Abstract Most existing blind quantum computation protocols involve a client and a server or multiple servers. The case of multiple clients needs to be explored as well, but it becomes less secure as more people are involved. Authentication helps to solve the problem by enabling clients and servers to verify each other’s identity. In this paper, a multi-party verifiable blind quantum computation protocol with mutual authenti-cation is proposed which consists of three phases. Firstly, we improve the method for generating keys. Based on this, a deterministic method is proposed to generate authentication keys. Then, the client and the server perform mutual authentication. Finally, the only requirement for the client is to perform the gate S to accomplish the quantum computing task. The proposed protocol can resist both insider and outsider attacks, ensuring the legitimacy of clients and servers in a quantum network. The protocol further also limits the client’s quantum power and allows the client to verify the accuracy of the calculation results.
Abstract Most existing blind quantum computation protocols involve a client and a server or multiple servers. The case of multiple clients needs to be explored as well, but it becomes less secure as more people are involved. Authentication helps to solve the problem by enabling clients and servers to verify each other’s identity. In this paper, a multi-party verifiable blind quantum computation protocol with mutual authenti-cation is proposed which consists of three phases. Firstly, we improve the method for generating keys. Based on this, a deterministic method is proposed to generate authentication keys. Then, the client and the server perform mutual authentication. Finally, the only requirement for the client is to perform the gate S to accomplish the quantum computing task. The proposed protocol can resist both insider and outsider attacks, ensuring the legitimacy of clients and servers in a quantum network. The protocol further also limits the client’s quantum power and allows the client to verify the accuracy of the calculation results.
Blind quantum computation (BQC) provides a solution for clients with limited quantum capabilities to delegate their quantum computational tasks to remote quantum servers while keeping their own data private. In this paper, we first propose three multi-party verifiable blind quantum computation (MPVBQC) protocols, each of which can handle one type of clients with certain simple quantum capabilities such as making single-qubit measurements, preparing single qubits, or performing a few single-qubit gates. Then a flexible and hybrid MPVBQC framework for multi-type clients in quantum networks is given by combining the three proposed MPVBQC protocols. It simultaneously allows at least three types of clients in quantum networks to achieve BQC depending on their own quantum devices. Furthermore, all the proposed protocols can achieve identity authentication, resist both insider and outsider attacks, and be verifiable which means that the clients can verify the correctness of their computational results.
Quantum computing has considerable advantages in solving some problems over its classical counterpart. Currently various physical systems are developed to construct quantum computers but it is still challenging and the first use of quantum computers may adopt the cloud style. Blind quantum computing (BQC) provides a solution for clients with limited quantum capabilities to delegate their quantum computation to remote quantum servers while keeping input, output, and even algorithm private. In this paper, we propose three multi-party verifiable blind quantum computing (VBQC) protocols with identity authentication to handle clients with varying quantum capabilities in quantum networks, such as those who can just make measurements, prepare single qubits, or perform a few single-qubit gates. They are client-friendly and flexible since the clients can achieve BQC depending on their own quantum devices and resist both insider outsider attacks in quantum networks. Furthermore, all the three proposed protocols are verifiable, namely that the clients can verify the correctness of their calculations.
Abstract Blind quantum computing enables quantum-limited clients to securely access untrusted quantum servers. This paper proposes a three-party verifiable blind quantum computing protocol with separated input and function ownership, where Alice holds the private input, Bob holds the target function, and Charlie performs the delegated quantum computation, with the result released only to Alice. Alice and Bob first establish a shared key using BB84. Under the measurement-based quantum computing framework, a secure two-party computation protocol is then used to jointly generate adaptive blinded measurement instructions, eliminating the need for Bob to transmit quantum states to Charlie. A hidden dummy-trap mechanism is further incorporated to verify malicious server behavior. Under the honest-but-curious client model without client-server collusion, the protocol protects input and function privacy while ensuring computation blindness, shared-key security, and verifiability. Most quantum operations are performed by Charlie, while the clients require only limited quantum capabilities.
Abstract Blind Quantum Computing (BQC) is a protocol proposed in recent years to tackle the practical need where users want to perform quantum computing tasks but lack the necessary capabilities, and thus delegate the work to quantum computing platforms while keeping their data secure throughout the process. Besides, its characteristics provide new ways for secure multi-party computation, helping multiple untrusted users to compute together securely. Most existing secure multi-party computation protocol based on blind quantum computing rely on DT(G) states to perform joint computation. However, this can lead to security risks because one client has too much authority, and these schemes also lack generality. In this paper, a secure multi-party computation protocol is proposed based on brickwork states. By exploiting and optimizing the properties of these states, the security issues in joint client computation are solved and centralized authority is avoided. Meanwhile, it reflects the interactive mode in multi-party computation. The proposed protocol effectively improves the generality of computation.
Universal blind quantum computing allows users with minimal quantum resources to delegate a quantum computation to a remote quantum server, while keeping intrinsically hidden input, algorithm, and outcome. State-of-art experimental demonstrations of such a protocol have only involved one client. However, an increasing number of multi-party algorithms, e.g. federated machine learning, require the collaboration of multiple clients to carry out a given joint computation. In this work, we propose and experimentally demonstrate a lightweight multi-client blind quantum computation protocol based on a recently proposed linear quantum network configuration (Qline). Our protocol originality resides in three main strengths: scalability, since we eliminate the need for each client to have its own trusted source or measurement device, low-loss, by optimizing the orchestration of classical communication between each client and server through fast classical electronic control, and compatibility with distributed architectures while remaining intact even against correlated attacks of server nodes and malicious clients.
Blind quantum computation (BQC) enables a client without enough quantum power to delegate his quantum computation to a quantum server, while keeping the input data, the algorithm and the result unknown to the server. In the studies of practical BQC protocol, an important problem is how to reduce the quantum requirement of the client. Multi-server BQC protocols have been proposed to solve this problem. We review the double-server and triple-server protocols [Li et al., Phys. Rev. A 89, 040302(R) (2014)], and propose a modified double-server BQC protocol with a trusted center. In our protocol, the servers are allowed to communicate mutually, and the client is completely classical. Furthermore, our double-server protocol can be modified into a single-server protocol by simply combining the two servers. Compared with the triple-server protocol, our double-server and single-server protocols are more simple and the client is not required to have the ability to access quantum channel. So our protocols are more practical when quantum computer is applied in the `cloud' model.