Related papers: Is Quantum Bit Commitment Really Possible?

We consider quantum key distribution implementations in which the receiver's apparatus is fixed and does not depend on his choice of basis at each qubit transmission. We show that, although theoretical quantum key distribution is proven…

We note that the proof of the no-go theorem of unconditionally secure quantum bit commitment is based on a model which is not universal. For protocols not described by the model, this theorem does not apply. Using unstable particles and a…

So-called non-local boxes, which have been introduced as an idealization-in different respects-of the behavior of entangled quantum states, have been known to allow for unconditional bit commitment between the two involved parties. We show…

We present protocols for quantum key distribution in a prepare-and-measure setup with an asymmetric level of trust. While the device of the sender (Alice) is partially characterized, the receiver's (Bob's) device is treated as a black-box.…

A broadcasting multiple blind signature scheme based on quantum GHZ entanglement has been presented recently by Tian et al. It is said that the scheme's unconditional security is guaranteed by adopting quantum key preparation, quantum…

Public-key cryptosystems for quantum messages are considered from two aspects: public-key encryption and public-key authentication. Firstly, we propose a general construction of quantum public-key encryption scheme, and then construct an…

We give a (remote) quantum gambling scheme that makes use of the fact that quantum nonorthogonal states cannot be distinguished with certainty. In the proposed scheme, two participants Alice and Bob can be regarded as playing a game of…

We reconsider the concept of multi-prover commitments, as introduced in the late eighties in the seminal work by Ben-Or et al. As was recently shown by Cr\'{e}peau et al., the security of known two-prover commitment schemes not only relies…

We study cheating strategies against a practical four-state quantum bit-commitment protocol and its two-state variant when the underlying quantum channels are noisy and the cheating party is constrained to using single-qubit measurements…

A quantum key distribution protocol based on quantum encryption is presented in this Brief Report. In this protocol, the previously shared Einstein-Podolsky-Rosen pairs act as the quantum key to encode and decode the classical cryptography…

We present a quantum secure direct communication scheme achieved by swapping quantum entanglement. In this scheme a set of ordered Einstein-Podolsky-Rosen (EPR) pairs is used as a quantum information channel for sending secret messages…

Secure key distribution among two remote parties is impossible when both are classical, unless some unproven (and arguably unrealistic) computation-complexity assumptions are made, such as the difficulty of factorizing large numbers. On the…

Unconditionally secure quantum bit commitment (QBC) was widely believed to be impossible for more than two decades. But recently, based on an anomalous behavior found in quantum steering, we proposed a QBC protocol which can be…

Oblivious transfer is the cryptographic primitive where Alice sends one of two bits to Bob but is oblivious to the bit received. Using quantum communication, we can build oblivious transfer protocols with security provably better than any…

Most of the quantum secure direct communication protocol needs a pre-established secure quantum channel. Only after insuring the security of quantum channel, could the sender encode the secret message and send them to the receiver through…

As a new model for signing quantum message, arbitrated quantum signature (AQS) has recently received a lot of attention. In this paper we study the cryptanalysis of previous AQS protocols from the aspects of forgery and disavowal. We show…

Coin flipping is a cryptographic primitive in which two distrustful parties wish to generate a random bit in order to choose between two alternatives. This task is impossible to realize when it relies solely on the asynchronous exchange of…

Quantum protocols for coin-flipping can be composed in series in such a way that a cheating party gains no extra advantage from using entanglement between different rounds. This composition principle applies to coin-flipping protocols with…

Mistrustful cryptography includes important tasks like bit commitment, oblivious transfer, coin flipping, secure computations, position authentication, digital signatures and secure unforgeable tokens. Practical quantum implementations…

The security of quantum exam [Phys. Lett. A 350 (2006) 174] is analyzed and it is found that this protocol is secure for any eavesdropper except for the "students" who take part in the exam. Specifically, any student can steal other…