Research On Delay-based Physical Unclonable Function

With the rapid development of information technology,cyberspace security issues have attracted more and more attention.Physical Unclonable Function(PUF)as a new type of hardware security protection method has received extensive attention from researchers.PUF utilizes the random differences in the chip manufacturing process due to the differences in manufacturing processes to achieve a set of key information similar to a physical fingerprint or a set of unpredictable responses generated by external excitation.Physical unclonable functions have the characteristics of stability,uniqueness,and unclonability,which enable them to generate unique digital signatures,so they are widely used in the field of hardware security(such as IP/IC protection,key generation,etc.).This paper starts with the classification,application,attributes and evaluation of PUF,and systematically and comprehensively introduces and elaborates the characteristics of PUF.Next,the paper will give a detailed explanation of a classic PUF type-the delay-based PUF type.This paper first introduces the existing PUF types based on delay,including arbiter PUF,ring oscillator-based PUF(RO PUF)and glitch PUF,etc.Next,compare the similarities and differences among the three existing delay PUF types,and finally summarize the shortcomings of the current classic delay PUF types.Secondly,in view of the shortcomings and deficiencies of the above-mentioned classic delay PUF types,this paper proposes a new type of delay PUF scheme—Combinational Circuit Delay-PUF(CCD-PUF)to reduce the existing PUF’s consumption of hardware resources and improve the uniqueness and stability of the delay PUF type.This paper conducts statistics and evaluation based on the precise time delay generated by CCD-PUF,and the results show that the PUF circuit combined with precise time delay can effectively improve the uniqueness of the existing time delay PUF.In addition,in the case of generating excitation response pairs with the same number of bits,the CCD-PUF effectively reduces FPGA hardware resource consumption compared with the existing delay PUF.This result shows that the combinational circuit structure in this paper is of great significance to the hardware consumption and performance improvement of the delay type PUF.Based on the idea of combinational circuit,this article discusses the basic structure,working principle,overall design,performance index and other aspects of CCD-PUF in turn.In addition,the paper considers the application of the CCD-PUF structure in the direction of hardware Trojans,and uses the working principle of CCD-PUF to generate accurate time delays to detect the existence of hardware Trojans.