Necessity of parameter randomization in quantum contract signing. (English) Zbl 1474.81018

Louka, Hana Almoner

Mat. Vesn. 69, No. 1, 65-74 (2017).

Summary: We present a proof that randomization is necessary in quantum contract signing protocol of N. Paunković, J. Bouda and P. Mateus [Phys. Rev. A (3) 84, No. 6, Article ID 062331, 11 p. (2011; doi:10.1103/PhysRevA.84.062331)]. We prove that for any fixed value of the protocol parameter \(\alpha \), for large \(N\) the probability of cheating can be as high as 25%, where \(N\) is the number of messages exchanged between the parties, and thus without randomization the protocol is not fair.

MSC:

81P94	Quantum cryptography (quantum-theoretic aspects)
94A60	Cryptography

Keywords:

contract signing protocol; parameter randomization; qubit

References:

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[12]	Faculty of Mathematics, University of Belgrade, Studentski trg 16, Beograd, Serbia
[13]	E-mail:[e-mail]