Quantum Private Comparison Protocol Research Articles

Security analysis of multi-party quantum private comparison protocol by model checking

This paper presents an analysis method for quantum information protocols based on model checking, with special focus on the quantum privacy comparison (QPC). The security properties of these protocols can be proved but in ways with much difficulty. Here we will discuss a probabilistic model checking tool — PRISM to verify specific properties of QPC protocol with multi-body and PRISM to verify specific properties of quantum private comparison (QPC) protocol with multi-party and d-dimensional entangled states.

Quantum private comparison protocol with cloud quantum computing

SummaryBecause privacy problems with big data impede progress at all phases of the pipeline that can create value from data, Alice and Bob have to perform private queries in order to obtain the private comparison results of big data. Suppose that the cloud devices are with the capacity of conventional and quantum computation, an efficient quantum private comparison protocol with ring‐trip transmission by safe cloud quantum computing in the quantum Internet is proposed. Two participant parties Alice and Bob, with the help of a semi‐trusted third party and cloud device by simple quantum measurements and mathematical operation, can compare the equality of their secret information without revealing the content of secret information. We show that our protocol can resist the eavesdropper Eve's intercept–resend attack, entangle–measure attack, and Trojan horse attack to cloud device, participant's intercept–measure–resend attack, and third party's attack. The qubit efficiency of our protocol approaches to 100%. We also analyze the connection between Eve's obtained information and the fidelity of secret information in detail. Copyright © 2015 John Wiley & Sons, Ltd.

Quantum private comparison with a malicious third party

In this paper, we will show that quantum private comparison protocol is secure when a malicious third party is presented. The security of the protocol is considered in a cheat-sensitive model, in which the TP is kept honest by the possibility of being caught cheating. Besides, we enhance the privacy of the quantum private comparison protocol, where the participants' inputs and the comparison result can be preserved. Furthermore, in contrast to pervious protocols requiring a large amount of quantum resources, such as entanglement and quantum memory, our protocol is based on BB84 protocol, which is more feasible for practical applications. Finally, we analyze the security of the presented protocol.

Quantum Multi-party Private Comparison Protocol using d-dimensional Bell States

In this paper, we present a quantum private comparison(QPC) protocol for n parties. N parties can compare whether their information are equal or not in one execution of our protocol. With the help of a semi-honest third party (TP), the quantum multi-party private comparison protocol uses the d-dimensional Bell states as the information carriers and uses a special property of the d-dimensional Bell states to perform the equality comparison. Various kinds of outside attacks and participant attacks are discussed in detail. One party cannot learn any information about the others’ private information except the comparison result. The TP cannot learn any information about the private information except the comparison result.

Multi-party quantum private comparison protocol based on $$d$$ d -dimensional entangled states

In this paper, a novel quantum private comparison protocol with $$l$$l-party and $$d$$d-dimensional entangled states is proposed. In the protocol, $$l$$l participants can sort their secret inputs in size, with the help of a semi-honest third party. However, if every participant wants to know the relation of size among the $$l$$l secret inputs, these two-participant protocols have to be executed repeatedly $$\frac{l(l-1)}{2}$$l(l-1)2 times. Consequently, the proposed protocol needs to be executed one time. Without performing unitary operation on particles, it only need to prepare the initial entanglement states and only need to measure single particles. It is shown that the participants will not leak their private information by security analysis.

Cryptanalysis and Improvement of Quantum Private Comparison Protocol Based on Bell Entangled States

Recently, Liu et al. [Commun. Theor. Phys. 57 (2012) 583] proposed a quantum private comparison protocol based on entanglement swapping of Bell states, which aims to securely compare the equality of two participants' information with the help of a semi-honest third party (TP). However, the present study points out there is a fatal loophole in Liu et al.'s protocol, and TP can make Bell-basis measurement to know all the participants' secret inputs without being detected. To fix the problem, a simple solution, which uses one-time eavesdropper checking with decoy photons instead of twice eavesdropper checking with Bell states, is demonstrated. Compared with the original protocol, it not only reduces the Bell states consumption but also simplifies the protocol steps.

A Quantum Private Comparison Protocol with Splitting Information Carriers

Based on quantum information splitting and reconstruction, we present a quantum private comparison (QPC) protocol, enabling two distrustful parties (Alice and Bob) to compare the equality of their information without revealing the information content. In this protocol, the information carriers are split into two wave packets by a beam splitter (BS), which is owned by a semi-honest third party Trent, and then they are sent to Alice and Bob, respectively. Alice and Bob encodes their secret information on the received wave packets. Only the superimposition of the two wave packets in Trent’s site can reveal the compared result. Compared with the QPC protocols using entangled states, the information carriers used in our protocol is single-photon pulse, which reduces the difficulty of realization in practical. In addition, our protocol is feasible with the present techniques since only linear optical components, BS, single-photon detector, phase shifter (PS) and switcher (SWT) are required. The security of the protocol is ensured by principles on the phenomenon of quantum interference. And through the security analysis it shows that the protocol is secure and resists against the well-known attacks.

Multi-party quantum private comparison protocol with $$n$$ n -level entangled states

In this paper, two multi-party quantum private comparison (MQPC) protocols are proposed in distributed mode and traveling mode, respectively. Compared with the first MQPC protocol, which pays attention to compare between arbitrary two participants, our protocols focus on the comparison of equality for $$n$$n participants with a more reasonable assumption of the third party. Through executing our protocols once, it is easy to get if $$n$$n participants' secrets are same or not. In addition, our protocols are proved to be secure against the attacks from both outside attackers and dishonest participants.

Fault-tolerant quantum cryptographic protocols with collective detection over the collective amplitude damping channel

In this paper, a quantum key distribution (QKD) protocol, which can be immune to collective amplitude damping noise, is proposed with collective detection strategy. Then a multi-party quantum secret sharing (MQSS) protocol and a quantum private comparison (QPC) protocol are introduced as two applications of the proposed QKD protocol. Except for one participant who is responsible for preparing and measuring quantum states, the rest of the users in each of these protocols only need to perform certain unitary operations due to the utilization of collective detection. Therefore, in addition to the advantage of being secure against collective amplitude damping noise, the proposed protocols still have the advantages of higher qubit efficiency and lower cost for implementation. Moreover, the security of these protocols is guaranteed by theorems on quantum operation discrimination.

Improvement on "an efficient protocol for the quantum private comparison of equality with W state"

A quantum private comparison (QPC) protocol based on W states [W. Liu et al., Opt. Commun.284, 3160 (2011)] has pointed out there is a flaw of information leak [Y. B. Li et al., Eur. Phys. J. D.66, 110 (2012)]. In order to solve the problem, a special kind of W-class state is introduced, and its construction framework of quantum circuits is sketched. Based on this kind of W-class states, an improvement on Liu et al.'s protocol is presented. Analysis shows the improvement can not only hold the characteristics of original protocol, but also avoid the information leak that Li et al. pointed out.

Quantum Private Comparison Protocol with W States

We propose a secure quantum protocol for comparing the equality of information with the help of a semi-honest third party (Trent). Our protocol utilizes the triplet W states, and the single-particle measurement. The technique for preparing W state is mature, which ensures the utility of our protocol. The security of our protocol with respect to both outsider attack and participant attack is discussed. Any information about the private information, the comparison result will not be leaked out, even the third party cannot know these information.

Secure Quantum Private Comparison of Equality Based on Asymmetric W State

Recently, Liu et al. [Opt. Commun. 284, 3160, 2011] proposed a protocol for quantum private comparison of equality (QPCE) based on sym- metric W state. However, Li et al. [Eur. Phys. J. D. 66, 110, 2012] pointed out that there is a flaw of information leak, and they proposed a new protocol based on EPR pairs. While examining these two protocols, we find that there exists a same flaw: the third party (TP) can know the comparison result. In this paper, through introducing and constructing a special class of asymmet- ric W state, a secure QPCE protocol based on this asymmetric W state is presented. Analysis shows the present protocol can not only effectively avoid the information leak found by Li et al, but also ensure TP would not get any information about the comparison result.

Differential phase shift quantum private comparison

A novel quantum private comparison protocol based on a differential phase shift scheme is presented in this paper. In our protocol, two distrustful participants can compare the equality of information with the help of a semi-honest third party. Taking advantages of differential phase shift scheme, this protocol employs weak coherent pulses instead of single photons and can be implemented without expensive and impractical quantum devices, such as entangled photon source and quantum memory. Therefore, it is simpler and more flexible than previous protocols. Moreover, in principle, nearly 100 % qubit efficiency can be achieved because all photon counts obtained by TP contribute to the comparison. The correctness and security of the protocol are also discussed.

Quantum private comparison with d-level single-particle states

In this paper, a quantum private comparison protocol with d-level single-particle states is proposed. In the protocol, a semi-honest third party is introduced to help two participants compare the size relationship of their secrets without revealing them to any other people. It is shown that the protocol is secure in theory. Moreover, the security of the protocol in real circumstance is also discussed.

Multi-party Quantum Private Comparison Protocol Using d-Dimensional Basis States Without Entanglement Swapping

We present a new multi-party quantum private comparison protocol based on d-dimensional basis states. Different from previous protocols, our protocol have some advantages. n parties can determine wether their private information are equal or not in one time execution of our protocol. Without using the entangled character of d-dimensional basis states, we only need to perform the local unitary operation on particles to encode the information and to get the comparison result. We also discuss that our protocol can withstand various kinds of outside attacks and participant attacks.

A class of protocols for quantum private comparison based on the symmetry of states

In this paper, a class of protocols for quantum private comparison is investigated. The main feature is that the symmetry of quantum states is utilized. First of all, we design a new protocol for quantum private comparison via the $$\chi $$?-type state as a special example. Then, through the in-deep research and analysis on the quantum carrier, it is found that lots of quantum states with the symmetrical characteristic can be utilized to perform the protocol successfully. It is an attractive advantage in the practical application. What is more, two players are only required to be equipped with the unitary operation machines. It means that our protocols can easily be realized and have a broad scope of application. Finally, the analyses on the protocols' security, which are mainly ensured by the symmetry of quantum states and the property of the decoy state, are given in detail.

Erratum to: Same Initial States Attack in Yang et al.’s Quantum Private Comparison Protocol and the Improvement

Erratum to: Same Initial States Attack in Yang et al.’s Quantum Private Comparison Protocol and the Improvement

Comment on the “Quantum Private Comparison Protocol Based on Bell Entangled States”

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.

Quantum private comparison of equality protocol without a third party

This paper presents a novel quantum private comparison protocol that uses Einstein---Podolsky---Rosen pairs. The proposed protocol allows two parties to secretly compare their information without exposing their actual contents. The technique of entanglement swapping enables the comparison to be achieved without the help of a third party. Moreover, because the proposed protocol employs one-step transmission and decoy photons, it is secure against the various quantum attacks in existence thus far.

Same Initial States Attack in Yang et al.’s Quantum Private Comparison Protocol and the Improvement

In Yang et al.’s literatures (J. Phys. A: Math. 42, 055305, 2009; J. Phys. A: Math. 43, 209801, 2010), a quantum private comparison protocol based on Bell states and hash function is proposed, which aims to securely compare the equality of two participants’ information with the help of a dishonest third party (TP). However, this study will point out their protocol cannot resist a special kind of attack, TP’s same initial states attack, which is presented in this paper. That is, the dishonest TP can disturb the comparison result without being detected through preparing the same initial states. Finally, a simple improvement is given to avoid the attack.