A novel practical quantum secret sharing protocol is proposed to share a private key between one and many parties based on four single-qubit states. The qubit capacity of this protocol is high due to the absence of bitwise exclusive OR of qubits' measuring results. It is also feasible with present-day technology, even when a great many participants are engaged, and secure against several common attacks. Besides, this protocol can be directly extended to deal with the many-to-many situation.
A novel practical quantum secret sharing protocol is proposed to share a private key between one and many parties based on four single-qubit states. The qubit capacity of this protocol is high due to the absence of bitwise exclusive OR of qubits' measuring results. It is also feasible with present-day technology, even when a great many participants are engaged, and secure against several common attacks. Besides, this protocol can be directly extended to deal with the many-to-many situation.
A novel quantum secret sharing scheme between one and many parties with four states is proposed. Different from existing schemes, the bit value of shared key in this scheme depends on the operations done by the receivers, say Bobs, not the preparer Alice, which is highly applicable in some cases. This paper also gives the definition of qubit capacity, in order to signify the relative amount of quantum resource needed in schemes. The analysis shows that the qubit capacity of our scheme is 1, which means it saves quantum resource due to the absence of entanglement and bitwise Exclusive OR operations on qubits' measuring results. Besides, this scheme has features of being convenient for receivers, feasible with current technology, and also secure against some common attacks.
In single-qubit quantum secret sharing, a secret is shared between N parties via manipulation and measurement of one qubit at a time. Each qubit is sent to all N parties in sequence; the secret is encoded in the first participant's preparation of the qubit state and the subsequent participants' choices of state rotation or measurement basis. We present a protocol for single-qubit quantum secret sharing using polarization entanglement of photon pairs produced in type-I spontaneous parametric downconversion. We investigate the protocol's security against eavesdropping attack under common experimental conditions: a lossy channel for photon transmission, and imperfect preparation of the initial qubit state. A protocol which exploits entanglement between photons, rather than simply polarization correlation, is more robustly secure. We implement the entanglement-based secret-sharing protocol with 87 secret-sharing fidelity, limited by the purity of the entangled state produced by our present apparatus. We demonstrate a photon-number splitting eavesdropping attack, which achieves no success against the entanglement-based protocol while showing the predicted rate of success against a correlation-based protocol.
Abstract Quantum secret sharing (QSS) is a significant branch of quantum cryptography and can be widely used in various applications. Quantum secret sharing schemes can be developed by utilizing different features of quantum mechanics, and quantum secure direct communication (QSDC) is an effective way to achieve secret sharing using single qubits. The utilization of QSDC offers certain benefits, such as low cost, high security, and great potential for implementation with current technologies. However, the purpose of QSDC is different from that of QSS, which causes some vulnerabilities, such as dishonest participant attacks. We discover two critical factors that affect the security of traditional protocols. Firstly, they skip a few steps from the QSDC protocol to the QSS protocol. Secondly, the participants have different privileges. This can lead to participants with more privileges engaging in potential attack behavior. In light of these issues, this study proposes a new multiparty QSS scheme to address these vulnerabilities. The proposed protocol ensures the independence of each participant and grants them equal privileges. Analysis results demonstrate that it can defend against malicious attackers, retain the advantages of the QSDC protocol, and further reduce transmission costs. It achieves an excellent balance between security and performance.
We propose a quantum secret sharing protocol between multiparty (m members in group 1) and multiparty (n members in group 2) using a sequence of single photons. These single photons are used directly to encode classical information in a quantum secret sharing process. In this protocol, all members in group 1 directly encode their respective keys on the states of single photons via unitary operations; then, the last one (the mth member of group 1) sends 1∕n of the resulting qubits to each of group 2. Thus the secret message shared by all members of group 1 is shared by all members of group 2 in such a way that no subset of each group is efficient to read the secret message, but the entire set (not only group 1 but also group 2) is. We also show that it is unconditionally secure. This protocol is feasible with present-day techniques.
In this paper, we propose an efficient multi-party quantum secret sharing scheme based on GHZ entangled state. The participants in this scheme are divided into two groups, and share secrets as a group. There is no need to exchange any measurement information between the two groups, reducing the security problems caused by the communication process. Each participant holds one particle from each GHZ state; it can be found that the particles of each GHZ state are related after measuring them, and the eavesdropping detection can detect external attacks based on this characteristic. Furthermore, since the participants within the two groups encode the measured particles, they can recover the same secrets. Security analysis shows that the protocol can resist the intercept-and-resend attack and entanglement measurement attack, and the simulation results show that the probability of an external attacker being detected is proportional to the amount of information he can obtain. Compared with the existing protocols, this proposed protocol is more secure, has less quantum resources and is more practical.
The need for secrecy and security is essential in communication. Secret sharing is a conventional protocol to distribute a secret message to a group of parties, who cannot access it individually but need to cooperate in order to decode it. While several variants of this protocol have been investigated, including realizations using quantum systems, the security of quantum secret sharing schemes against eavesdroppers and dishonest participants remained unproven. Here we establish an unconditional security proof for continuous variable entanglement-based quantum secret sharing schemes, in the limit of asymptotic keys and for an arbitrary number of players, by utilizing ideas from the recently developed one-sided device-independent approach to quantum key distribution. We demonstrate the practical feasibility of our scheme, which can be implemented by Gaussian states and homodyne measurements, with no need for ideal single-photon sources or quantum memories. Our results establish quantum secret sharing as a viable and practically relevant primitive for quantum communication technologies.