4 ms·

I read the paper, and I really have a hard time understanding what kind of threat model the authors are proposing. If the details of the watermark are public,

I read the paper, and I really have a hard time understanding what kind of threat model the authors are proposing. If the details of the watermark are public, as they suggest, what would stop a counterfeit manufacturer from just writing their own watermark to their own devices? Wouldn't that be just as easy as printing a fake logo on the IC package? I suppose you could prevent this with some kind of scheme using digital signatures, but the paper never suggests or considers that. And if you had a way to generate a "certificate of authenticity" for each device, what would be the point of storing it as a wear pattern, instead of in an EEPROM or something? The authors only say that their proposal "does not require any hardware modification", which seems like a pretty flimsy justification.

justsomehnguy 5y ago
> scheme using digital signatures The simpliest one would be to have "CHIP S/N: XXXX MFG DATE: YY/MM/DD" signed by some CA and watermarked on each chip. That doesn't prevent for a counterfeit manufacturer from grabbing a handful of original chips and watermarking a series of their counterfeit chips with it. So it boils down to: a) no watermark on a chip what should be watermarked: obvious counterfeit b) one watermark on all chips: obvious counterfeit c) a valid watermarks on a shipment of chips: if you order a ton of them AND you bothered to setup both the tests and means to store and compare the results, so it would be obvious when you receive the shipment of chips with watermarks what you already has tested. for anyone else it would be c2) chips with a valid watermarks: not a counterfeit