-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA512 hello Sampo! ‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐ On Sunday, August 1st, 2021 at 3:54 PM, Sampo Syreeni <decoy@iki.fi> wrote:
Many years ago I posted an idea of mine about cryptographic physical watermarking of things, such as paper money, or maybe missiles. Whatnot. The idea was that you'd do some chaotic physical process in order to lay down a physical watermark, then image it, and finally digitally sign what was seen via asymmmetric cryptography.
...
My first and best idea about how to make this physical nonce is to mix a couple of dozen well cut differently fluorescent plastic fibers into the paper or plastic fiber pulp from which the bill/artifact is made.
check out physically unclonable functions: [ https://en.wikipedia.org/wiki/Physical_unclonable_function ] in particular optical PUFs. check out the integrated PUF from consumer hardware in this paper :) - https://eprint.iacr.org/2013/215.pdf best regards, -----BEGIN PGP SIGNATURE----- iNUEAREKAH0WIQRBwSuMMH1+IZiqV4FlqEfnwrk4DAUCYQhaGl8UgAAAAAAuAChp c3N1ZXItZnByQG5vdGF0aW9ucy5vcGVucGdwLmZpZnRoaG9yc2VtYW4ubmV0NDFD MTJCOEMzMDdEN0UyMTk4QUE1NzgxNjVBODQ3RTdDMkI5MzgwQwAKCRBlqEfnwrk4 DD58AP402kQPTbjDJzMzm3uc4Dj6OXRIOzTTy7QtOuOLSSY3VwEAiZN78MRdUgdP vsRruJOiGaJH9S0IUfM6HnwB+eQv5Yg= =JnyH -----END PGP SIGNATURE-----