Multiparty quantum privacy comparison method based on d-level cat state and d-level Bell state entanglement swapping

Abstract

The invention provides a multiparty quantum privacy comparison method based on d-level cat state and d-level Bell state entanglement swapping. A half-loyal third party is allowed to do on own will but cannot conspire with any party; in the invention, n parties encode their own secrets by use of a unitary operation, and the equality of the secrets of the n parties can be compared by only executing once. The external attack and the participant attack are resisted in the premise of not adopting a quantum key to produce a key to guarantee the security. One party cannot obtain the secrets of other parties except the circumstance that their secrets are completely same. The half-loyal third party cannot obtain any information about the secret of these parties except the comparison result.

Description

technical field

[0001] The invention relates to the field of quantum cryptography. The invention designs a multi-party quantum privacy comparison method based on the entanglement exchange of the d-level cat state and the d-level Bell state to solve the equality comparison problem of multiple user secrets. Background technique

[0002] Since Bennett and Brassard [1] first proposed the concept of quantum cryptography in 1984, many secure quantum cryptography methods have been designed, such as quantum key distribution (Quantum Key Distribution, QKD) [2-5], quantum secure direct communication ( Quantum Secure Direct Communication, QSDC)[6-8], quantum teleportation[9-11], etc.

[0003] Secure multi-party computation (Secure multi-party computation, SMC) is a basic primitive problem of modern cryptography, dedicated to computing a function with secret inputs from different parties in a distributed network without revealing the true value of each secret input. content. It has a...

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