Related papers: Security of the Bennett 1992 quantum-key distribut…
We suggest here a two-point eavesdropping strategy to two nonorthogonal states protocol of quantum key distribution over a fiber-optic channel. Suppose that the single-photon sources and detectors of Alice, Bob and Eves are ideal ones, the…
We study eavesdropping in quantum key distribution with the six state protocol,when the signal states are mixed with white noise. This situation may arise either when Alice deliberately adds noise to the signal states before they leave her…
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…
Inspired from quantum key distribution, we consider wireless communication between Alice and Bob when the intermediate space between Alice and Bob is controlled by Eve. That is, our model divides the channel noise into two parts, the noise…
In semiquantum key-distribution (Boyer et al.) Alice has the same capability as in BB84 protocol, but Bob can measure and prepare qubits only in $\{|0\rangle, |1\rangle\}$ basis and reflect any other qubit. We study an eavesdropping…
We show that the security proof of the Bennett 1992 protocol over loss-free channel in (K. Tamaki, M. Koashi, and N. Imoto, Phys. Rev. Lett. 90, 167904 (2003)) can be adapted to accommodate loss. We assumed that Bob's detectors discriminate…
In this paper, we derive key-rate expressions for different quantum key distribution protocols. Our key-rate equations utilize multiple channel statistics, including those gathered from mismatched measurement bases - i.e., when Alice and…
Quantum key distribution (QKD) allows two parties to establish a shared secret key that is secure against all-powerful adversaries. One such protocol named B92 is quite appealing due to its simplicity but is highly sensitive to channel…
In this paper we present finite-key security analysis for quantum key distribution protocol based on weak coherent (in particular phase-coded) states using a fully quantum asymptotic equipartition property technique. This work is the…
In this paper, we propose a method of enciphering quantum states of two-state systems (qubits) for sending them in secrecy without entangled qubits shared by two legitimate users (Alice and Bob). This method has the following two…
We propose a rotationally-invariant quantum key distribution scheme that uses a pair of orthogonal qubit trines, realized as mixed states of three physical qubits. The measurement outcomes do not depend on how Alice and Bob choose their…
Quantum key distribution allows two parties, traditionally known as Alice and Bob, to establish a secure random cryptographic key if, firstly, they have access to a quantum communication channel, and secondly, they can exchange classical…
We investigate the possibility of eavesdropping on a quantum key distribution network by local sequential quantum unsharp measurement attacks by the eavesdropper. In particular, we consider a pure two-qubit state shared between two parties…
We introduce a constructive method to calculate the achievable secret key rate for a generic class of quantum key distribution protocols, when only a finite number n of signals is given. Our approach is applicable to all scenarios in which…
We present and analyze a quantum key distribution protocol based on sending entangled N-qubit states instead of single-qubit ones as in the trail-blazing scheme by Bennett and Brassard (BB84). Since the qubits are sent individually, an…
We propose a two-way secure-communication protocol in which Alice uses an amplified spontaneous emission source while Bob employs binary phase-shift keying and an optical amplifier. Against an eavesdropper who captures all the light lost in…
The ideal Bennett-Brassard 1984 (BB84) quantum key distribution protocol is based on the preparation and measurement of qubits in two alternative bases differing by an angle of pi/2. Any real implementation of the protocol, though, will…
In quantum key distribution, one conservatively assumes that the eavesdropper Eve is restricted only by physical laws, whereas the legitimate parties, namely the sender Alice and receiver Bob, are subject to realistic constraints, such as…
An elementary derivation of best eavesdropping strategies for the 4 state BB84 quantum cryptography protocol is presented, for both incoherent and two--qubit coherent attacks. While coherent attacks do not help Eve to obtain more…
The "semiquantum" key distribution protocol introduced by Zou et al. [Phys. Rev. A Vol.79, 052312 (2009)] is examined. The protocol while using two-way quantum communication requires only Bob to be fully quantum. We derive a trade-off…