Abstract With the continuous development of quantum technology, researchers are constantly improving the research on quantum signatures. In the public-key cryptosystem, a quantum group signature scheme based on four-particle Cluster states is proposed. In this scheme, the four-particle Cluster states are used as quantum channels. The signer randomly generates his private key according to the public key generated by the group manager, and uses the private key to sign. The verifier uses the public key to verify the signature. The features of the scheme are as follows: the public key and private key can be reused, thus reducing the number of keys that need to be saved by the communication parties; The length of the message to be signed does not need to be the same as the length of the public and private keys, which increases the flexibility of the signature; The random sequence is used in the signature process to ensure the unpredictability of the key, thus improving the security of the scheme; The scheme has unforgeability and non-repudiation.
Abstract With the continuous development of quantum technology, researchers are constantly improving the research on quantum signatures. In the public-key cryptosystem, a quantum group signature scheme based on four-particle Cluster states is proposed. In this scheme, the four-particle Cluster states are used as quantum channels. The signer randomly generates his private key according to the public key generated by the group manager, and uses the private key to sign. The verifier uses the public key to verify the signature. The features of the scheme are as follows: the public key and private key can be reused, thus reducing the number of keys that need to be saved by the communication parties; The length of the message to be signed does not need to be the same as the length of the public and private keys, which increases the flexibility of the signature; The random sequence is used in the signature process to ensure the unpredictability of the key, thus improving the security of the scheme; The scheme has unforgeability and non-repudiation.
Abstract With the continuous development of quantum technology, the quantum signature as an application of quantum cryptography has received great attention. In this paper, we propose a public-key quantum group blind signature scheme based on single-qubit rotations. In this scheme, the group manager generates a public key. Each group member randomly generates his own private key according to the public key. The signer uses his private key and random sequence to generate the signature. The verifier uses the public key to verify the correctness of the quantum signature. The public and private keys can be reused, which simplifies the key management of the signature system. In this scheme, the random sequence is used to enhance the security of the scheme. At the same time, the quantum efficiency is improved by using single-qubit rotations. The security analysis shows that our scheme can ensure the security of the keys, the unforgeability and the non-deniability of the signature.
Abstract With the development of cloud computing in recent years, homomorphic signatures have become a research hotspot in modern cryptography. This article proposes a quantum homomorphic signature scheme with verifiable identity based on four-particle Cluster states, starting from the identity verification of the signers. Compared with Shang’s scheme (Shang et al 2015 Quantum Inf. Process. 14 393–410), our scheme uses four-particle Cluster states as quantum channels and achieves identity verification of the signers through the use of X operation and quantum measurement techniques. Meanwhile, our scheme extends the length of message M to 2n bits and uses random numbers during the signature process, which makes the scheme more secure. Security analysis shows that our scheme can ensure the security of the keys and the unforgeability of the signatures.
operators, a new quantum signature scheme is proposed. In our scheme, the signer's private key is generated by a trusted private key generator (PKG), while the identity information of the signer is used as the corresponding public key. Both of the private key and public key of the signer are classical bit strings, which can be easily stored and reused. Given a quantum signature, anyone can verify the validity of the quantum signature with the signer's identity. Therefore, our scheme is a public-key quantum signature without a digital certificate, which has the merits of an identity-based cryptosystem and can simplify the key management of the quantum signature system. On the other hand, our scheme need not use any quantum swap test during the signature verification phase. Furthermore, by the signature proof, our scheme can arbitrate the potential disputation of losing quantum signature, which cannot be arbitrated in most of the quantum signature schemes. So our scheme has the property of strong non-repudiation. It also has the security properties of information-theoretic security, unforgeability, etc. Our scheme can achieve a high efficiency of 70%. Therefore, our quantum signature scheme is more secure, practicable, and efficient than the similar schemes.
Abstract With the rapid development of computer and internet technology, quantum signature plays an extremely important role in modern secure communication. Quantum homomorphic aggregate signature, as an important guarantee of quantum signature, plays a significant role in reducing storage, communication, and computing costs. This article draws on the idea of quantum multi-party summation and proposes a quantum homomorphic aggregate signature scheme based on quantum Fourier transform. Our scheme uses n-particle entangled states as quantum channels, with different particles of each entangled state sent separately. This ensures secure transmission of signatures and messages with fewer entangled particles during transmission, further improving the efficiency of quantum signatures. Meanwhile, our scheme generates private keys for each participating party by randomly constructing key generation matrixes. Different signers perform quantum Fourier transforms and basis exchange operations on entangled particles based on different messages and private keys to generate signatures. In addition, the aggregator does not need to measure and verify the signature particles after receiving signatures from different signers, and the group addition operation process has additive homomorphism. Security analysis shows that our scheme has unforgeability, non-repudiation, and can resist various attacks such as entanglement measurement attacks, intercept-resend attacks, private key sequence attacks, and internal attacks by aggregator.
Based on the Hadamard operator and Bell states, an identity-based public-key quantum signature scheme is proposed. In our scheme, the signer’s identity is used as her public key. Her private keys are generated by the trusted private key generator (PKG). Given a quantum signature, the verifier can verify the validity of the quantum signature by the signer’s identity information without any public-key certificate. So, our quantum signature has the advantages of the identity-based signature system. On the other hand, in our scheme, it need not use the long-term quantum memory. The verifier need not perform any quantum swap test or state comparison algorithm. What is more, our quantum signature is secure against PKG’s forgery attack. And the disputation of losing quantum signature can be arbitrated by PKG. Therefore, our scheme is relatively more practical and efficient than the similar schemes.
Abstract With the advancement of the new generation of information technology in recent years, quantum digital signatures have been widely concerned. Among them, quantum threshold group signatures have become a hot research field due to their advantages such as low cost and strong scalability. Therefore, in this paper, we propose an identity-verifiable quantum threshold group signature scheme based on three-particle GHZ states. The characteristics of the scheme are as follows. The signers can reconstruct the key K for signature’s generation and verification by using the Shamir threshold secret sharing scheme. A quantum signature is generated by performing controlled-not operations, von Neumann measurements, and quantum Fourier transform. When the signature is verified, only classical hash values need to be compared, without comparing quantum states. Identity verification is performed between participants by using hash functions. The efficiency of the scheme is improved by using super-dense coding. Security analysis shows that our scheme is unforgeable and undeniable.