A Protocol for the Quantum Private Comparison of Equality with χ-Type State

Abstract

We present a new quantum protocol for comparing the equal information with the help of a semi-honest third party (TP). Different from previous protocols, we utilize the four-particle χ -type states as the information carriers. Various kinds of outside attacks and participant attacks are discussed in detail. One party cannot learn the other's private information. The TP cannot learn any information about the private information, even about the comparison result or the length of secret inputs.

Quantum Private Comparison Using Genuine Four-Particle Entangled States

“…Recently Liu et al proposed a private comparison protocol with χ -type state [39] by using quantum-one-time pad. And in this paper, we give another method for the private comparison based on χ state, which uses the quantum superdense coding.…”

Efficient Solutions to Two-Party and Multiparty Millionaires’ Problem

“…Motivated by Goldwasser's predictions, cryptographic researchers have studied many SMC problems, including private sorting problems [4], private determination of the relationships among sets [5] and geometry [6], private voting problems [7], and private data mining [8]. Goldreich [9] studied theoretical SMC problems and established a simulation paradigm that has been extensively used to evaluate the security of SMC protocols.…”

New Quantum Private Comparison Protocol Using χ-Type State

“…And this protocol provided easier implementation as well as better qubit efficiency than the other QPCs. In [29,30], Liu et al proposed two new QPC protocols based on the triplet W states and χ −type genuine four-particle entangled states. These two protocols also included a semi-honest TP.…”

“…Enlightened by the works of [26][27][28][29][30], we proposed a new protocol for dealing with the private comparison of equal information based on χ -type state…”

“…Comparing to the works of [30], we only need to prepare one type of χ -type state and only need N χ-type states in our new protocol. We also need to perform the Pauli operation on particles to encode information and don't need to use the entangled character of four-particle χ -type state.…”