[Cryptography] Crypto and rustling

Joseph Kilcullen kilcullenj at gmail.com
Sat Nov 19 11:21:00 EST 2016

If they are Friesian cattle then you can hire an artist to sketch 
drawings of the patchwork black and white pattern of each cow. Kinda 
like taking note of the brand that Mother Nature put on them. Its 
cryptography in the sense that each cow’s pattern is a ‘Physical 
unclonable function’. Once you take note of the pattern you simply 
authenticate any given cow against a register of owners. Though that 
sounds like a computer database which is not available in the 19th 
century. I guess the local sheriff could use a copybook of drawings of 

To me, your question is about counterfeiting & authentication. The 
solution presented is based on anti-counterfeiting solutions referenced 
in some of my earlier posts.

More information about the cryptography mailing list