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arXiv · 1308.2777

Cryptanalysis of a multi-party quantum key agreement protocol with single particles

Wei Huang·Qiao-Yan Wen·Bin Liu·Qi Su·Fei Gao
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Abstract

Recently, Sun et al. [Quant Inf Proc DOI: 10.1007/s11128-013-0569-x] presented an efficient multi-party quantum key agreement (QKA) protocol by employing single particles and unitary operations. The aim of this protocol is to fairly and securely negotiate a secret session key among $N$ parties with a high qubit efficiency. In addition, the authors claimed that no participant can learn anything more than his/her prescribed output in this protocol, i.e., the sub-secret keys of the participants can be kept secret during the protocol. However, here we points out that the sub-secret of a participant in Sun et al.'s protocol can be eavesdropped by the two participants next to him/her. In addition, a certain number of dishonest participants can fully determine the final shared key in this protocol. Finally, we discuss the factors that should be considered when designing a really fair and secure QKA protocol.

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Wei Huang, Qiao-Yan Wen, Bin Liu, Qi Su, Fei Gao. 2013-08-13. Cryptanalysis of a multi-party quantum key agreement protocol with single particles. https://doi.org/10.1007/s11128-014-0758-2

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