Balanced arbiter physical uncloneable functions
Vyacheslav N. Yarmolik, Alexander A. Ivaniuk · Bezopasnost informacionnyh tehnology · 2023
The problem of constructing a new class of physically unclonable functions of the arbiter type (APUF) based on the construction of balanced pairs of paths is solved. This makes it possible to significantly increase the stability, uniqueness and uniformity of the APUF. The relevance of the proposed research is associated with the active development of physical cryptography used for the identification of electronic devices and for the generation of cryptographic keys. It is shown that the classical APUF uses a standard basic element that performs three functions, namely, the function of generating a signal delay Generate, the function of choosing a pair of paths Select and the function of switching paths Switch. The execution of all functions by the basic element simultaneously leads to the asymmetry of pairs of paths, which causes a deterioration in the characteristics of the APUF and entails balancing of the paths. As an alternative to the standard basic element, two of its modifications are proposed, in which the Generate function is performed on additional delay lines, and the Switch function on the multiplexer. The use of delay lines with signal delay times much longer than on multiplexers allows constructing the balanced APUF. The proposed approach for building balanced APUF, based on the use of modified basic elements, has demonstrated its efficiency and prospects, including the case of implementing APUF on programmable structures. Practical studies were carried out by a comparative analysis of the classical APUF and balanced APUF implemented on modern FPGAs. The effect of improvement of the characteristics of similar PUFs has been experimentally confirmed, and, first of all, a noticeable improvement in the stability, uniqueness and uniformity of APUFs.