Dynamic quantum secret sharing

Kuo-Chun Tseng, Wei-Lin Lee, Chi‐Yuan Chen +1 more

Abstract With the rapid development of quantum computing, traditional encryption methods face growing security threats. Quantum Secret Sharing (QSS) has emerged as a promising solution, using quantum principles to improve communication security and prevent internal and external attacks. This study proposes a new (t, n) Threshold Quantum Secret Sharing (TQSS) protocol based on single-qubit unitary operations and Lagrange interpolation. The protocol allows secret reconstruction without third-party or dealer assistance and remains efficient even when some participants are absent. To address more complex real-world scenarios, we extend our previously proposed (t, n) TQSS protocol into a Conditional Dynamic TQSS (CDTQSS). This approach uses resource-based share splitting to allow new participants to join without requiring the dealer to redistribute information. However, the protocol is ‘conditional’ because existing participants must take on extra responsibility-they must assist in generating shares for new members and also participate in the secret reconstruction process together with them. The protocol maintains strong security, reduces resource consumption, and offers better flexibility, making it well-suited for practical and dynamic quantum communication needs.

Heng-Yue Jia, Qiaoyan Wen, Fei Gao +2 more

Jian-Qiu Li, Ming‐Ming Wang

Abstract Numerous high-quality quantum secret sharing (QSS) protocols have been proposed as integral components of quantum cryptography. However, only a limited number effectively integrate both dynamic and verifiable characteristics. This paper proposes a verifiable dynamic (t, n) QSS protocol based on the asymmetric binary polynomial and the d-dimensional Bell states. In the protocol, the dealer can find out the internal fraudsters by verifying whether an agent has used a correct share. The agents can also verify the correctness of the shares provided by the dealer. Besides, the dealer has the capability to independently adding or revoking of agents without requiring assistance from other agents. Furthermore, the protocol requires at least t agents to recover the secret, which makes the proposed protocol more flexible and practical than existing protocols. Our protocol shows good robustness against the intercept-and-resend, the entangle-and-measure, the internal, and the dishonest revoked agent attacks.

김상겸

Hua‐Lei Yin, Jianyu SHEN, Nuo Chen +1 more

Quantum secret sharing (QSS), as a quantum extension of classical secret sharing, uses the basic principles of quantum mechanics to share information safely among multiple parties, providing a new paradigm for information security. As a key foundation for secure multiparty quantum communication and distributed quantum computing, QSS has attracted considerable attention since its emergence. Currently, research in this field includes both classical and quantum scenarios, and continuous progress has been made in both theoretical and experimental aspects. This paper first reviews the current development of QSS for classical information. In this regard, significant and parallel progress has been made in both discrete-variable QSS and continuous-variable QSS. The QSS protocols for sharing classical information, from entangled states to single photons and then to coherent light, have been continuously optimized to better utilize available resources and achieve more efficient implementation under current technological conditions. Meanwhile, round-robin, measurement-device-independent, and other protocols have been steadily improving the security of QSS. Next, one will focus on QSS scheme for quantum secrets, which begins with the symmetry of access structures and introduces basic (k, n) threshold protocols, dynamic schemes that support adaptive agent groups, and symmetric quantum information splitting through entanglement. It further introduces hierarchical quantum secret sharing schemes for asymmetric splitting of quantum information. Considering practical laboratory conditions of quantum states as resources, an overall discussion is conducted on quantum secret sharing with graph states. Afterwards, the design of a continuous-variable scheme for quantum secret sharing is outlined, and entanglement state sharing and quantum teleportation between multiple senders and receivers are introduced. Finally, this review discusses and outlines the future development directions of QSS, thereby inspiring readers to further study and explore the relevant subjects.

Ri‐Gui Zhou, Xiaoxue Zhang, Lin-Tao Du