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The development of science and technology and communication technology has been widely applied to life, such as unmanned driving, smart home, and smart transportation. Among them, smart home is the closest to people’s life and is welcomed by people. Residents can control home smart devices only through mobile phones, both convenient and fast. However, if users log in and use their smart devices in an insecure way, they are likely to be exposed to all kinds of attacks, leading to the disclosure of private data. Therefore, this paper proposes a verifiable session key agreement protocol for smart home environment based on the parity characteristics after Bell states entanglement swapping, which establishes and negotiates the shared session key between users and smart devices through a public channel. After the session key is established, both parties check the key and finally determine it. Our protocol has high security, which not only verifies the correctness of the session key, but also verifies the authenticity of the user’s identity. In addition, it is feasible to implement the proposed protocol with the existing quantum technology.

In current verifiable quantum state sharing schemes, the dishonest behaviors of certain participants can be verified. However, these schemes have either high resource consumption, low verification efficiency or lack simulation implementations. To compensate for the shortcomings of current schemes, a new verifiable (t, n) threshold quantum state sharing scheme on the IBM quantum cloud platform is proposed. To reduce resource consumption, the proposed scheme prepares only one secret particle and then performs the Lagrange unitary operator on it, and the transformed secret particle is shared in the authorized subset of participants. To improve verification efficiency, the scheme performs the composite rotation unitary operator on the received message particle, such that it not only verifies the validity of the message particle but also reconstructs the original secret particle. The correctness of the proposed scheme is verified by not only mathematic proof but also experimental simulation on the IBM quantum cloud platform. Compared with the two other schemes based on the rotation unitary operator, the proposed scheme provides stronger verification security by using the private shadow key and rotation key. Compared with the two other schemes based on the verification mechanism, the proposed scheme has lower resource consumption and higher verification efficiency.

Quantum secret sharing (QSS) schemes without entanglement have huge advantages in scalability and are easier to realize as they only require sequential communications of a single quantum system. However, these schemes often come with drawbacks such as exact ($n, n$) structure, security flaws and absences of effective cheating detections. To address these problems, we propose a verifiable framework by utilizing entanglement-free states to construct ($t, n$)-QSS schemes. Our work is the heuristic step towards information-theoretical security in entanglement-free QSS, and it sheds light on how to establish effective verification mechanism against cheating. As a result, the proposed framework has a significant importance in constructing QSS schemes for versatile applications in quantum networks due to its intrinsic scalability, flexibility and information theoretical security.

Blind quantum computation (of a single-server case) is a two-party cryptographic protocol which involves a quantum computation server Bob and a client Alice who wants to delegate her quantum computation to Bob without revealing her quantum algorithms and her input to and output from the algorithms. Since Bob may be truant and pretend to execute some computation, Alice wants to verify Bob’s honesty on computation. To resolve this problem, the notion of the verifiability has been considered in the literature and several protocols of verifiable blind computation have been developed. Verifiable blind quantum computation enables Alice to check whether Bob is cheating or not. In addition to the above problem, another problem could arise. If Alice pretends to be a client and is actually a competitor against Bob, then she might slander Bob by fabricating his dishonesty. Therefore, if either Alice or Bob is cheating, then a “neutral” referee other than Alice and Bob should judge which is honest. The standard definition of the verifiability guarantees that only Alice can verify Bob’s computation, and thus, it should be called private verifiability. If Bob claims his innocence though he is actually cheating, then Alice cannot persuade any others that Bob is really cheating while Alice can recognize Bob’s cheating. In this paper, we incorporate arbitrators as the third party into blind quantum computation to resolve the above problems and give an arbitrable blind quantum computation scheme, which provides public verifiability in some sense.

An efficient quantum secret sharing scheme is proposed, in which the dealer generates some single particles and then uses the operations of quantum-controlled-not and Hadamard gate to encode a determinate secret into these particles. The participants get their shadows by performing the single-particle measurements on their particles, and even the dealer cannot know their shadows. Compared to the existing schemes, our scheme is more practical within the present technologies.

After analyzing Yang's verifiable quantum secret sharing (VQSS) scheme, we show that in their scheme a participant can prepare a false quantum particle sequence corresponding to a forged share, while other any participant cannot trace it. In addition, an attacker or a participant can forge a new quantum sequence by transforming an intercepted quantum sequence; moreover, the forged sequence can pass the verification of other participants. So we propose a new VQSS scheme to improve the existed one. In the improved scheme, we construct an identity-based quantum signature encryption algorithm, which ensures chosen plaintext attack security of the shares and their signatures transmitted in the quantum tunnel. We employ dual quantum signature and one-way function to trace against forgery and repudiation of the deceivers (dealer or participants). Furthermore, we add the reconstruction process of quantum secret and prove the security property against superposition attack in this process.

A proactive quantum secret sharing scheme is proposed, in which the participants can update their key shares periodically. In an updating period, one participant randomly generates the EPR pairs, and the other participants update their key shares and perform the corresponding unitary operations on the particles of the EPR pairs. Then, the participant who generated the EPR pairs performs the Bell-state measurement and updates his key share according to the result of the Bell-state measurement. After an updating period, each participant can change his key share, but the secret is changeless, and the old key shares will be useless even if they have been stolen by the attacker. The proactive property of our scheme is very useful to resist the mobile attacker.

This paper proposes a multi-party semi-quantum secret sharing (MSQSS) protocol which allows a quantum party (manager) to share a secret among several classical parties (agents) based on GHZ-like states. By utilizing the special properties of GHZ-like states, the proposed scheme can easily detect outside eavesdropping attacks and has the highest qubit efficiency among the existing MSQSS protocols. Then, we illustrate an efficient way to convert the proposed MSQSS protocol into a multi-party semi-quantum key distribution (MSQKD) protocol. The proposed approach is even useful to convert all the existing measure–resend type of semi-quantum secret sharing protocols into semi-quantum key distribution protocols.

In the paper, Qin and Dai (Quantum Inf Process 14:4237---4244, 2015) proposed a proactive quantum secret sharing scheme. We study the security of the proposed scheme and find that it is not secure. In the distribution phase of the proposed scheme, two dishonest participants may collaborate to eavesdrop the secret of the dealer without introducing any error.

Through generating the d-dimensional GHZ state in the Z-basis and measuring it in the X-basis, a dynamic quantum secret sharing scheme is proposed. In the proposed scheme, multiple participants can be added or deleted in one update period, and the shared secret does not need to be changed. The participants can be added or deleted by themselves, and the dealer does not need to be online. Compared to the existing schemes, the proposed scheme is more efficient and more practical.

This work proposes a new dynamic quantum secret sharing (DQSS) protocol using the measurement property of Greenberger---Horne---Zeilinger state and the controlled-NOT gate. In the proposed DQSS protocol, an agent can obtain a shadow of the secret key by simply performing a measurement on single photons. In comparison with the existing DQSS protocols, it provides better qubit efficiency and has an easy way to add a new agent. The proposed protocol is also free from the eavesdropping attack, the collusion attack, and can have an honesty check on a revoked agent.

Quantum secret sharing (QSS) refers to the process in which the secret is divided into several sub-secrets and sent to different users utilizing quantum technology. Only the user belonging to a specific subset (authorized set) can reconstruct the initial secret correctly. In principle, the authorized set can regain the initial secret exactly via sub-secrets. However, when realizing QSS in practice, because of the interference of various noises, the secret obtained by the authorized set may not be consistent with the initial one. For a particular kind of QSS protocols, in which the bitwise XOR of sub-secrets is equal to the initial secret theoretically, we propose a feasible multiparty error-correcting method based on binary search technique and two-party Cascade error-correcting method. With this method, we can solve the problem that the authorized set cannot regain the initial secret correctly. Finally, we analyze the optimal block length, the amount of leaked information, and realize tripartite error-correcting method by experimental simulation.

Recently, a kind of quantum secret sharing protocol with collective eavesdropping check was proposed by Lin et al. In this paper, we present a one-insider attack against Lin's three-party protocol. With the method of intercept-resending and entanglement-swapping, we show that the insider participant who performs the last local operation on the qubit sent by the secret sender could illegally extract the secret messages without being detected. This greatly improves the two-insider-collaborating attacks proposed by Gao and Liu, respectively. Furthermore, such an attacking method also applies in the $$n$$n-party version of such a secret sharing protocol. Our attack method once more shows the power of intercept-resend attack and poses the importance of information authentication in quantum and classic communications.

Hsu et al. (Quantum Inf Process 12:331---344,2013) proposed a dynamic quantum secret sharing (DQSS) protocol using the entanglement swapping of Bell states for an agent to easily join (or leave) the system. In 2013, Wang and Li (Quantum Inf Process 12(5):1991---1997, 2013) proposed a collusion attack on Hsu et al.'s DQSS protocol. Nevertheless, this study points out a new security issue on Hsu et al.'s DQSS protocol regarding to the honesty of a revoked agent. Without considering this issue, the DQSS protocol could be failed to provide secret sharing function.

Secret sharing plays a fundamental role in both secure multi-party computation and modern cryptography. We present a new quantum secret sharing scheme based on quantum Fourier transform. This scheme enjoys the property that each share of a secret is disguised with true randomness, rather than classical pseudorandomness. Moreover, under the only assumption that a top priority for all participants (secret sharers and recovers) is to obtain the right result, our scheme is able to achieve provable security against a computationally unbounded attacker.

We analyze the security of a dynamic quantum secret sharing scheme. The analysis shows that the first agent and the last one can gain access to the dealer's master key without the others' cooperation by a special participant attack in this scheme.

Recently, a high-dimensional deterministic multiparty quantum secret sharing (DMQSS) scheme was proposed (Liu ZH et al in Quantum Inf Process 1---11 2011). However, we show that the scheme is vulnerable to a specific kind of collusion attack. In the worst case, $${\left\lfloor n/2\right\rfloor+1}$$ agents can collude elaborately to reveal the dealer's secret without the help of the other agents. We present the attack strategy in details and also give two possible improvements to resist the proposed collision attack.

We present a three-party quantum secret sharing (QSS) scheme via the entangled Greenberger---Horne---Zeilinger state. In this scheme, the sender Alice encodes her arbitrary secret information by means of preparing a single-particle quantum state. The agent Bob obtains his shared information according to his hobby, while Charlie can easily calculate his shared information. The proposed scheme is secure. It is shown that even a dishonest agent, who may avoid the security checking, cannot obtain any useful information. Moreover, we further investigate the multi-party QSS scheme which allows most agents to predetermine their information.

Combining the block transmission in Long and Liu (Phys Rev A 65:032302, 2002) and the double operations in Lin et al. (Opt Commun 282:4455, 2009), we propose a secure multiparty quantum secret sharing protocol with the collective eavesdropping-check character. In this protocol, only the boss needs to prepare Bell states and perform Bell state measurements, and all agents only perform local operations, which makes this protocol more feasible with the current technique. Incidentally, we show that the other half of secret messages in Lin et al. protocol (Opt Commun 282:4455, 2009) may also be eavesdropped.

A deterministic multiparty quantum secret sharing scheme is put forward, in which Bell states in high-dimensional Hilbert space are used. Only by preforming High-dimensional Bell measurements, all agents can recover the secret according to the dealer's announcement when collaborating with each other. It shows that unitary operation for encoding deterministic secret is unnecessary in quantum communication. The security of the transmission of the high-dimensional Bell states can be ensured by randomly using one of the two mutually unbiased bases for eavesdropping checking, and thus by which the proposed quantum secret sharing scheme is secure against usual attacks. In addition, the proposed scheme has three advantages: generality, high resource capacity and high security.

In a conventional quantum (k, n) threshold scheme, a trusted party shares a quantum secret with n agents such that any k or more agents can cooperate to recover the original secret, while fewer than k agents obtain no information about the secret. Is the reconstructed quantum secret same with the original one? Or is the dishonest agent willing to provide a true share during the secret reconstruction? In this paper we reexamine the security of quantum (k, n) threshold schemes and show how to construct a verifiable quantum (k, n) threshold scheme by combining a qubit authentication process. The novelty of ours is that it can provide a mechanism for checking whether the reconstructed quantum secret is same with the original one. This mechanism can also attain the goal of checking whether the dishonest agent provides a false quantum share during the secret reconstruction such that the secret quantum state cannot be recovered correctly.

In a conventional quantum (k, n) threshold scheme, a trusted party shares a secret quantum state with n participants such that any k of those participants can cooperate to recover the original secret, while fewer than k participants obtain no information about the secret. In this paper we show how to construct a quantum (k, n) threshold scheme without the assistance of a trusted party, who generates and distributes shares among the participants. Instead, each participant chooses his private state and contributes the same to the determination of the final secret quantum state.