Quantum Private Communication with an Anonymous Sender

Jiawei Liu, Qing-Xia Mu, Qingle Wang +2 more

Abstract Anonymous quantum communication (AQC) enables the secure transmission of classical and quantum messages while preserving the anonymity of the sender, receiver, or both. Qudits, quantum states with more advantages than qubits in terms of information transmission rate and eavesdropping detection, offer promising capabilities. In this paper, we propose a verifiable AQC (VAQC) protocol utilizing d-level single-particle states, establishing anonymous entanglement between a public sender and an anonymous receiver. By using quantum teleportation, the public sender can transmit private information to his/her chosen anonymous receiver. The verifiable function of the proposed protocol guarantees the legitimacy of all participants’ identities and verifies the correctness of the anonymous entanglement. Furthermore, we demonstrate that the proposed VAQC protocol satisfies the requirements of correctness, anonymity, and security. The proposed VAQC protocol exhibits extensibility and can be extended to enable private communication between an anonymous sender and an anonymous receiver, as well as anonymous entanglement among multiple participants. This work lays the foundation for practical applications in achieving d-level anonymous entanglement and anonymous transmission of qudits.

Srijani Das, Manasi Patra, Tuhin Paul +2 more

Anonymity is a fundamental cryptographic primitive that hides the identities of both senders and receivers during message transmission over a network. Classical protocols cannot provide information-theoretic security for such task, and existing quantum approaches typically depend on classical subroutines and multiple private channels, thereby weakening their security in fully adversarial settings. In this work, we introduce the first fully quantum protocol for anonymous communication in realistic quantum networks with a device-independent security proof.

Guihua Zeng

Gilles Brassard A, Anne Broadbent, Joseph F. Fitzsimons +2 more

Jan Bouda, Josef Šprojcar

While many scenarios of anonymous communication can be solved by various famous classical techniques including mix nets or dining cryptographers (DC), an abundant amount of anonymous tasks remains open. In this paper, we present a solution to one such task. Our protocol serves as a private communication channel for quantum messages while ensuring that both the sender and the receiver stay anonymous in a set of all parties. Our protocol is a continuation of our previous work on anonymous transmission of quantum information. The protocol does not require trusted parties, and is secure against an active adversary. It can also withstand denial of service attacks. The protocol exhibits an advantage of quantum resources over classical because no classical solution is known (in the same security settings). Entanglement swapping technique is used to create "symmetry" in the protocol, which makes it very transparent and easier to analyze. The security analysis we present is heavily based on our previous work on quantum anonymous communication. The task we implement is also a nice illustration of a cryptographic task where two parties in a multi-party protocol can be dishonest at the same time, but are not cooperating.

Gilles Brassard A, Anne Broadbent, Joseph F. Fitzsimons +2 more