Helper-less physically unclonable functions and chip authentication

Physically Unclonable Functions (PUFs) have been recently proposed as a way to include, in chips, functions that can act as “fingerprints” of the chip, to be used in applications like chip authentication (strong PUF) or private ID generation (weak PUF). Most of the schemes proposed for weak PUF exploit helper data to make the PUF more reliable. The use of an helper, however, has some drawbacks such as complexity and the introduction of a possible attack point. In this manuscript we propose the use of a new type of weak PUF called helper-less PUFs (H-PUF) that does not require the use of helper data. We analyze theoretically the problem of designing an H-PUF and use the result to show how an H-PUF can be built. We also show that the proposed PUF, albeit being of weak type, can also be used for chip authentication.