Related papers: Threshold Quantum Cryptography
We review the implementation of two QKD protocols (BB84 and B92) keeping in mind that their implementations do not easily satisfy the requirement of use of single photons. We argue that current models do not take into account issues raised…
Granting information privacy is of crucial importance in our society, notably in fiber communication networks. Quantum cryptography provides a unique means to establish, at remote locations, identical strings of genuine random bits, with a…
We present a novel one-way quantum key distribution protocol based on 3-dimensional quantum state, a qutrit, that encodes two qubits in its 2-dimensional subspaces. The qubits hold the classical bit information that has to be shared between…
Advances in quantum computing make Shor's algorithm for factorising numbers ever more tractable. This threatens the security of any cryptographic system which often relies on the difficulty of factorisation. It also threatens methods based…
We study position-based cryptography in the quantum setting. We examine a class of protocols that only require the communication of a single qubit and 2n bits of classical information. To this end, we define a new model of communication…
A photon source based on postselection from entangled photon pairs produced by parametric frequency down-conversion is suggested. Its ability to provide good approximations of single-photon states is examined. Application of this source in…
We investigate the post-quantum security of the encrypted key exchange(EKE) protocols based on some basic physical parameters of ion-trap quantum computer, and show that the EKE protocol with a 40-bit password will be secure against a…
We review the current status of security proofs for practical decoy-state Quantum Key Distribution using the BB84 protocol, focusing on optical implementations with weak coherent pulses and threshold photodetectors. The primary aim of this…
Cloud computing has made storing and accessing data easier but keeping it secure is a big challenge nowadays. Traditional methods of ensuring data may not be strong enough in the future when powerful quantum computers become available. To…
We develop an improvement to the weak laser pulse BB84 scheme for quantum key distribution, which utilizes entanglement to improve the security of the scheme and enhance its resilience to the photon-number-splitting attack. This protocol…
We introduce the concept of a superlinear threshold detector, a detector that has a higher probability to detect multiple photons if it receives them simultaneously rather than at separate times. Highly superlinear threshold detectors in…
We describe and experimentally demonstrate a three-party quantum secret sharing protocol using polarization-entangled photon pairs. The source itself serves as an active participant and can switch between the required photon states by…
Quantum key distribution (QKD) protocols are cryptographic techniques with security based only on the laws of quantum mechanics. Two prominent QKD schemes are the BB84 and B92 protocols that use four and two quantum states, respectively. In…
Quantum cryptography has attracted much recent attention due to its potential for providing secret communications that cannot be decrypted by any amount of computational effort. This is the first analysis of the secrecy of a practical…
We consider the problem of secure identification: user U proves to server S that he knows an agreed (possibly low-entropy) password w, while giving away as little information on w as possible, namely the adversary can exclude at most one…
We propose a cryptographic scheme that is deterministic: Alice sends single photons to Bob, and each and every photon detected supplies one key bit -- no photon is wasted. This is in marked contrast to other schemes in which a random…
The quantum key distribution protocol BB84, published by C. H. Bennett and G. Brassard in 1984, describes how two spatially separated parties can generate a random bit string fully known only to them by transmission of single-qubit quantum…
In this Paper, we investigate the security of Zhang, Li and Guo quantum key distribution via quantum encryption protocol [$\text{Phys. Rev. A} \textbf{64}, 24302 (2001)$] and show that it is not secure against some of Eve's attacks and with…
Methods of quantum mechanics promise information-theoretic security for various protocols in cryptography. However, impossibility of some cryptographic applications such as standard bit commitment, oblivious transfer, multiparty secure…
We propose in this paper a novel deterministic protocol using particular maximally entangled states of polarized photons for a genuine bidirectional secure communication setup. We further propose a plausible experimental setup for such a…