Digital certificate offers an efficient way to realize the access authentication which safeguards the first line of secure communication. In this paper, we propose an access authentication scheme with digital certificates based on post-quantum standards published by the National Institute of Standards and Technology for quantum communication networks. Specifically, we experimentally demonstrate the secure access authentication of the quantum channel by verifying the signatures encoded in quantum states in a quantum secure direct communication network. Only the post-quantum digital signature algorithm is needed in the experiment. Together with secure relays, we envision the establishment of a large-scale quantum-secure communication network in the future.
Digital certificate offers an efficient way to realize the access authentication which safeguards the first line of secure communication. In this paper, we propose an access authentication scheme with digital certificates based on post-quantum standards published by the National Institute of Standards and Technology for quantum communication networks. Specifically, we experimentally demonstrate the secure access authentication of the quantum channel by verifying the signatures encoded in quantum states in a quantum secure direct communication network. Only the post-quantum digital signature algorithm is needed in the experiment. Together with secure relays, we envision the establishment of a large-scale quantum-secure communication network in the future.
Quantum key distribution (QKD) can provide information theoretically secure key exchange even in the era of quantum computer. However, QKD requires the classical channel to be authenticated, and the current method is pre-sharing symmetric keys. For a QKD network of n users, this method requires Cn2=n(n−1)/2 pairs of symmetric keys to realize pairwise interconnection. In contrast, with the help of mature public key infrastructure (PKI) and post-quantum cryptography (PQC) with quantum resistant security, each user only needs to apply for a digital certificate from certificate authority (CA) to achieve efficient and secure authentication for QKD. We only need to assume the short-term security of the PQC algorithm to achieve the long-term security of the distributed keys. Here, we experimentally verified the feasibility, efficiency and stability of the PQC algorithm in QKD authentication, and demonstrated the advantages when new users join the QKD network. Using PQC authentication we only need to believe the CA is safe, rather than all trusted relays. QKD combined with PQC authentication will greatly promote and extend the application prospects of quantum safe communication.
Abstract Quantum key distribution (QKD) can provide information theoretically secure key exchange even in the era of quantum computers. However, QKD requires the classical channel to be authenticated, the current method for which is pre-sharing symmetric keys. For a QKD network of n users, this method requires Cn2=n(n−1)/2 C n 2 = n ( n − 1 ) / 2 pairs of symmetric keys to realize pairwise interconnection. In contrast, with the help of a mature public key infrastructure (PKI) and post-quantum cryptography (PQC) with quantum-resistant security, each user only needs to apply for one digital certificate from a certificate authority (CA) to achieve efficient and secure authentication for QKD. We need to assume only the short-term security of the PQC algorithm to achieve long-term security of the distributed keys. Here, we experimentally verified the feasibility, efficiency, and stability of the PQC algorithm in QKD authentication, and demonstrated the advantages when new users join the QKD network. Using the PQC public-key infrastructure, the nodes need to mutually trust only the CA to authenticate each other. QKD combined with PQC authentication will greatly promote and extend the application prospects of quantum-safe communication.
In mobile networking, specifically in 5G networking, embedded SIM (eSIM) does not rely on the hardware chips to deliver the core network’s public key as traditional SIM cards do. Instead, eSIM utilizes remote digital certificates enabled by Public Key Infrastructure (PKI). In this research, we study the post-quantum transition of eSIM-based mobile networking by applying and incorporating the post-quantum ciphers to the digital certificates and authentication. While building on the existing mutual authentication between the user equipment and core network, we build quantum resistance in the digital signatures used for the digital certificate and authentication so that they are secure against quantum-computing attackers. We implement our scheme using the NIST-standardized post-quantum ciphers to evaluate the computing/time and battery/power overheads, which are important for resource-constrained mobile devices. We compare the post-quantum ciphers with the current quantum-vulnerable ciphers and show that the lattice-based schemes have comparable or even better overhead performances.
Abstract Cryptography promises four information security objectives, namely, confidentiality, integrity, authenticity and non-repudiation, to support trillions of transactions annually in the digital economy. Efficient digital signatures, ensuring integrity, authenticity and non-repudiation of data with information-theoretical security are highly urgent and intractable open problems in cryptography. Here, we propose a high-efficiency quantum digital signature (QDS) protocol using asymmetric quantum keys acquired via secret sharing, one-time universal2 hashing and a one-time pad. We just need to use a 384-bit key to sign documents of lengths up to 264 with a security bound of 10−19. If a one-megabit document is signed, the signature efficiency is improved by more than 108 times compared with previous QDS protocols. Furthermore, we build the first all-in-one quantum secure network integrating information-theoretically secure communication, digital signatures, secret sharing and conference key agreement and experimentally demonstrate this signature efficiency advantage. Our work completes the cryptography toolbox of the four information security objectives.
Guaranteeing nonrepudiation, unforgeability as well as transferability of a signature is one of the most vital safeguards in today's e-commerce era. Based on fundamental laws of quantum physics, quantum digital signature (QDS) aims to provide information-theoretic security for this cryptographic task. However, up to date, the previously proposed QDS protocols are impractical due to various challenging problems and most importantly, the requirement of authenticated (secure) quantum channels between participants. Here, we present the first quantum digital signature protocol that removes the assumption of authenticated quantum channels while remaining secure against the collective attacks. Besides, our QDS protocol can be practically implemented over more than 100 km under current mature technology as used in quantum key distribution.
Digital signature schemes play an important role in the security of communication systems, ensuring authentication, integrity, and non-repudiation of messages. Classical digital signature schemes are widely used in communication systems but are not secure against quantum attacks, thereby necessitating the use of post-quantum cryptographic techniques. Recently, lattice-based digital signatures were proposed as efficient and quantum-resistant digital signatures. However, the lattice-based digital signatures are not effective in detecting eavesdropping or interception of messages during transmission. Quantum authentication techniques, on the other hand, are effective in detecting eavesdropping or interception of messages during transmission by utilizing the measurement disturbance principle of quantum mechanics. In this paper, we propose a hybrid quantum-classical digital signature scheme that combines the post-quantum security of lattice-based digital signatures with the capability of detecting eavesdropping or interception of messages during transmission by utilizing the quantum authentication techniques based on the entanglement principle of quantum mechanics. We discuss the system model, protocol, security, and performance evaluation of the proposed scheme in terms of computational and communication complexities. The proposed scheme is effective in the context of future communication systems that require security guarantees, such as quantum communication networks, critical infrastructures, and blockchain-based authentication systems.