PUFs: Myth, Fact or Busted? A Security Evaluation of Physically Unclonable Functions (PUFs) Cast in Silicon

  • Stefan Katzenbeisser
  • Ünal Kocabaş
  • Vladimir Rožić
  • Ahmad-Reza Sadeghi
  • Ingrid Verbauwhede
  • Christian Wachsmann
Part of the Lecture Notes in Computer Science book series (LNCS, volume 7428)


Physically Unclonable Functions (PUFs) are an emerging technology and have been proposed as central building blocks in a variety of cryptographic protocols and security architectures. However, the security features of PUFs are still under investigation: Evaluation results in the literature are difficult to compare due to varying test conditions, different analysis methods and the fact that representative data sets are publicly unavailable.

In this paper, we present the first large-scale security analysis of ASIC implementations of the five most popular intrinsic electronic PUF types, including arbiter, ring oscillator, SRAM, flip-flop and latch PUFs. Our analysis is based on PUF data obtained at different operating conditions from 96 ASICs housing multiple PUF instances, which have been manufactured in TSMC 65 nm CMOS technology. In this context, we present an evaluation methodology and quantify the robustness and unpredictability properties of PUFs. Since all PUFs have been implemented in the same ASIC and analyzed with the same evaluation methodology, our results allow for the first time a fair comparison of their properties.


Physically Unclonable Functions (PUFs) ASIC implementation evaluation framework unpredictability robustness 


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Copyright information

© International Association for Cryptologic Research 2012

Authors and Affiliations

  • Stefan Katzenbeisser
    • 1
  • Ünal Kocabaş
    • 1
  • Vladimir Rožić
    • 3
  • Ahmad-Reza Sadeghi
    • 2
  • Ingrid Verbauwhede
    • 3
  • Christian Wachsmann
    • 1
  1. 1.Technische Universität Darmstadt (CASED)Germany
  2. 2.Technische Universität Darmstadt and Fraunhofer SIT DarmstadtGermany
  3. 3.KU Leuven, ESAT/COSICLeuvenBelgium

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