| http://www.sciam.com/article.cfm?articleid=6670BF9B-E7F2-99DF-3EAC1C6DC382972F | | A company is selling a window film that blocks most RF signals. The | obvious application is TEMPEST-shielding. I'm skeptical that it will | be very popular -- most sites won't want to give up Blackberry and | cell phones... Real life follows fiction? There was a Law and Order episode a year or two back in which a high-tech company used some alleged technology like this - a fine mesh of wires over the windows. (An important clue was one of the detectives noticing that the mesh had been disturbed. Someone had replaced the wires in a small region with black thread, then hid a cell-phone repeater outside the window. As I recall, the reason for doing was just your typical hacker "you try to stop me, I'll get around you" trick.)
There were also reports not that long ago of a paint that provided RF shielding. On a more refined basis, there was some kind of material suitable for walls that had embedded antennas. You cut them for a particular frequency range, and they provided very good shielding in that range. There is clearly a demand for this kind of thing. New technologies are making a hash of the old (sometimes not so old!) rules. Two examples: - The day of open access to the Internet from businesses is long is long gone in most places. All kinds of concerns feed into this; a big part is concern about liability when employees access "inappropriate" sites. This will all seem a bit silly when the penetration of high-speed wireless Internet access reaches reasonable levels. - Insider trading rules have placed all kinds of interesting restrictions on how trading firms do business. In particular, every phone message in and out of "sensitive" areas is recorded, as is all email. But cell phones, text messaging, and so on bypass all that. I gather some firms are responding by requiring that employees use only company-provided cell phones. (Whether those calls get recorded is another question.) How well they'll be able to maintain such policies, as cell phones morph into multi-function personal devices, is an open question. With all this going on, the desire to just finesse the whole problem by physically blocking signals is certainly only going to grow. Interesting times. -- Jerry --------------------------------------------------------------------- The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to [EMAIL PROTECTED]