Asynchronous Physical Unclonable Functions – AsyncPUF

  • Julian Murphy
Conference paper
Part of the Communications in Computer and Information Science book series (CCIS, volume 287)


Physically Unclonable Functions (PUFs) exploit the physical characteristics of silicon and provide an alternative to storing digital encryption keys in non-volatile memory. A PUF maps a unique set of digital inputs to a corresponding set of digital outputs. In this paper, the use of asynchronous logic and design techniques to implement PUFs is advocated for Asynchronous Physically Unclonable Functions (APUFs). A new method of using asynchronous rings to implement PUFs is described called AsyncPUF which features inherent field programmability. It is both a novel and holistic PUF design compared to the existing state-of-the-art as it naturally addresses the two challenges facing PUFs to-date that prevent wide-spread adoption: robustness and entropy. Results of electrical simulation in a 90 nano-metre lithography process are presented and discussed.


Cryptography Physically Unclonable Functions PUFs Asynchronous Physically Unclonable Functions Clockless Physically Unclonable Functions 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • Julian Murphy
    • 1
  1. 1.Centre for Secure Information TechnologiesQueens University BelfastBelfastUnited Kingdom

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