Quantum Tagging with Cryptographically Secure Tags

Adrian Kent, William J. Munro, Timothy P. Spiller

We define the task of quantum tagging, that is, authenticating the classical location of a classical tagging device by sending and receiving quantum signals from suitably located distant sites, in an environment controlled by an adversary whose quantum information processing and transmitting power is unbounded. We define simple security models for this task and briefly discuss alternatives. We illustrate the pitfalls of naive quantum cryptographic reasoning in this context by describing several protocols which at first sight appear unconditionally secure but which, as we show, can in fact be broken by teleportation-based attacks. We also describe some protocols which cannot be broken by these specific attacks, but do not prove they are unconditionally secure. We review the history of quantum tagging protocols, and show that protocols previously proposed by Malaney and Chandran et al. are provably insecure.

Prabhanjan Ananth, Rolando L. La Placa

George Cowperthwaite, Adrian Kent, Damián Pitalúa-García

We discuss protocols for quantum position verification schemes based on the standard quantum cryptographic assumption that a tagging device can keep classical data secure [Kent, 2011]. Our schemes use a classical key replenished by quantum key distribution. The position verification requires no quantum communication or quantum information processing. The security of classical data makes the schemes secure against non-local spoofing attacks that apply to schemes that do not use secure tags. The schemes are practical with current technology and allow for errors and losses. We describe how a proof-of-principle demonstration might be carried out.

Song Yuan Yan

Dagmar Bruß, Tim Meyer

Xiangjun Xin, Xiaolin Hua, Chaoyang Li +1 more

Quantum authentication protocol can be used to authenticate classical messages in a secure manner. In this paper, by using the cryptographic hash function and non-orthogonal qubits, a quantum authentication protocol of classical messages is proposed. In our protocol, the classical messages and their corresponding tags are encoded as nonorthogonal qubits. The message receiver decodes the classical messages and their corresponding tags from the received qubits by using the authentication key. To verify the validity of the received classical messages, the message receiver verifies whether the hash values of the decoded classical messages are equal to the corresponding tags. Our scheme can be proved to be secure against forgery attack and measurement attack. On the other hand, the authentication key is a binary string, which can be securely obtained and easily saved. What is more, because the authentication key remains secure after executing the authentication protocol, it provides the possibility of reusing the authentication key.