Paper 2019/1091

Short Paper: XOR Arbiter PUFs have Systematic Response Bias

Nils Wisiol and Niklas Pirnay


We demonstrate that XOR Arbiter PUFs with an even number of arbiter chains have inherently biased responses, even if all arbiter chains are perfectly unbiased. This rebukes the believe that XOR Arbiter PUFs are, like Arbiter PUFs, unbiased when ideally implemented and proves that independently manufactured Arbiter PUFs are not statistically independent. As an immediate result of this work, we suggest to use XOR Arbiter PUFs with odd numbers of arbiter chains whenever possible. Furthermore, our analysis technique can be applied to future types of PUF designs and can hence be used to identify design weaknesses, in particular when using Arbiter PUFs as building blocks and when developing designs with challenge pre-processing. Finally, we discuss consequences for the parameter recommendations of the Interpose PUF. Investigating the reason of the systematic bias of XOR Arbiter PUF, we exhibit that Arbiter PUFs suffer from a systematic uniqueness weakness.

Available format(s)
Publication info
Preprint. MINOR revision.
Physically Unclonable FunctionBiasArbiter PUFInterpose PUF
Contact author(s)
nils wisiol @ fu-berlin de
2019-09-29: received
Short URL
Creative Commons Attribution


      author = {Nils Wisiol and Niklas Pirnay},
      title = {Short Paper: XOR Arbiter PUFs have Systematic Response Bias},
      howpublished = {Cryptology ePrint Archive, Paper 2019/1091},
      year = {2019},
      note = {\url{}},
      url = {}
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