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arXiv · 0903.4744

Deterministic quantum-public-key encryption: forward search attack and randomization

Georgios M. Nikolopoulos·Lawrence M. Ioannou
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Abstract

In the classical setting, public-key encryption requires randomness in order to be secure against a forward search attack, whereby an adversary compares the encryption of a guess of the secret message with that of the actual secret message. We show that this is also true in the information-theoretic setting -- where the public keys are quantum systems -- by defining and giving an example of a forward search attack for any deterministic quantum-public-key bit-encryption scheme. However, unlike in the classical setting, we show that any such deterministic scheme can be used as a black box to build a randomized bit-encryption scheme that is no longer susceptible to this attack.

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Georgios M. Nikolopoulos, Lawrence M. Ioannou. 2009-03-27. Deterministic quantum-public-key encryption: forward search attack and randomization. https://doi.org/10.1103/physreva.79.042327

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