Multi-party Quantum Private Comparison Protocol Research Articles

Multi-Party Quantum Private Comparison Based on Bell States.

Multi-party quantum private comparison (MQPC) assumes responsibility for overseeing the flow of data and communication among diverse entities, wherein it boasts powerful security capabilities that have garnered substantial attention. Most current MQPC protocols rely on difficult-to-prepare quantum states and are inefficient in their use of resources. In this paper, we propose a novel MQPC protocol without entanglement swapping, thereby building upon the assumption of an ideal channel. This protocol is based on Bell states, which simplifies implementation and addresses the challenges associated with using complex quantum states; it also enables the comparison of secret information by having a trusted party prepare and transmit encoded quantum sequences to participants, thereby facilitating efficient equality comparison among all parties. Our MQPC protocol showcased remarkable efficiency in comparison to existing protocols for quantum private comparison. Furthermore, the incorporation of decoy photon and shared key technologies made external and internal attacks ineffective, thereby ensuring the utmost security and integrity of the protocol.

Efficient multiparty quantum private comparison protocol based on single photons and rotation encryption

Efficient multiparty quantum private comparison protocol based on single photons and rotation encryption

Multi-party quantum private comparison of size relationship with two third parties based on d-dimensional Bell states

In this paper, we put forward a multi-party quantum private comparison (MQPC) protocol with two semi-honest third parties (TPs) by adopting -dimensional Bell states, which can judge the size relationship of private integers from more than two users within one execution of protocol. Each TP is permitted to misbehave on her own but cannot collude with others. In the proposed MQPC protocol, TPs are only required to apply -dimensional single-particle measurements rather than -dimensional Bell state measurements. There are no quantum entanglement swapping and unitary operations required in the proposed MQPC protocol. The security analysis validates that the proposed MQPC protocol can resist both the outside attacks and the participant attacks. The proposed MQPC protocol is adaptive for the case that users want to compare the size relationship of their private integers under the control of two supervisors. Furthermore, the proposed MQPC protocol can be used in the strange user environment, because there are not any communication and pre-shared key between each pair of users.

Improved multiparty quantum private comparison based on quantum homomorphic encryption

Quantum homomorphic encryption has obvious superiority in privacy protection. In this paper, we propose an improved multiparty quantum private comparison protocol based on quantum homomorphic encryption. Firstly, a trusted key center is introduced to securely assist the distribution of the encryption keys and update of decryption keys, while preventing a malicious server from launching an attack that announces a false result. It can significantly improve the security of the protocol while ensuring that all participants get the correct comparison results. Then, our protocol is different from the previous protocols that use the help of a semi-honest third-party. The third-party in our protocol can be almost dishonest and will faithfully perform the homomorphic evaluation on the encrypted data without decryption. Finally, by preparing single photons, multiple participants request homomorphic computations from an almost dishonest third-party in parallel and there is no need for detection of the decoy photon, which greatly reduces the consumption of quantum resources. In addition, the correctness of the protocol is verified by the IBM Q experimental platform.

Improvement of multi-party quantum private comparison protocol using d-dimensional basis states without entanglement swapping

Recently, Gu et al. (2019, arXiv:1907.02656) and Zhang et al. (Quantum Inf Process (2019)18:336) independently pointed out that in Yang et al.’s quantum summation protocol (Quantum Inf Process (2018) 17:129), the party in charge of preparing the initial quantum states is able to steal other parties’ private integer strings without being discovered by launching two special kinds of attack. In this paper, it is pointed out that in Liu et al.’s MQPC protocol, if the third party (TP) named Calvin launches the similar attacks, she can also steal the private secrets from n parties without being discovered. Then, two methods are put forward to avoid this drawback, i.e., the first one is to add the process of checking whether the quantum states shared among n parties are genuinely in the state of |W〉12⋯n while the second one is to encrypt the private secrets from n parties with a private key sequence shared among them beforehand.

Secure dynamic multiparty quantum private comparison

We propose a feasible and efficient dynamic multiparty quantum private comparison protocol that is fully secure against participant attacks. In the proposed scheme, two almost-dishonest third parties generate two random keys and send them to all participants. Every participant independently encrypts their private information with the encryption keys and sends it to the third parties. The third parties can analyze the equality of all or some participants’ secrets without gaining access to the secret information. New participants can dynamically join the protocol without the need for any additional conditions in the protocol. We provide detailed correctness and security analysis of the proposed protocol. Our security analysis of the proposed protocol against both inside and outside attacks proves that attackers cannot extract any secret information.

A New Multi-Party Quantum Private Comparison Protocol Based on Circle Model

Recently multi-party quantum private comparison (MQPC) has attracted more and more attentions in the research of quantum cryptography. In our paper, a new MQPC protocol has been proposed by encoding the compared secrets on the phase of n-level single photons. From the proposed protocol, a generic model named circle model can be summarized. With the help of a semi-honest third party (TP), it can be proved that our protocol is immune to the outside attack and dishonest participants’ (including TP) attack.

Circular Multi-Party Quantum Private Comparison with n-Level Single-Particle States

In this paper, a novel multi-party quantum private comparison (MQPC) protocol for equality comparison with n-level single-particle states is constructed, where the encoded particles are transmitted in a circular way. Here, n parties employ the qudit shifting operation to encode their private secrets and can compare the equality of their private secrets within one time execution of protocol. The proposed MQPC protocol can overcome both the outside attack and the participant attack. Specially, each party's secret can be kept unknown to other parties and the third party (TP).

Robust Multi-party Quantum Private Comparison Protocols Against the Collective Noise Based on Three-Qubit Entangled States

Recently, Ye and Ji constructed a multi-party quantum private comparison (MQPC) protocol with Bell entangled states (Sci. China Phys. Mech. Astron. 60(9), 090312, 2017). However, this protocol is only workable over an ideal quantum channel. In this paper, we take the collective noise channel into account and generalize Ye and Ji’s protocol into the ones against the collective-dephasing noise and the collective-rotation noise, respectively. Concretely, we use three-qubit entangled states instead of Bell states as the initial quantum states and employ the corresponding logical qubits immune to the collective noise instead of the physical qubits as the travelling particles. The output correctness and the security of the proposed robust MQPC protocols can be guaranteed.

Dynamic Multi-Party Quantum Private Comparison Protocol with Single Photons in Both Polarization and Spatial-Mode Degrees of Freedom

A dynamic quantum private comparison protocol based on the single photons in both polarization and spatial-mode degrees of freedom is proposed. In this protocol, any two parties of n(n ≥ 4) parties can compare their private information with the help of others n − 2 parties. And any party can join in the protocol to take part in the comparison of n parties. Correctness analysis shows that the proposed protocol can be used to compare their information correctly. Security analysis shows that the proposed protocol can resist the general active attacks from an outside eavesdropper. And it can overcomes the problem of information leakage.

Multi-Party Quantum Private Comparison Protocol Based on Entanglement Swapping of Bell Entangled States**Supported by the National Natural Science Foundation of China under Grant No. 61402407

Recently, Liu et al. proposed a two-party quantum private comparison (QPC) protocol using entanglement swapping of Bell entangled state (Commun. Theor. Phys. 57 (2012) 583). Subsequently Liu et al. pointed out that in Liu et al.'s protocol, the TP can extract the two users' secret inputs without being detected by launching the Bell-basis measurement attack, and suggested the corresponding improvement to mend this loophole (Commun. Theor. Phys. 62 (2014) 210). In this paper, we first point out the information leakage problem toward TP existing in both of the above two protocols, and then suggest the corresponding improvement by using the one-way hash function to encrypt the two users' secret inputs. We further put forward the three-party QPC protocol also based on entanglement swapping of Bell entangled state, and then validate its output correctness and its security in detail. Finally, we generalize the three-party QPC protocol into the multi-party case, which can accomplish arbitrary pair's comparison of equality among K users within one execution.

Multi-Party Quantum Private Comparison Protocol with an Almost-Dishonest Third Party using GHZ States

This article proposes an innovative quantum private comparison (QPC) protocol for n users using GHZ states, where an almost-dishonest third party (TP) is introduced to assist the participants for comparing their secrets. It is argued that as compared to the existing QPC protocols our proposed scheme has some considerable advantages. First, in the existing QPC protocols, the TP can only to determine whether all participants’ secrets are equal or not. Instead of that, in our proposed scheme a TP can even compare the secrets between any subsects of users. Second, since our proposed scheme is based on GHZ state; hence it can ensure higher efficiency as compared to other existing multi-party QPC protocols on d-dimension photons.

Multi-party quantum private comparison with an almost-dishonest third party

This article proposes the first multi-party quantum private comparison protocol with an almost-dishonest third party, where many participants can compare their secrets in either ascending or descending order without revealing any secret information to anyone. In order to do that, the participants need not to pre-share any secret key between them. As a consequence, the proposed scheme can be enforced in several environments such as multi-party ranking and multi-data ranking protocol.

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.

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.

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.

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.