The emerging quantum technology has highlighted the necessity for secure and efficient secret sharing in quantum networks. In this paper, we introduce a verifiable multiparty counterfactual quantum secret sharing (QSS) protocol, enhancing security and efficiency. This QSS protocol utilizes a low-depth quantum circuit to encrypt and decrypt information, which comprises a unitary operator constructed using a preshared secret key. To ensure the robustness and verifiability of the shared secret key, the protocol imposes constraints on the participants with the Chinese remainder theorem. The most significant advantage of our proposed QSS protocol is incorporating counterfactual communication, which considerably enhances the scheme’s security by enabling exchange-free information sharing among participants, thereby minimizing the risk of eavesdropping or intercept-and-resend attacks. Furthermore, we incorporate a weighted-threshold mechanism that provides flexibility, enabling diverse use cases to design security protocols for quantum networks. The security analysis of the counterfactual QSS protocol and its implementation on IBM Quantum computers reveals strong resilience to internal and external attacks, along with high efficiency and robustness, making it effective for quantum encryption in the noisy intermediate-scale quantum era.
The emerging quantum technology has highlighted the necessity for secure and efficient secret sharing in quantum networks. In this paper, we introduce a verifiable multiparty counterfactual quantum secret sharing (QSS) protocol, enhancing security and efficiency. This QSS protocol utilizes a low-depth quantum circuit to encrypt and decrypt information, which comprises a unitary operator constructed using a preshared secret key. To ensure the robustness and verifiability of the shared secret key, the protocol imposes constraints on the participants with the Chinese remainder theorem. The most significant advantage of our proposed QSS protocol is incorporating counterfactual communication, which considerably enhances the scheme’s security by enabling exchange-free information sharing among participants, thereby minimizing the risk of eavesdropping or intercept-and-resend attacks. Furthermore, we incorporate a weighted-threshold mechanism that provides flexibility, enabling diverse use cases to design security protocols for quantum networks. The security analysis of the counterfactual QSS protocol and its implementation on IBM Quantum computers reveals strong resilience to internal and external attacks, along with high efficiency and robustness, making it effective for quantum encryption in the noisy intermediate-scale quantum era.
Secret sharing is a widely-used security protocol and cryptographic primitive in which all people cooperate to restore encrypted information. The characteristics of a quantum field guarantee the security of information; therefore, many researchers are interested in quantum cryptography and quantum secret sharing (QSS) is an important research topic. However, most traditional QSS methods are complex and difficult to implement. In addition, most traditional QSS schemes share classical information, not quantum information which makes them inefficient to transfer and share information. In a weighted threshold QSS method, each participant has each own weight, but assigning weights usually costs multiple quantum states. Quantum state consumption will therefore increase with the weight. It is inefficient and difficult, and therefore not able to successfully build a suitable agreement. The proposed method is the first attempt to build multiparty weighted threshold QSS method using single quantum particles combine with the Chinese remainder theorem (CRT) and phase shift operation. The proposed scheme allows each participant has its own weight and the dealer can encode a quantum state with the phase shift operation. The dividing and recovery characteristics of CRT offer a simple approach to distribute partial keys. The reversibility of phase shift operation can encode and decode the secret. The proposed weighted threshold QSS scheme presents the security analysis of external attacks and internal attacks. Furthermore, the efficiency analysis shows that our method is more efficient, flexible, and simpler to implement than traditional methods.
Abstract Threshold quantum secret sharing is a cryptography technique for dividing and reconstructing secret information. The dealer shares a secret based on quantum mechanics principles, and a subset of participants cooperate to recover that secret. For example, in k , n quantum threshold scheme and n , n quantum threshold scheme, the former can only reconstruct the secret when at least k shares are collected. The latter requires all n shares to be collected to reconstruct the secret. However, in real scenarios, the priority of participant identities may vary. In order to meet the actual needs of participants with different rights, this paper proposes a w , ω , n quantum secret sharing (QSS) scheme. When the sum of participants’ weights w is greater than or equal to a threshold ω, they can cooperate to reconstruct the secret. In order to achieve this, this paper uses the entangled state of single particles and constructs a verifiable QSS scheme based on the Chinese remainder theorem. Significantly, in case of a dishonest participant, the dealer can delete the participant before recovering the secret to ensure the security of the communication. This scheme is more flexible than other threshold protocols. At the same time, it reduces the communication cost of the participants. In addition, security analysis shows that the scheme resists typical external and internal attacks.
With the rise of quantum computing, traditional cryptography is facing serious threats. Secret sharing, as an important primitive of cryptography, is also affected. Because secret sharing is widely used in many fields, researchers have started to explore quantum secret sharing (QSS). QSS uses basic principles of quantum mechanics to provide strong security and can protect against both eavesdropping and malicious attacks. However, most existing QSS studies focus on specific situations and lack the flexibility needed for complex multiparty environments. In this work, we propose a general QSS framework that can be applied to different scenarios. We first design a basic [Formula: see text] QSS protocol, and then extend it to support multiparty communication and dynamic changes in participants. Our security analysis shows that the proposed method keeps strong security, uses fewer resources, and works independently without the need for a trusted third party (TP). This protocol offers a unified solution that can meet different application needs and provides a new approach to handling diverse QSS tasks more efficiently.
Quantum secret sharing (QSS) is a cryptographic protocol that utilizes fundamental principles of quantum mechanics to securely distribute and reconstruct secret information among multiple participants. Most existing protocols rely on entangled states (such as Bell and GHZ states), but in practical applications. The preparation of entangled state is constrained by a short quantum coherence time, low state fidelity, etc., which makes it difficult to implement entangled resource-dependent QSS protocols. In this work, a novel practical and verifiable multi-party QSS protocol is proposed based on orthogonal product states, which are easier to prepare than entangled states. During the protocol preparation stage, the secret distributor first converts pre-shared classical secret information into the corresponding orthogonal product states according to the encoding rules, and pre-shares a communication key with participants via quantum key distribution (QKD), which is used to hide the initial quantum sequence information through subsequent particle transformation operations. After preparing the orthogonal product states, the distributor reorganizes the particles by position, extracting particles at the same position from each state to form new sequences, shuffling their order, then applying Hadamard operations using a pre-shared key, inserting decoy particles, and sending the sequences to the participants. After receiving it, participants conduct eavesdropping detection, use the same key for the inverse transformations, retain one particle from each sequence, and sequentially pass the remaining particles until the last participant receives a complete set, triggering state verification with the arbiter distributor. If the verification is successful, the particles will be returned to the first participant and the return stage will follow the same procedure. Only after both the transmission and return stage verifications have passed, will the distributor reveal the initial particle positions, allowing participants to collaboratively reconstruct the secret. In the protocol, the secret distributor acts as an arbitrator to verify the particle state information together with participants at designated points (the end of the transmission stage and the end of the return stage) in order to determine whether the particle-state information is error-free during transmission. If the verification fails at either stage, the protocol will be terminated immediately. Meanwhile, considering that the number of participants may change during the execution of the protocol, a dynamic scheme for personnel changes is designed to ensure the flexibility of the protocol. Through the analysis of possible internal and external attacks, It can be proven that our protocol can effectively resist the existing common attack. Using Qiskit simulation experiments, the core quantum procedures of the protocol can be successfully modeled. The experimental results provide strong computational validation of the theoretical feasibility of the protocol.
Abstract In the field of quantum cryptography, Quantum Secret Sharing (QSS) holds substantial importance, with identity authentication emerging as a key strategy for safeguarding information. It efficiently certifies the identification of both persons involved in the conversation, which contributes to increased security measures. Our proposal, a (m, n) threshold Quantum Secret Sharing (QSS) scheme introduces a unique approach to mutual identity authentication, utilizing mutually unbiased bases. During the secret recovery phase, the scheme ensures that secrets exclusively held by participants remain undisclosed and are not transmitted, reinforcing the security of the communication process. As a result, external eavesdroppers are left empty-handed in their attempt to access information about secrets during this phase. Our protocol surpasses in terms of security, effectiveness, and practicality, proving its resilience against intercept–resend attacks, collusion attacks, collective attacks, and forgery attacks according to a comprehensive security analysis.
Abstract Quantum secret sharing (QSS) plays a crucial role in quantum cryptography as a privacy preserving scheme. Designing an efficient QSS protocol requires addressing three key challenges: 1) dynamic agent membership (handling agents joining or leaving during execution), 2) adversarial resilience (ensuring robustness against dishonest agents), and 3) practical optimization (improving computational and communication efficiency while minimizing implementation cost). In this paper, a verifiable dynamic threshold QSS (VDQSS) protocol with authentication capability is proposed. The protocol employs single particles for both authentication and share distribution, combining homogeneous linear recursion (HLR) with mutually unbiased bases (MUBs) to reconstruct multiple secrets. This approach significantly enhances security while reducing protocol complexity. The correctness and practicality of the protocol are validated through experimental simulations. Analytical results demonstrate its robustness against common attacks, providing reliable security guarantees for quantum communications. Compared to existing QSS protocols, the protocol offers enhanced simplicity and practical applicability.