For the existing quantum threshold signature protocols based on entangled state, it is difficult to prepare quantum resources. Meanwhile, for the quantum threshold signature protocols based on single-particle sequence, it has disadvantages of high computation and communication consumptions. To remedy these shortcomings, in this paper, we proposed a quantum threshold signature protocol based on mutual unbiased basis (MUB). In initialization stage, the message owner Alice prepares a quantum sequence [Formula: see text] with length of [Formula: see text], each single particle in [Formula: see text] is chosen from MUBs. The signature key is generated by Alice using threshold secret-sharing distribution algorithm, the verification key is generated by [Formula: see text] signers via threshold secret-sharing recovery algorithm. In signature generation phase, the signers execute the signature algorithm sequentially until the last signer and then obtain the final signature, next send it to verifier. In signature verification phase, the verifier Ver verifies the original message and the final signature using the verification key. Security analysis shows that the proposed protocol can resist interception-forgery attack, collusion attack and denial attack. Performance analysis shows that the proposed protocol is easier to prepare quantum resources than similar protocols, and has lower communication consumption, especially when the number of signers [Formula: see text] and increase gradually. Finally, the correctness of the proposed protocol is verified by simulation experiment on quantum cloud platform.
For the existing quantum threshold signature protocols based on entangled state, it is difficult to prepare quantum resources. Meanwhile, for the quantum threshold signature protocols based on single-particle sequence, it has disadvantages of high computation and communication consumptions. To remedy these shortcomings, in this paper, we proposed a quantum threshold signature protocol based on mutual unbiased basis (MUB). In initialization stage, the message owner Alice prepares a quantum sequence [Formula: see text] with length of [Formula: see text], each single particle in [Formula: see text] is chosen from MUBs. The signature key is generated by Alice using threshold secret-sharing distribution algorithm, the verification key is generated by [Formula: see text] signers via threshold secret-sharing recovery algorithm. In signature generation phase, the signers execute the signature algorithm sequentially until the last signer and then obtain the final signature, next send it to verifier. In signature verification phase, the verifier Ver verifies the original message and the final signature using the verification key. Security analysis shows that the proposed protocol can resist interception-forgery attack, collusion attack and denial attack. Performance analysis shows that the proposed protocol is easier to prepare quantum resources than similar protocols, and has lower communication consumption, especially when the number of signers [Formula: see text] and increase gradually. Finally, the correctness of the proposed protocol is verified by simulation experiment on quantum cloud platform.
Most of the classical designated verifier signature schemes are insecure against quantum adversary. In this paper, a quantum signature scheme for the designated verifier is proposed. In our scheme, during the initialization phase, the partners share secret keys by performing the quantum key distribution protocol. On the other hand, by performing the quantum direct communication protocol, the key generator center shares secret keys with the signer and the designated verifier, respectively. The key generator center generates a particle sequence of Bell state and distributes the particles between the signer and the designated verifier. During the signature generation phase, the signer encrypts the particle sequence by the secret keys and Hardmard operators. After that, the signer performs the controlled unitary operations on the encrypted particle sequence so as to generate the quantum signature. The designated verifier can simulate the quantum signature by performing the same symmetric signing steps as that performed by the original signer. Hence, the quantum signature signed by the true signer is the same as the one simulated by the receiver, which makes our scheme possess the designated properties. During the signature verification phase, the designated verifier performs the controlled unitary operations on the quantum signature and obtains the quantum ciphertexts. After that, the designated verifier decrypts the quantum ciphertexts by the symmetric secret keys and Hardmard operators so that the quantum signature can be verified. Our signature is secure against forgery attack, inter-resending attacks and Trojan horse attack. Because the trace distance between the density operators of different quantum signatures is zero, the information-theoretical security of our quantum signature scheme can be proved. The unconditionally secure quantum key distribution protocol and the one-time pad encryption algorithm can guarantee the security of the secret keys shared by the partners. What is more, the security assumption about the key generation center is weak. That is, it is not necessary to assume that the key generation center should be fully trusted. On the other hand, in our scheme, the quantum one-way function is not used. To generate a quantum signature, the signer need not prepare for entangled particle sequence. To verify a quantum signature, the verifier need not apply any state comparison to the received particles. The qubit efficiency is 100%. Therefore, our scheme has the advantages in the security and efficiency over the other quantum signature schemes for the designated verifier.
In this paper, we propose a new quantum signature protocol with identity-based threshold multiple verifiers. In this protocol, first, the signature process combines the HMAC hash function with the participant identity to realize the compression encryption of the signature message, at the same time, the signature particles are encoded and generated by selecting the 3-particle GHZ state of the [Formula: see text] spatially localizable distinguished (LOCC), which avoids the complex entanglement operation and effectively improves the signature efficiency; second, it takes at least t verifying members of the set of valid verifications specified by the signer to verify the validity of the final signature, which increases the utility of the signature protocol in multi-verification scenarios; finally, the security analysis shows that the proposed threshold multiparty verifiable quantum signature protocol scheme can resist entanglement measurement attacks, intercept retransmission attacks, and at the same time be unforgeable, nonrepudiable, and traceable. Most importantly, the protocol does not require Quantum One-Way Function (QOWF), Quantum State Swap Test (SWAP), and has no complex entanglement operations. Therefore, the proposed scheme is more efficient than similar multiparty signature protocols.
Most (k, n) threshold quantum secret sharing protocols are fully quantum. The message receivers must be equipped with complex quantum devices so as to prepare various quantum resources and perform complex quantum operations, which may affect the practice of these protocols. On the other hand, the qubit efficiency of most (k, n) threshold quantum secret sharing protocols is not more than 1/2. To simplify the (k, n) threshold quantum secret sharing protocol and improve its practice and qubit efficiency, a new (k, n) threshold secret sharing protocol with semi-quantum properties is proposed. In this protocol, the dealer prepares decoy particles and sends them to the receivers. The receivers insert particles carrying secret information along with Z-basis decoy particles into the received particle sequence to generate mixed-particle sequences, which are returned to the dealer. The dealer measures the received particle sequences to check for eavesdropping and establishes shared secret keys with the receivers. With the shared secret keys, the dealer distributes the secret pieces among the receivers using Shamir’s secret sharing scheme. Multiple secret messages can be recovered by k or more receivers. The qubit efficiency of our protocol is k/n. For an (n, n) threshold protocol, the qubit efficiency would be 100%. The proposed scheme is based on single particles without using any entangled system. Therefore, its quantum resources are relatively easy to prepare. Receivers must only prepare simple Z-basis qubits. Its semi-quantum properties enhance practice implementation. The proposed protocol has robust security against various types of attacks, including eavesdropping, internal, and collusion attacks. Furthermore, it can resist the unitary attack, which is seldom analyzed in other protocols.
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.
Quantum secret sharing (QSS) is an important branch of quantum cryptography. Identity authentication is a significant means to achieve information protection, which can effectively confirm the identity information of both communication parties. Due to the importance of information security, more and more communications require identity authentication. We propose a d-level (t,n) threshold QSS scheme in which both sides of the communication use mutually unbiased bases for mutual identity authentication. In the secret recovery phase, the sharing of secrets that only the participant holds will not be disclosed or transmitted. Therefore, external eavesdroppers will not get any information about secrets at this phase. This protocol is more secure, effective, and practical. Security analysis shows that this scheme can effectively resist intercept–resend attacks, entangle–measure attacks, collusion attacks, and forgery attacks.
In the most arbitrated quantum signatures (AQSs), the signers and verifiers need to perform the quantum key distribution protocols or some other protocols to share secret keys before signing a signature. In some schemes, the entangle states, which are not easily implemented, have to be prepared and distributed among the partners. Based on single photon and one-way functions, a new AQS scheme without entangled states is proposed. In our scheme, the signer generates a quantum signature on the classical message with his/her private key and the one-way function. The arbitrator communicates with the signer through a classical unencrypted channel. The signer and verifier need not perform the key distribution protocol before signing a message. On the other hand, without entangled states, our scheme can reduce the complexity of implementation. Then, our scheme is more efficient than the similar schemes. At the same time, our scheme is secure against forgery attack and disavowal attack.