Quantum Signature Protocols Research Articles

A secure and efficient identity-based quantum signature scheme

In recent years, identity-based quantum signature protocols have received much attention due to their unique advantages. Based on Bell states, we propose an efficient identity-based quantum signature scheme. In our scheme, the signer’s private key is generated from their identity information. The signer uses the private key and secret parameters to generate a signature for the verifier. The verifier, who possesses the identity information of the signer, can authenticate the signature. Our proposed scheme ensures signature non-forgeability and non-repudiation. In addition, the protocol does not require the preparation of long-term quantum memory or the performance of quantum swap tests, making it more efficient than previous schemes.

Semi-quantum bi-signature scheme based on Bell states

Currently, quantum signature protocols assume that all participants in the protocol (signers, verifiers, and arbitrators) should exhibit quantum capabilities. If quantum devices are lacking, the quantum signature protocol cannot be implemented. However, quantum devices are not widely used, and not all users can own quantum devices. Boyer et al. first proposed the concept of the semi-quantum environment. Zhao et al. proposed a semi-quantum signature protocol with double signers based on the W state. Yang et al. discovered that in the semi-quantum signature protocol with double signers developed by Zhao et al., an internal attacker could launch an impersonation attack during the verification and signature stages to capture the private key and use it to impersonate the user’s identity. In addition, the eavesdropper can obtain all the secret information of the signers by performing a man-in-the-middle attack. All three attack modes can pass the eavesdropping check. Hence, if these security problems are not solved, the signature of the semi-quantum signature protocol with double signers proposed by Zhao et al. cannot be completed safely. Therefore, based on Bell states, a new semi-quantum signature protocol of double signers was developed in this study. The proposed protocol not only resists impersonation attacks and man-in-the-middle attacks but also resists other common attack modes.

High fidelity quantum blind dual-signature protocols

This work proposes two kinds of fault tolerant quantum blind dual-signature (QBDS) protocols with photon quartets, which are robust against the collective-dephasing noise and collective-rotation noise, respectively. In the protocols, the initial information needs to be signed by the message owner in addition to the signer, which will be well suitable for application in some E-payment and E-government systems that require the message owner to provide authentication information. Both QBDS protocols are constructed with logical qubits which are immune to the collective noise, thereby the protocols can provide higher communication fidelity with respect to the existing quantum signature protocols. Furthermore, the protocols had been proved to be secure against some individual eavesdropping attacks. Meanwhile, the protocols satisfy the characteristics of quantum blind signature (QBS) protocols such as unforgeability, undeniability and blindness.

A Quantum Dual-Signature Protocol Based on SNOP States without Trusted Participant.

Quantum dual-signature means that two signed quantum messages are combined and expected to be sent to two different recipients. A quantum signature requires the cooperation of two verifiers to complete the whole verification process. As an important quantum signature aspect, the trusted third party is introduced to the current protocols, which affects the practicability of the quantum signature protocols. In this paper, we propose a quantum dual-signature protocol without arbitrator and entanglement for the first time. In the proposed protocol, two independent verifiers are introduced, here they may be dishonest but not collaborate. Furthermore, strongly nonlocal orthogonal product states are used to preserve the protocol security, i.e., no one can deny or forge a valid signature, even though some of them conspired. Compared with existing quantum signature protocols, this protocol does not require a trusted third party and entanglement resources.

Semi-Quantum Proxy Signature Scheme with Quantum Walk-Based Teleportation

Quantum secure communication network is in the stage of rapid construction. As classical networks, we researchers also need to develop different practical quantum protocols for different application scenarios in quantum communication network. However, complex quantum operations and expensive quantum resource preparation seriously hinder the practical development of quantum communication networks. A variety of quantum signature protocols play an important role in quantum communications; however, these protocols also face the same problems described above. In this paper, we propose a semi-quantum proxy signature scheme with quantum walk-based teleportation to solve these problems. Proxy signer TP as the quantum participant and original signer Alice is the classical participant. We introduce quantum walk teleportation to generate quantum entanglement resource naturally in signature phase, which seems more in line with the reality of quantum communication networks. Security analysis show that this scheme meets all the security requirement of quantum proxy signature protocol, and the qubit efficiency analysis also proves this protocol has better practical value.

Arbitration quantum signature protocol based on XOR encryption

Quantum signature is a branch of quantum cryptography that draws on the design ideas of classic digital signatures, and uses the basic principles of quantum mechanics to achieve the integrity, authenticity and nonrepudiation of quantum information. Among them, arbitration quantum signature (AQS) plays a very important role. In this paper, we proposed an AQS protocol based on XOR encryption. Unlike other protocols, a quantum one-time pad encryption method or chain-type CNOT encryption method is abandoned. The proposed protocol is designed based on the three-particle GHZ state combined with the idea of classical XOR encryption, with CNOT operations used to encrypt quantum messages and quantum signatures. A security analysis of the proposed protocol reveals that the proposed protocol can satisfy the AQS requirements of unforgeability and nonrepudiation.

Arbitrated quantum signature protocol with boson sampling-based random unitary encryption

For signing quantum messages, the arbitrated quantum signature (AQS) has been widely investigated to date. However, most of the existing AQS protocols are susceptible to different aspects of disavowal and forgery attacks due to the use of quantum one time pad (QOTP) encryption featuring the encryption manner with qubit by qubit and the commutative property of Pauli operations. We develop an AQS protocol with boson sampling-based random unitary encryption. The unique encryption is used to encrypt the message copy (ciphertext) to produce the signature, which can circumvent the drawbacks of the QOTP encryption and stand against the signer Alice’s disavowal and the verifier Bob’s forgery attacks including existential forgery under known message attacks. The employment of a random array via the public board can prevent Bob’s repudiation attacks on the receipt and the integrality of the signature. The quantum walk-based teleportation is applied to teleport the message copy from Alice to Bob, which can avoid preparing the essential entanglement resource beforehand. Security analyses and discussions show that our AQS protocol is with impossibility of disavowal from Alice and Bob and impossibility of forgery from anyone.

An arbitrated quantum signature protocol using rotation and permutation operators

The existing improved arbitrated quantum signature (AQS) protocols still have some security problems. First, the security of one AQS protocol is analysed, including existential forgery attack and the signer’s disavowal attack. To resist these attacks, a novel AQS protocol using rotation and permutation operators is proposed. And the analysis shows that the protocol can resist all the known forgery attacks and the signer’s disavowal attacks.

Arbitrated Quantum Signature Protocol with Asymmetric Key Based on Qubit Block Encryption

Here, The new arbitrated quantum signature (AQS) protocol assisted by asymmetric key based on qubit block encryption algorithm is given. Interestingly, our protocol with the asymmetric key can be easily extended to multi-party verification. Unlike all previous quantum works on arbitrated quantum signature, the encryption algorithm of the pre-sented protocol is qubit block encryption. Since, the proposed protocol has a better performance in resisting existential forgery attack. In addi-tion, with the help of the arbitrator, it can be proved that our protocol is secure.

Universal quantum encryption for quantum signature using the swap test

We suggest a universal quantum encryption scheme suitable for use in quantum signature. The verifier in a variety of quantum signature protocols usually checks for the falsification of the quantum signature state pair by using a swap test. However, these quantum signature protocols are not secure against existential forgery attacks; We prove that the universal quantum encryption scheme proposed in this paper is secure against this type of forgery because it uses the non-(anti)commutativity of an arbitrary unitary operator. In addition, we demonstrate its use in a quantum signature. Moreover, the optimization of this encryption in comparison with other encryption schemes is presented.

The Security Problems in Some Novel Arbitrated Quantum Signature Protocols

With the development of quantum signature, two improved arbitrated quantum signature(AQS) protocols have been presented with different quantum encryptions. In this paper, some security loopholes during the two AQS protocols are proposed. In the enhanced arbitrated quantum signature(EAQS) protocol, though the signer is not able to deny his signature, the receiver can still forge some valid signatures. In the chaos-based arbitrated quantum signature(CAQS) protocol, the receiver can forge a valid signature without being caught, and the signer can also deny her signature after the signing phase. Finally, some potential improved ideas are discussed.

An improved arbitrated quantum signature protocol based on the key-controlled chained CNOT encryption

In this paper, a new quantum encryption based on the key-controlled chained CNOT operations, which is named KCCC encryption, is proposed. With the KCCC encryption, an improved arbitrated quantum signature (AQS) protocol is presented. Compared with the existing protocols, our protocol can effectively prevent forgery attacks and disavowal attacks. Moreover, only single state is required in the protocol. We hope it is helpful to further research in the design of AQS protocols in future.

Fault-tolerant quantum blind signature protocols against collective noise

This work proposes two fault-tolerant quantum blind signature protocols based on the entanglement swapping of logical Bell states, which are robust against two kinds of collective noises: the collective-dephasing noise and the collective-rotation noise, respectively. Both of the quantum blind signature protocols are constructed from four-qubit decoherence-free (DF) states, i.e., logical Bell qubits. The initial message is encoded on the logical Bell qubits with logical unitary operations, which will not destroy the anti-noise trait of the logical Bell qubits. Based on the fundamental property of quantum entanglement swapping, the receiver simply performs two Bell-state measurements (rather than four-qubit joint measurements) on the logical Bell qubits to verify the signature, which makes the protocols more convenient in a practical application. Different from the existing quantum signature protocols, our protocols can offer the high fidelity of quantum communication with the employment of logical qubits. Moreover, we hereinafter prove the security of the protocols against some individual eavesdropping attacks, and we show that our protocols have the characteristics of unforgeability, undeniability and blindness.

Quantum broadcasting multiple blind signature with constant size

Using quantum homomorphic signature in quantum network, we propose a quantum broadcasting multiple blind signature scheme. Different from classical signature and current quantum signature schemes, the multi-signature proposed in our scheme is not generated by simply putting the individual signatures together, but by aggregating the individual signatures based on homomorphic property. Therefore, the size of the multi-signature is constant. Furthermore, based on a wide range of investigation for the security of existing quantum signature protocols, our protocol is designed to resist possible forgery attacks against signature and message from the various attack sources and disavowal attacks from participants.

Multiparty quantum signature schemes

Digital signatures are widely used in electronic communications to secure important tasks such as financial transactions, software updates, and legal contracts. The signature schemes that are in use today are based on public-key cryptography and derive their security from computational assumptions. However, it is possible to construct unconditionally secure signature protocols. In particular, using quantum communication, it is possible to construct signature schemes with security based on fundamental principles of quantum mechanics. Several quantum signature protocols have been proposed, but none of them has been explicitly generalised to more than three participants, and their security goals have not been formally defined. Here, we first extend the security definitions of Swanson and Stinson [1] so that they can apply also to the quantum case, and introduce a formal definition of transferability based on different verification levels. We then prove several properties that multiparty signature protocols with informationtheoretic security – quantum or classical – must satisfy in order to achieve their security goals. We also express two existing quantum signature protocols with three parties in the security framework we have introduced. Finally, we generalize a quantum signature protocol given in [2] to the multiparty case, proving its security against forging, repudiation and non-transferability. Notably, this protocol can be implemented using any pointto-point quantum key distribution network and therefore is ready to be experimentally demonstrated.

Arbitrated Quantum Signature Scheme with Continuous-Variable Coherent States

Motivated by the revealing features of the continuous-variable (CV) quantum cryptography, we suggest an arbitrated quantum signature (AQS) protocol with CV coherent states. It involves three participants, i.e., the signer Alice, the verifier Bob and the arbitrator Charlie who is trustworthy by Alice and Bob. Three phases initializing phase, signing phase and verifying phase are included in our protocol. The security of the signature scheme is guaranteed by the generation of the shared keys via the CV-based quantum key distribution (CV-QKD) and the implementation process of the CV-based quantum teleportation as well. Security analysis demonstrates that the signature can be neither forged by anyone nor disavowed by the receiver and signer. Moreover, the authenticity and integrality of the transmitted messages can be ensured. The paper shows that a potential high-speed quantum signature scheme with high detection efficiency and repetition rate can be realized when compared to the discrete-variable (DV) quantum signature scheme attributing to the well characteristics of CV-QKD.

An arbitrated quantum signature protocol based on the chained CNOT operations encryption

At present, the encryption scheme used by most arbitrated quantum signature (AQS) protocols is quantum one-time pad (QOTP) which encrypts data qubit by qubit. Though QOTP can achieve high security for data encryption, it is not suitable for AQS. There are many attacks on AQS using QOTP. In this paper, we propose an AQS protocol based on another encryption scheme called the chained CNOT operations, which encrypts quantum message ensemble. Our protocol preserves all merits in the similar AQS schemes and has better security. Security analysis shows that our protocol cannot be forged and disavowed under the existing attacks.

Security of the arbitrated quantum signature protocols revisited

Recently, much attention has been paid to the study of arbitrated quantum signature (AQS). Among these studies, the cryptanalysis of some AQS protocols and a series of improved ideas have been proposed. Compared with the previous analysis, we present a security criterion, which can judge whether an AQS protocol is able to prevent the receiver (i.e. one participant in the signature protocol) from forging a legal signature. According to our results, it can be seen that most AQS protocols which are based on the Zeng and Keitel (ZK) model are susceptible to a forgery attack. Furthermore, we present an improved idea of the ZK protocol. Finally, some supplement discussions and several interesting topics are provided.

Arbitrated Quantum Signature Scheme with Message Bits Intertwined

To solve a common problem existing in most of the present arbitrated quantum signature (AQS) protocols, a new AQS scheme is proposed, in which the security is based on both quantum cryptographic techniques and some ideas in classical cryptography. With message bits intertwined in the proposed scheme, an eavesdropper cannot modify the transmitted message for his own benefit. This scheme provides higher security.

Security Weaknesses in Arbitrated Quantum Signature Protocols

Arbitrated quantum signature (AQS) is a cryptographic scenario in which the sender (signer), Alice, generates the signature of a message and then a receiver (verifier), Bob, can verify the signature with the help of a trusted arbitrator, Trent. In this paper, we point out there exist some security weaknesses in two AQS protocols. Our analysis shows Alice can successfully disavow any of her signatures by a simple attack in the first protocol. Furthermore, we study the security weaknesses of the second protocol from the aspects of forgery and disavowal. Some potential improvements of this kind of protocols are given. We also design a new method to authenticate a signature or a message, which makes AQS protocols immune to Alice’s disavowal attack and Bob’s forgery attack effectively.