Paper 2018/171

On the Complexity of Simulating Auxiliary Input

Yi-Hsiu Chen, Kai-Min Chung, and Jyun-Jie Liao


We construct a simulator for the simulating auxiliary input problem with complexity better than all previous results and prove the optimality up to logarithmic factors by establishing a black-box lower bound. Specifically, let $\ell$ be the length of the auxiliary input and $\epsilon$ be the indistinguishability parameter. Our simulator is $\tilde{O}(2^{\ell}\epsilon^{-2})$ more complicated than the distinguisher family. For the lower bound, we show the relative complexity to the distinguisher of a simulator is at least $\Omega(2^{\ell}\epsilon^{-2})$ assuming the simulator is restricted to use the distinguishers in a black-box way and satisfy a mild restriction.

Available format(s)
Publication info
Published by the IACR in EUROCRYPT 2018
Leakage Simulation LemmaSimulating Auxiliary InputLeakage-Resilient Stream-CipherLeakage Chain RuleDense Model TheoremImpagliazzo's Hardcore LemmaComputational Min-Entropy
Contact author(s)
jjliao @ iis sinica edu tw
2018-02-14: received
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Creative Commons Attribution


      author = {Yi-Hsiu Chen and Kai-Min Chung and Jyun-Jie Liao},
      title = {On the Complexity of Simulating Auxiliary Input},
      howpublished = {Cryptology ePrint Archive, Paper 2018/171},
      year = {2018},
      note = {\url{}},
      url = {}
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