Arsen Ray A. wrote:
Now the question I have is what if the forgery is done so well, would it fool the scanner and pass the signature? ie: What if you take a picture of the painting or part or whatever using high resolution film, etc. Would it pass the signature?
I don't know (but I'll make some speculative/engineering guesses), as I never saw the system...like I said, I heard a verbal description of it some years back (from Jim Omura, of Cylink, now famous for suing RSADSI). First, photo-reproduced art is almost never confused with the real thing. Surface texture, brush strokes, light at different angles, etc. Second, I could imagine the scanner system using light at two or more angles specifically to provide better protection against forgeries. (In the intended main applicaiton, that of detecting machine part forgeries, the pattern of natural scratches and abrasions, and grains/regions in the metal, would be essentially impossible to mechanically reproduce. Not completely impossible, but very difficult, and hence not cost-effective.) Anyone interested in pursuing this may be find out if Light Signatures still exists. Omura may know, and someone at RSADSI probably would have records of their licensing arrangements. --Tim May -- .......................................................................... Timothy C. May | Crypto Anarchy: encryption, digital money, tcmay@netcom.com | anonymous networks, digital pseudonyms, zero 408-688-5409 | knowledge, reputations, information markets, W.A.S.T.E.: Aptos, CA | black markets, collapse of governments. Higher Power: 2^859433 | Public Key: PGP and MailSafe available. "National borders are just speed bumps on the information superhighway."