Abstract

The use of physically unclonable functions (PUFs) as a new cryptographic technique is gaining attention. Challenge-response authentication and key generation (key storage) are well known as major applications using PUFs. When PUFs are applied to these applications, min-entropy estimation is essential. The min-entropy is a measure of the lower bound of the unpredictability of PUF responses. Many studies have estimated the min-entropy of PUFs, and several of these studies dealt with PUFs with independent and identically distributed (IID) PUF responses. Few studies have focused on non-IID PUFs. One reason is that some causes of entropy loss are complicatedly intertwined, and the entropy estimation of non-IID PUFs is hard. Thus, it is first necessary to break down the intertwined causes to estimate min-entropy. In this paper, we present typical causes of entropy loss during PUF implementation and propose a cause analysis method using the Inter-Hamming distance (HD), which is one of major performance metrics of PUFs. And the proposed method was applied to prototyped PUFs designed with a 180-nm CMOS process. We demonstrate that the causes of entropy loss on each PUF can be broken down according to the analysis results.

Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call