This study proposes the first multiparty-to-multiparty mediated quantum secret sharing (M2M-MQSS) protocol within a restricted quantum environment. Unlike existing fully quantum secret sharing (QSS) protocols, this protocol allows protocol participants with limited quantum capabilities—including (1) measuring a single qubit in the Z-basis and (2) performing a single-qubit unitary operation, Hadamard operation—to participate, significantly reducing implementation costs. By employing one-way qubit transmission, the proposed MMQSS protocol not only simplifies the quantum communication process but also effectively defends against quantum Trojan horse attacks. The correctness and security analyses demonstrate that the proposed M2M-MQSS protocol is robust against various well-known attack strategies. Simulation experiments confirm the feasibility of the protocol for various numbers of participants. It maintains high levels of efficiency and security even as the number of participants increases. Moreover, compared with existing protocols, the proposed M2M-MQSS protocol lowers the barrier to practical quantum communication deployment by reducing the quantum resources required for protocol participants.
This study proposes the first multiparty-to-multiparty mediated quantum secret sharing (M2M-MQSS) protocol within a restricted quantum environment. Unlike existing fully quantum secret sharing (QSS) protocols, this protocol allows protocol participants with limited quantum capabilities—including (1) measuring a single qubit in the Z-basis and (2) performing a single-qubit unitary operation, Hadamard operation—to participate, significantly reducing implementation costs. By employing one-way qubit transmission, the proposed MMQSS protocol not only simplifies the quantum communication process but also effectively defends against quantum Trojan horse attacks. The correctness and security analyses demonstrate that the proposed M2M-MQSS protocol is robust against various well-known attack strategies. Simulation experiments confirm the feasibility of the protocol for various numbers of participants. It maintains high levels of efficiency and security even as the number of participants increases. Moreover, compared with existing protocols, the proposed M2M-MQSS protocol lowers the barrier to practical quantum communication deployment by reducing the quantum resources required for protocol participants.
Abstract The multiparty‐mediated quantum secret sharing (MQSS) protocol proposed by Tsai et al. [Quantum Inf. Process., 2022, 21, 63] allows n restricted users with limited quantum capabilities to share secret information using a dishonest third party with full quantum capabilities. Although the MQSS protocol allows restricted users to achieve secret sharing with lightweight quantum capabilities, the qubit efficiency of this protocol can be further improved. Therefore, this study proposes a measurement property of the graph state to design an efficient mediated quantum secret‐sharing protocol in the same quantum environment as that of Tsai et al.’s protocol. The proposed MQSS protocol not only inherits the lightweight property of Tsai et al.’s protocol but also improves the qubit efficiency of Tsai et al.’s protocol by times. Security analysis is performed to show that the proposed MQSS protocol can avoid collective, collusion, and Trojan horse attacks. Furthermore, this study uses quantum network simulation software to implement Tsai et al.’s protocol and the proposed protocol to prove the feasibility of the proposed MQSS protocol and show that it is more efficient than Tsai et al.’s protocol.
Typical multiparty semi-quantum secret sharing (MSQSS) protocols require the dealer to possess full quantum capabilities, while the classical users usually need to perform three operations. To address this practical limitation, this paper introduces a new mediated MSQSS protocol that enables Alice, a classical user, to share a secret with [Formula: see text] classical Bobs, with the assistance of an untrusted third party (TP) who may attempt any possible attack to steal Alice’s secret. Furthermore, the classical participants require only two capabilities instead of three, namely: (a) performing measurements in the [Formula: see text] basis; and (b) reordering qubits. The proposed scheme offers significant advantages over existing mediated QSS protocols: (1) It is the first mediated SQSS protocol to adopt single qubits, instead of entangled states, as the quantum resource, which makes it more practical and easier to implement; (2) It achieves higher qubit efficiency. Security analysis also demonstrates that the protocol is secure against well-known attacks.
This study proposes a multiparty single-photon semi-quantum secret sharing (SQSS) protocol to simultaneously improve quantum bit (qubit) efficiency and practical feasibility. Existing quantum secret sharing protocols typically assume that all participants possess full quantum capabilities, which limits their deployment in real-world environments. To address this issue, the proposed protocol was designed using a semi-quantum model, allowing N agents with limited quantum capabilities to participate in the secret-sharing process. In terms of efficiency, the proposed protocol employs single photons as quantum resources and is analyzed under a unified definition of qubit efficiency. The results show that the qubit efficiency of the proposed protocol reaches 2N1 , which is comparable to the best recent quantum secret sharing protocols and outperforms most existing SQSS methods. Unlike certain protocols in which qubit efficiency decreases exponentially with the number of participants, the quantum resource consumption of the proposed protocol increases linearly with the number of agents. Consequently, its qubit efficiency decreases proportionally to N1 , rather than exponentially, providing better scalability as the number of agents increases. In terms of security, the protocol is analyzed against several attack models, including intercept-resend, entangle-and-measure, collective, and collusion attacks. The analysis shows that an adversary cannot obtain useful information without detection under these attacks, demonstrating the robustness of the proposed protocol.
Abstract Quantum secret sharing (QSS) is a significant branch of quantum cryptography and can be widely used in various applications. Quantum secret sharing schemes can be developed by utilizing different features of quantum mechanics, and quantum secure direct communication (QSDC) is an effective way to achieve secret sharing using single qubits. The utilization of QSDC offers certain benefits, such as low cost, high security, and great potential for implementation with current technologies. However, the purpose of QSDC is different from that of QSS, which causes some vulnerabilities, such as dishonest participant attacks. We discover two critical factors that affect the security of traditional protocols. Firstly, they skip a few steps from the QSDC protocol to the QSS protocol. Secondly, the participants have different privileges. This can lead to participants with more privileges engaging in potential attack behavior. In light of these issues, this study proposes a new multiparty QSS scheme to address these vulnerabilities. The proposed protocol ensures the independence of each participant and grants them equal privileges. Analysis results demonstrate that it can defend against malicious attackers, retain the advantages of the QSDC protocol, and further reduce transmission costs. It achieves an excellent balance between security and performance.
The aim of quantum secret sharing, as one of most promising components of quantum cryptograph, is one-to-multiparty secret communication based on the principles of quantum mechanics. In this paper, an efficient multiparty quantum secret sharing protocol in a high-dimensional quantum system using a single qudit is proposed. Each participant's shadow is encoded on a single qudit via a measuring basis encryption method, which avoids the waste of qudits caused by basis reconciliation. Security analysis indicates that the proposed protocol is immune to general attacks, such as the measure-resend attack, entangle-and-measure attack and Trojan horse attack. Compared to former protocols, the proposed protocol only needs to perform the single-qudit measurement operation, and can share the predetermined dits instead of random bits or dits.
We analyzed the security of the multiparty quantum secret sharing (MQSS) protocol recently proposed by Zhang, Li, and Man [Phys. Rev. A 71, 044301 (2005)] and found that this protocol is secure for any other eavesdropper except for the agent Bob who prepares the quantum signals as he can attack the quantum communication with a Trojan horse. That is, Bob replaces the single-photon signal with a multiphoton one and the other agent Charlie cannot find this cheating as she does not measure the photons before they run back from the boss Alice, which reveals that this MQSS protocol is not secure for Bob. Finally, we present a possible improvement of the MQSS protocol security with two single-photon measurements and four unitary operations.