be covered with molten, burning plastic. Although I do suppose a nuke going off within a few hundred miles is a tad more important than immoliated.

      Lazy, none physics-knowing editors...

    3. Re:yeah, but.... by Magada · · Score: 2, Insightful

      Goes to show just how much you know about nukes and EMP.

      --
      Something bad is coming when people are suddenly anxious to tell the truth.
    4. Re:yeah, but.... by gujo-odori · · Score: 5, Informative

      Can't blame the editors. The claim regarding resistance to EMP is a direct quote from (the ad copy embedded in the middle of) TFA. Morever, what TFA has to say about the film and EMP is that it is "capable of minimizing radio interference and even...EMP." They don't say block it, they say minimize it. The effective frequency range of the film is 10 Hz. up to "just shy of visible light" so I'd say they at least have a shot at it.

      Now, EMP is what, again? Oh, yeah, Electro-Magnetic Pulse. Put another way, a really, really strong blast of RF interference. Anything that can completely block cell phone and wifi signals will at least somewhat hold back EMP. TFA goes on to say that one of the things that makes the film so effective is that it's part of a completely package. The film is only one component of what you're buying. Sounds like they probably retrofit the building with some kind of Faraday cage-like gear.

      EMP doesn't melt plastic, it fry's electronics. Well, if you were so close to the hypocenter that the EMP could melt a 2 mm plastic film on the window, that would be the least of your problems, because if you didn't get vaporized at about the same time, the shockwave that arrived shortly thereafter would blow you, the window, and maybe the wall to the other side of the room.

      The EMP they are trying to guard against is the high air burst kind (think huge warhead detonated in LEO over the US east coast) which is intended to take down electrical grids, telephone networks, and as much of everything else electronic as it can. A lot of Soviet (and presumably now Russian) scenarios included such an air burst as an early shot. Get one of those in position undetected and detonate it and you're then in a position to do a couple of things, such as:

      1. Get the other side on the hot line (if it still works, anyway) and tell them "We know we blew your comm capability and you have two minutes to decide to surrender or not
      2. As soon as it detonates, launch a first strike to make sure. If you sufficiently damaged their command and control systems, they won't get many, if any, shots off before your warheads hit their ground-based nuclear assets at the same time your hunter-killer subs are engaging their boomers wherever they can find them

      If you have your buildings protected to the best possible extent by EMP shielding such as that stuff, it might allow you to launch in such a scenario before the other side does. You'd pretty much have to, because the EMP would fry the recon sats that would normally tell you if they were launching or not. You'd have to assume they were.

    5. Re:yeah, but.... by AP2k · · Score: 3, Insightful

      Great, so neither one of you know about inductance? http://en.wikipedia.org/wiki/Electromagnetic_induc tion

      I dont suppose you would be someone to think that shorting some 20 gauge wire in an electrical socket won't vaporize the wire? Why dont you try picking up a physics book or doing some experiments yourself before commenting on a topic which you obviously do not understand?

      This isn't magic, for fucks sake. A film of plastic doesn't block out magnetic fields of any sort without being even slightly conductive.

    6. Re:yeah, but.... by Secrity · · Score: 2, Informative

      Good post on EMP, although I disagree on the vulnerability of military electronics and telecommunications to EMP.

      EMP was a known threat during the cold war and military electronics were designed to withstand EMP.

      I worked as a technician for AT&T Long Lines during the cold war and saw what was done in order to minimize the impact of EMP on the telephone facilities that were used by the military. As an example, the L-3 long haul coaxial cable system that went from Dranesville,VA and Waldorf, MD to Mojave, CA; with an L-1 spur to NORAD in Cheyenne Mountain, had tube type repeaters. Everything was heavily shielded and the facility offices and repeater manholes that were along the route were shielded underground buildings that were designed to withstand nuclear attack; including EMP. The buildings that housed AT&T AUTOVON military telephone system switches were also in those shielded underground buildings.

      EMP was a MAJOR consideration and EMP resistance was built into electronic equipment and systems. I have a very difficult time believing that recon satellites were not designed with EMP resistance being a major priority.

  6. Should have better defined "film" by The+Orange+Mage · · Score: 5, Funny

    I spent part of the article thinking, "big deal about the price, someone will just torrent it and that'll be that."

    1. Re:Should have better defined "film" by Anonymous Coward · · Score: 2, Informative

      Also, putting it under the "Windows" category is a terrible pun...

  7. Cinema Wallpaper by Anonymous Coward · · Score: 5, Insightful

    If They could make it into a wallpaper they could apply it to the inside of cinemas so assholes will not sit next to you and text people through the entire film.

    1. Re:Cinema Wallpaper by Opportunist · · Score: 4, Interesting

      That's what noisemakers are for. A cute little handy device that fills the relevant frequencies with static. Sure, they're illegal here, but they are near impossible to find and provide you with a full film without any cellphone based interruption.

      --
      We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
    2. Re:Cinema Wallpaper by Alterion · · Score: 2, Informative

      they're illegal for good reason because they block emergency calls aswell :(. If only the ambulance service had a separate frequency

    3. Re:Cinema Wallpaper by Opportunist · · Score: 2, Interesting

      First, the "wallpaper" would too. And second, there's nothing wrong with using the payphones in the lobby for an emergency call. They do work without money for emergency calls. Not to mention that it's certainly a no-brainer to turn the screamer off when someone needs to make an emergency call.

      --
      We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
    4. Re:Cinema Wallpaper by ColdWetDog · · Score: 4, Insightful
      Hey genius, what about receiving an emergency call? Does your magical device know to turn itself off when one of my loved ones was just rushed to the hospital? Or is you seeing Transformers uninterrupted more important?

      This is an interesting theme that pops up every time this sort of discussion takes place. I sometimes get the idea that the entire populace is just shivering with dreaded anticipation - waiting for that fateful cell phone call or text message to tell them that some horrible accident or disease has descended upon family or friend. That if they are out of contact for mere moments, they will live the rest of their lives in anguish because they failed to rush to someone's deathbed for the final conversation.

      It's really OK not to be in touch with everyone 24x7. We are not Borg just yet.

      Turn the damn things off and enjoy life.

      --
      Faster! Faster! Faster would be better!
    5. Re:Cinema Wallpaper by Opportunist · · Score: 4, Insightful

      Sometimes I wonder how people survived without being reachable 24/7. Seriously, I am old enough to remember those times.

      At the danger of sounding harsh, but what do you expect to do if your loved one is being rushed to the hospital? Stay and enjoy the movie (without knowing it, or the enjoy part is over). You can't do jack there anyway except standing in the way of the docs trying to save him/her.

      --
      We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
  8. old news by weighn · · Score: 4, Interesting
    I mean, I submitted this in an entirely different month:
    "Tinfoil hat" for your home blocks comms; Wednesday June 27, @01:06PM; Rejected

    If you want to keep up with news like this (recall that "news" comes from Middle English for "new thing") just drop New Scientist and Scientific American into your RSS reader.

    --
    Mongrel News all the news that fits and froths
    1. Re:old news by mcpkaaos · · Score: 2, Insightful

      (recall that "news" comes from Middle English for "new thing")

      I've lived in the 21st century for too long. Now it just means "noise".

      --
      It goes from God, to Jerry, to me.
  9. Tin foil hat == government conspiracy by Anonymous Coward · · Score: 5, Informative

    You should get rid of it anyway. http://people.csail.mit.edu/rahimi/helmet/

  10. Hats? by WiseWeasel · · Score: 4, Funny

    Now if only they could make hats out of this stuff, to protect our brains from their mind control rays...

    --
    "I like systems, their application excepted", George Sand (French)
  11. Say goodbye to using your cellphone indoors!!! by VidEdit · · Score: 2, Interesting

    If signals can't get out, they can't get in either so no using your cell phone inside or taking the cordless landline into the back yard. As for AM and FM radio, well who listens to that at home? (Well, me, since low bitrate music streams suck...)

    Anyways, you need to shield your walls and doors for this window film to be effective. Or you could just use grounded window screens instead... Somehow, I doubt anyone is Van Eck Phreaking your home at the moment

    --
  12. Just what we al needed by SuperKendall · · Score: 4, Insightful

    A way to make cell phone signals even *worse* indoors.

    No Thanks!

    Don't mind a bit if movie theaters heap several layers on the ceiling, walls, and seats though. I'll help put 'em up.

    --
    "There is more worth loving than we have strength to love." - Brian Jay Stanley
  13. I read the subject as... by Aranykai · · Score: 3, Insightful

    "Newly Declassified Windows Film [...]"

    I was like... 'wtf would Microsoft have done that was classified?' I still think it would have been more interesting that way.

    This is non-news. Just some crap that will be bought by the paranoid. Whats next? Roofing underlayment that blocks free radicals?

    --
    If sharing a song makes you a pirate, what do I have to share to be a ninja?
  14. Works great until you... by bremstrong · · Score: 2, Funny

    ...open the front door.

  15. At last... by Anonymous Coward · · Score: 5, Funny

    A version of Windows that can keep things out!

  16. A few months back.. by Enderandrew · · Score: 2, Interesting

    A few months back a friend introduced me to this. He isn't big into technology. He runs a window tinting company and wanted to know how legit this was, so we got some samples and tested it. I'm going to have to send him the link. This could be really big money for him, as he is getting in on the ground floor.

    It appears to work exactly as promised, and honestly, in certain applications it is the only real way to secure wireless data.

    The government declassifies technology all the time, usually after they've developed something better.

    --
    http://blindscribblings.com - Tasty pop-culture in conceptual fashion.
    1. Re:A few months back.. by Enderandrew · · Score: 2, Informative

      Some simple, real basic cheap tests. He had various samples of the film.

      Place it directly over a cell phone, and the signal disappears, for instance. Place it directly between a wireless router, and your wireless card, and you cease to get a signal.

      He insisted he had seen proper rooms done up with the material when he met with the manufacturer, and you could maintain a network inside a building without signal loss, but it would block the signal from getting out.

      We had worked together at a casino where they put 50 access points directly over the new table games section to put in their first ever wireless network. I was arguing that we didn't need 50 access points to cover a very small area, and also arguing the security holes this created, to which the executives said "we'll simply buy another $200,000 firewall to plug the wireless network into. That will make it secure!"

      I kept explaining how I could sit the parking lot (or likely a few blocks away with those 50 access points (salesmen are always objective with how much you need to buy from them) and pick up the signal, and do all kinds of naughty things with it. No one listened, and the casino wasted their money on a very insecure system. My friend (who was then a manager in Slots) remembered all that, and when he discovered this film, he gave me a call and asked me to research it.

      There is little to no information online about it, even though it has been around a long time. However, if I recall the manufacturer (assuming it is the same company in this article, which I can't pull up to the Slashdot effect) insists their product is in the Pentagon, the FBA, CIA, NSA, and all the three-letter agencies.

      --
      http://blindscribblings.com - Tasty pop-culture in conceptual fashion.
  17. Windows Tag? by calciphus · · Score: 2, Insightful

    I know everyone loves to bash Microsoft on /. - but lets be fair, this really shouldn't be tagged with the "Windows" tag.

    Ever wonder why there's a "Linux" and an "Apple" section, but no "Microsoft" or even cleverly abbreviated "M$"?

    There's your tinfoil conspiracy.

    And tinfoil isn't made from tin. Stop calling it that.

    1. Re:Windows Tag? by Anonymous Coward · · Score: 4, Funny

      And tinfoil isn't made from tin. Stop calling it that. Baby powder isn't made from babies either.
    2. Re:Windows Tag? by treeves · · Score: 4, Funny

      But Girl Scout Cookies on the other hand. . .

      --
      ...the future crusty old bastards are already drinking the Kool-Aid.
  18. EMP? You mean electromagnetic pulse? by Cheesey · · Score: 4, Funny

    It can keep signals...out,...even the fabled electronics-destroying electromagnetic pulse generated by a nuclear blast.

    Now that's serious product testing.

    --
    >north
    You're an immobile computer, remember?
  19. Re:Cell Phones by Technician · · Score: 2, Informative

    it also means that you obviously wont be using your cell phone inside the house, you'll still need to go outside

    Not always. Once you have a sealed RF container, you have the choice of what to let in and what to keep out. For example an active Cell/Pager repeater will provide excelent phone and pager coverage in the building. WiFi would not be in the passband and wouldn't get through. If you need it, you can always install an outdoor WiFi antenna and firewall it from your indoor LAN. Now WiFi works, but protected from snoops looking for the secure side of the LAN.

    --
    The truth shall set you free!
  20. Re:if it were effective, it would still be classif by Technician · · Score: 4, Informative

    If it were effective, it would still be classified.

    Not always. Many things that were classified are no longer classified because they became common knowledge and no longer required protection. Some examples are encryption standards, Nuclear basics, some radio modulation techniques, some CPU's, some radio frequencies, and much data from WWII. Even some of the SR71 information is no longer classified.

    The fact a window tinting film can have a metalized film that blocks RF is now common knowledge. Others have stumbled upon the fact. Offices with metalic colors such as bronze, copper or stainless, have had problems with cell and pager coverage. GPS users have had reception problems in some vehicles. Many films are designed to reduce IR transmission to keep the heat out. With all that general knowledge, having a classified film with these properties is a moot point.

    Just because it is declassified does not make it ineffective. The stealth fighter is still a low radar profile item.

    It was classified when the film was used on the cockpit windows of stealth fighters to prevent radar reflections from entering the cockpit and having a retro-reflection back to the radar source. It's now common knowledge the stealth fighters have RF screens over things like Jet intakes and conductive films over windows so the plane's cavities do not reflect a signal back to the direction it came from. This lack of a reflection back to the source is what makes a stealth plane invisable to radar. Very little signal returns. All reflections are sent off to an angle, not back to the source. It's no longer a secret, so the film tech is now declassified.

    If you don't want to spend big bucks for the official military product, visit your local car window tinting shop. Ask for a film that keeps out the heat and has a a nice metalic tint. Ask for samples. Take them outside and lay them on your GPS while watching signal strength. Pick from the ones that kill the GPS reception. Now you have one that blocks far IR, maybe near IR and radio. If you need to block near IR, take a IR modified webcam and see if it is transparant in the near IR. Most non-metalic window tints are water clear in the near IR. An IR camera sees through them like ordinary window glass.

    Sample photos of IR and sunglasses and other materials. Caution, fabric photo may not be safe for work.
    http://images.google.com/imgres?imgurl=http://www. kaya-optics.com/images/kodak_1_s.jpg&imgrefurl=htt p://www.kaya-optics.com/products/applications.shtm l&h=142&w=118&sz=23&hl=en&start=4&tbnid=KD3TcOf3Id c-bM:&tbnh=94&tbnw=78&prev=/images%3Fq%3DIR%2Bphot os%2Bsunglasses%2Btinted%2Bwindow%26gbv%3D2%26svnu m%3D10%26hl%3Den

    --
    The truth shall set you free!
  21. Booom! by minus9 · · Score: 3, Funny

    "It can keep signals in (preventing attempts to spy on electronic communications) or out, minimizing radio interference and even the fabled electronics-destroying electromagnetic pulse generated by a nuclear blast."

    I'm sure being able to view mutant porn after nuclear devastation hits will be a great comfort. Well done to all involved.

  22. people aren't wearing enough by weighn · · Score: 4, Funny

    [Large corporate boardroom filled with suited executives]
    Exec #1: Item six on the agenda: "The Meaning of Life" Now uh, Harry, you've had some thoughts on this.
    Exec #2: Yeah, I've had a team working on this over the past few weeks, and what we've come up with can be reduced to two fundamental concepts. One: People aren't wearing enough hats. Two: Matter is energy. In the universe there are many energy fields which we cannot normally perceive. Some energies have a spiritual source which act upon a person's soul. However, this "soul" does not exist ab initio as orthodox Christianity teaches; it has to be brought into existence by a process of guided self-observation. However, this is rarely achieved owing to man's unique ability to be distracted from spiritual matters by everyday trivia.
    Exec #3: What was that about hats again?
    Exec #2: Oh, Uh... people aren't wearing enough.
    Exec #1: Is this true?
    Exec #4: Certainly. Hat sales have increased but not pari passu, as our research...
    Exec #3: [Interrupting] "Not wearing enough"? enough for what purpose?
    Exec #5: Can I just ask, with reference to your second point, when you say souls don't develop because people become distracted...
    [looking out window]
    Exec #5: Has anyone noticed that building there before?

    --
    Mongrel News all the news that fits and froths
  23. Finally! by DoofusOfDeath · · Score: 4, Funny

    I'd give a lot to see that smug "Can you hear me now?" guy walk into one of those buildings.

  24. Radio waves, good. by Kagura · · Score: 2, Funny

    But I want to know when they will invent a window covering that blocks out visible light. I wonder if they have a classified solution. :)

  25. Not a bad thing by ajs318 · · Score: 2, Insightful

    I've been saying for a long time that what the world needs is a simple passive defence against mobile phones. Putting up signs only pisses off people who weren't going to be using a mobile anyway, and there are enough people who ignore them to make them ineffective.

    A faraday shield is unintrusive (if implemented properly) and can't be ignored. Nobody thinks their rights are being violated when they can't get a signal ..... but they also can't annoy people with a phone if it simply doesn't work.

    --
    Je fume. Tu fumes. Nous fûmes!