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Related papers: Estimates for practical quantum cryptography

200 papers

We present an approach to the unconditional security of quantum key distribution protocols based on the uncertainty principle. The approach applies to every case that has been treated via the argument by Shor and Preskill, and relieve them…

Quantum Physics · Physics 2007-05-23 Masato Koashi

Cryptographic key exchange protocols traditionally rely on computational conjectures such as the hardness of prime factorisation to provide security against eavesdropping attacks. Remarkably, quantum key distribution protocols like the one…

The Bennett-Brassard 1984 protocol (BB84 protocol) is one of the simplest protocols for implementing quantum key distribution (QKD). In the protocol, the sender and the receiver iteratively choose one of two complementary measurement bases.…

Quantum Physics · Physics 2025-12-01 Shun Kawakami , Atsushi Taniguchi , Yoshihide Tonomura , Koichi Takasugi , Koji Azuma

We propose an information-theoretically secure encryption scheme for classical messages with quantum ciphertexts that offers detection of eavesdropping attacks, and re-usability of the key in case no eavesdropping took place: the entire key…

Quantum Physics · Physics 2017-05-22 Serge Fehr , Louis Salvail

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…

Quantum Physics · Physics 2008-10-07 Olli Ahonen , Mikko Mottonen , Jeremy L. O'Brien

We propose the use of intra-particle entanglement to enhance the security of a practical implementation of the Bennett-Brassard-1984 (BB84) quantum key distribution scheme. Intra-particle entanglement is an attractive resource since it can…

Quantum Physics · Physics 2013-04-24 S. Adhikari , Dipankar Home , A. S. Majumdar , A. K. Pan , Akshata Shenoy H. , R. Srikanth

Security of the Ekert protocol is proven against individual attacks where an eavesdropper is allowed to share any density matrix with the two communicating parties. The density matrix spans all of the photon number states of both receivers,…

Quantum Physics · Physics 2013-05-29 Edo Waks , Assaf Zeevi , Yoshihisa Yamamoto

This study proposes a quantum secret authentication code for protecting the integrity of secret quantum states. Since BB84[1] was first proposed, the eavesdropper detection strategy in almost all quantum cryptographic protocols is based on…

Quantum Physics · Physics 2011-08-18 Tong-Xuan Wei , Tzonelih Hwang , Chia-Wei Tsai

This paper provides a formula for the sacrifice bit-length for privacy amplification with the Bennett-Brassard 1984 protocol for finite key lengths when we employ the decoy method. Using the formula, we can guarantee the security parameter…

Quantum Physics · Physics 2014-08-26 Masahito Hayashi , Ryota Nakayama

A generalization of the quantum cryptographic protocol by Bennett and Brassard is discussed, using three conjugate bases, i.e. six states. By calculating the optimal mutual information between sender and eavesdropper it is shown that this…

Quantum Physics · Physics 2009-10-31 Dagmar Bruss

We present a protocol for quantum cryptography in which the data obtained for mismatched bases are used in full for the purpose of quantum state tomography. Eavesdropping on the quantum channel is seriously impeded by requiring that the…

Unconditional security proofs of the Bennett-Brassard protocol of quantum key distribution have been obtained recently. These proofs cover also practical implementations that utilize weak coherent pulses in the four signal polarizations.…

Quantum Physics · Physics 2009-11-10 Marcos Curty , Norbert Lütkenhaus

We analyse the finite-size security of the efficient Bennett-Brassard 1984 protocol implemented with decoy states and apply the results to a gigahertz-clocked quantum key distribution system. Despite the enhanced security level, the…

We prove the security of the 1984 protocol of Bennett and Brassard (BB84) for quantum key distribution. We first give a key distribution protocol based on entanglement purification, which can be proven secure using methods from Lo and…

Quantum Physics · Physics 2009-01-23 Peter W. Shor , John Preskill

We consider the Bennett-Brassard cryptographic scheme, which uses two conjugate quantum bases. An eavesdropper who attempts to obtain information on qubits sent in one of the bases causes a disturbance to qubits sent in the other basis. We…

Quantum Physics · Physics 2007-05-23 Christopher A. Fuchs , Nicolas Gisin , Robert B. Griffiths , Chi-Sheng Niu , Asher Peres

A central goal in information theory and cryptography is finding simple characterizations of optimal communication rates subject to various restrictions and security requirements. Ideally, the optimal key rate for a quantum key distribution…

Quantum Physics · Physics 2012-03-28 Graeme Smith , Joseph M. Renes , John A. Smolin

Quantum cryptography uses techniques and ideas from physics and computer science. The combination of these ideas makes the security proofs of quantum cryptography a complicated task. To prove that a quantum-cryptography protocol is secure,…

Quantum Physics · Physics 2015-05-13 Normand J. Beaudry

Security against simple eavesdropping attacks is demonstrated for a recently proposed quantum key distribution protocol which uses the Fibonacci recursion relation to enable high-capacity key generation with entangled photon pairs. No…

Quantum Physics · Physics 2015-04-13 David S. Simon , Casey Fitzpatrick , Alexander V. Sergienko

We prove the security of the Bennett-Brassard (BB84) quantum key distribution protocol in the case where the key information is encoded in the relative phase of a coherent-state reference pulse and a weak coherent-state signal pulse, as in…

Quantum Physics · Physics 2008-02-27 Hoi-Kwong Lo , John Preskill

Quantum cryptography is the study of delivering secret communications across a quantum channel. Recently, Quantum Key Distribution (QKD) has been recognized as the most important breakthrough in quantum cryptography. This process…

Quantum Physics · Physics 2024-01-18 Neha Sharma , Vikas Saxena