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Richard Stallman Accosted For Tinfoil Hat
ndansmith writes "Bruce Perens posts in his blog about an amusing encounter between Richard Stallman and United Nations security at the World Summit on the Information Society in Tunis. It seems that RFID technology, which Stallman opposes for privacy reasons, was used in the identification badges for the conference. From the blog: 'You can't give Richard a visible RF ID strip without expecting him to protest. Richard acquired an entire roll of aluminum foil and wore his foil-shielded pass prominently.' During a keynote speech, Stallman also passed around the tinfoil for other to use as well. It seems that UN security was not amused, however, as they would not let him leave the room for some time." What makes this even funnier, of course, is that tin foil hats won't stop them.
If the holeys in a mesh are half the size of the average wavelength of the radiation, practically none will get through, assuming it is made of the right material. The proper size mesh for RFID technology is left as an excerise for the reader.
Even those who arrange and design shrubberies are under considerable economic stress at this period in history.
Exactly. The story does NOT say "Richard Stallman Accosted For Tinfoil Hat". It says he wrapped his RFID card in aluminum foil, which is 100% effective in preventing reading the card without the card carrier's knowledge. The story also says that Mr. Stallman willingly took off the foil at checkpoints.
Actually, beeing an electrical engineer, I can tell you that aluminum or tin would be an equally effective shield for RFID or any other frequency in which it is relativly large enough. (Relative to the wavelength used by the transmitting device..in the case of RFID it can use anything from 52 mm to 2398 m. No matter the frequency, encasing an entire object in metal foil will block its RF output as explained loosely below.)
If you wrap any RF transmitting device in tin OR aluminum foil, you are going to completely shield the device and no RF will get in or out because the foil would act as a farady cage.
This is because aluminum conducts electricity just fine, and as RF is composed of electro-magnetet waves, a solid conducting surface will act as a ground (short) and bounce the signal. If there is no way for the signal to escape, it wont.
Any electrically conductive material would have this property. You could (and it has been done many times) make a faraday cage out of aluminum just as easily as steel or tin. Aluminum of course only has about 60 percent of the electrical conductivity of copper so copper (actually silver but obviously too expensive) would be the ideal material, but for weak signals like RFID it is irrelivant and both would work fine.
It's easier to fight for one's principles than to live up to them.
lead is the only way to go
I used to use a anti-xray film bag for shoplifting, works a treat
There are places where the networks are not touching,and there are places where they are-Boeing's Lori Gunter
Ladies and gents: Aluminum foil may not work for head-gear, but it will work just dandy for covering an RFID tag.
;~)
Tag == 100% wrapped.
Head != 100% wrapped (one would hope)
Aluminum foil is conductive. That and complete coverage is all you need for a faraday cage.
There are like 30 posts already that act like it won't work: it will. Want to test it? Wrap your walkman in foil and try to listen to FM. Freqs are different for RFID (probably), but it doesn't matter.
Take care not to touch the ant. of the radio to the foil though, or you may actually improve reception
You might want to RTFA again and pay attention this time.
He joked about killing another participant *After* being detained and released and allowed to attend another panel. Not only that, but he joked about it personally to Bruce Perens only after Bruce assured Richard of their diplomat status.
so, RTFAMC
From TFA: (Emphasis mine)
Want a high quality FOSS RTS game? Try Warzone 2100!
Like that would make headlines? RMS is going for max publicity.
AT&ROFLMAO
The UN has a huge positive effect on the world. Examples:
It strikes me that, of the people who are wholly negative of the UN, the vasty majority are from the USA. It's not surprising, given that the UN are criticising the USA for blocking their torture investigations at the moment.
I don't think you'll find anybody claiming that the UN is a perfect organisation. But only trolls and ignorant people could claim that the UN is not worth supporting.
Bogtha Bogtha Bogtha
I'm sorry, I thought it was obvious that the MIT article was a joke. Now people are quoting it as fact.
As smart as those MIT students may be they failed to explain why it amplified the signal.
Simply put, the 'tin foil' or aluminum hat they constructed was a parabolic antenna with the test subjects brain as its focal point. Go back and look at those pictures in the MIT article and see for yourself.
You can in fact shield an object if you *completly* enclose said object with aluminum foil (it's conductive). However, copper foil and screen is the standard for shielding used by professionals.
The enclosure doesn't have to be air tight. But the gaps or holes in the foil need to be smaller then the wavelength your trying to attenuate. This is why RF "screen rooms" can use copper screen instead of solid copper and still be effective to up around 3 GHz.
The more you know...
The U.N. general from Canada motioned to intervene. The U.S. refused. From your link:
The U.N. itself cannot do anything: It's a place for the member nations to talk. If the biggest member decides that a genocide is not worth the risk of potential military casualties, then the fault for inaction is not with the U.N. for trying, but for the member nation for refusing to act.
You can't take the sky from me...
Money owed by U.S. to U.N.: $1bn
9 p3.htm
Money owed by U.N. to U.S.: $4.7bn
http://usgovinfo.about.com/library/weekly/aa10319
Slay a dragon... over lunch!
My point is that it is not aversion to change that causes his site to be a little behind technologically. It is time constraints of everyone involved.