Recently, Liu et al. proposed a quantum private comparison (QPC) based on Bell entangled states (Liu et al. in Commun. Theor. Phys. 57(4): 583, 2012). This paper points out a security loophole in Liu et al.'s protocol, in which the third party can disclose the private information of both users. In addition, an improvement is proposed to avoid the loophole.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)