There is ongoing and quite promising research with prototypes presented about using physically unclonable functions (PUFs) in authentication. If they are practically unclonable, how is a PUF-based device authenticated?
If they are practically unclonable, how is a PUF-based device authenticated?
Consider the example of a smart-card chip, assuming that it has a puf-based circuit. If reliable enough then this chip will produce a unique key for a given challenge.
Even if an adversary attempts to replicate the same circuit with the same response the output key will be different provided. As process variation is naturally occurring variation,when integrated circuits are fabricated. Due to process variation, each transistor parameters follows a gaussian distribution with a specific variance. With better fabrication process, this variance can be reduced but can't be neglected completely. So as long as process variation is there different puf-circuit will produce the unique key, provided they meet certain puf-standards.