Secure multi-party quantum summation is an important branch of secure multi-party quantum computation. Recently, Ji et al. suggested a secure multi-party quantum summation scheme based on the entanglement swapping between the d-level Bell state and the d -level n+1-particle cat state (Quantum Inf Process (2019)18:168). In this paper, it is pointed out that Ji et al.’s secure multi-party quantum summation scheme has a security loophole, i.e., the third party (TP) can obtain the secret numbers of n communicants without being discovered. Then, in order to avoid this security loophole, an improvement is suggested by adopting the method of encrypting the secret integers of n communicants with a pre-shared private key sequence among them.

中文翻译：

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用于安全多方求和的量子协议的改进

安全多方量子求和是安全多方量子计算的一个重要分支。最近，Ji 等人。提出了一种基于 d 级贝尔态和 d 级 n+1 粒子猫态之间的纠缠交换的安全多方量子求和方案（Quantum Inf Process (2019)18:168）。本文指出姬等人的安全多方量子求和方案存在安全漏洞，即第三方（TP）可以在不被发现的情况下获取n个通信者的秘密号码。那么，为了避免这个安全漏洞，提出了一种改进方法，采用对n个通信者的秘密整数进行加密的方法，在它们之间预先共享一个私钥序列。