[tgbugs]

As a giant identifier nerd, this is incredibly cool. Any insights/thoughts on tamper resistance/non-duplication? I realize that this is a bit outside the original use case/threat model, but would it be possible to ensure that any physical injury to the coating would ensure that the code would no longer match? Seems like a challenge because you want robust matching but not robust enough to allow someone to substitute or reproduce the exact pattern.

I'm fairly certain that this cannot defend against a determined adversary buying up a bunch of pills, reading out the ids, and then reproducing the patterns (which would already be in the database) or similar enough patterns via a non-random process. Only useful for substitution attacks where someone trusts a pill because it is in a database without realizing that its contents could have been substituted for e.g. poison.

This may be obvious, but it also seems critical for any database that might use these to have expiration dates, otherwise expired pills could be bought in bulk and resold or have their codes reused.

[michaelcampbell]

> As a giant identifier nerd,

Not something you hear often. =D