What prevents somebody from scanning it and reconstructing the position of the metal pieces?
Perhaps a better solution is to create a small chip powered by electric induction. The chip would have an embedded private key and solve challenge-response queries issued by the scanning device.
I'm not sure how that compares in cost though.
Edit: it looks like these already exist and cost less than 10 cents a piece. They are called NFC tags.
Perhaps a better solution is to create a small chip powered by electric induction. The chip would have an embedded private key and solve challenge-response queries issued by the scanning device.
I'm not sure how that compares in cost though.
Edit: it looks like these already exist and cost less than 10 cents a piece. They are called NFC tags.