Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE

Secure communications using quantum cryptography

Richard Hughes, W. T. Buttler, Paul G. Kwiat, G. G. Luther, George L. Morgan, J. E. Nordholt, Charles G. Peterson, Charles M. Simmons

Published Jul 1, 1997• 24 citations

Publisher

Abstract

The secure distribution of the secret random bit sequences known as `key' material, is an essential precursor to their use for the encryption and decryption of confidential communications. Quantum cryptography is an emerging technology for secure key distribution with single-photon transmissions: Heisenburg's uncertainty principle ensures that an adversary can neither successfully tap the key transmissions, nor evade detection (eavesdropping raises the key error rate above a threshold value). We have developed experimental quantum cryptography systems based on the transmission of non-orthogonal single-photon states to generate shared key material over multi-kilometer optical fiber paths and over line-of-sight links. In both cases, key material is built up using the transmission of a single- photon per bit of an initial secret random sequence. A quantum-mechanically random subset of this sequence is identified, becoming the key material after a data reconciliation stage with the sender. In our optical fiber experiment we have performed quantum key distribution over 24-km of underground optical fiber using single-photon interference states, demonstrating that secure, real-time key generation over `open' multi-km node-to-node optical fiber communications links is possible.

DOI: 10.1117/12.277644

Related papers

Secure Communications Using Quantum Cryptography

Richard Hughes, Buttler, William T., Kwiat, Paul G. +5 more

The secure distribution of the secret random bit sequences known as {open_quotes}key{close_quotes} material, is an essential precursor to their use for the encryption and decryption of confidential communications. Quantum cryptography is an emerging technology for secure key distribution with single-photon transmissions, nor evade detection (eavesdropping raises the key error rate above a threshold value). We have developed experimental quantum cryptography systems based on the transmission of non-orthogonal single-photon states to generate shared key material over multi-kilometer optical fiber paths and over line-of-sight links. In both cases, key material is built up using the transmission of a single-photon per bit of an initial secret random sequence. A quantum-mechanically random subset of this sequence is identified, becoming the key material after a data reconciliation stage with the sender. In our optical fiber experiment we have performed quantum key distribution over 24-km of underground optical fiber using single-photon interference states, demonstrating that secure, real-time key generation over {open_quotes}open{close_quotes} multi-km node-to-node optical fiber communications links is possible. We have also constructed a quantum key distribution system for free-space, line-of-sight transmission using single-photon polarization states, which is currently undergoing laboratory testing. 7 figs.

Jan 1, 19972 citations

Quantum cryptography for secure free-space communications

Richard J. Hughes, William T. Buttler, Paul G. Kwiat +5 more

The secure distribution of the secret random bit sequences known as 'key' material, is an essential precursor to their use for the encryption and decryption of confidential communications. Quantum cryptography is a new technique for secure key distribution with single-photon transmissions: Heisenberg's uncertainty principle ensures that an adversary can neither successfully tap the key transmissions, nor evade detection (eavesdropping raises the key error rate above a threshold value). We have developed experimental quantum cryptography systems based on the transmission of non- orthogonal photon polarization states to generate shared key material over line-of-sight optical links. Key material is built up using the transmission of a single-photon per bit of an initial secret random sequence. A quantum-mechanically random subset of this sequence is identified, becoming the key material after a data reconciliation stage with the sender. We have developed and tested a free-space quantum key distribution (QKD) system over an outdoor optical path of approximately 1 km at Los Alamos National Laboratory under nighttime conditions. Results show that free-space QKD can provide secure real-time key distribution between parties who have a need to communicate secretly. Finally, we examine the feasibility of surface to satellite QKD.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIEApr 26, 199910 citations

Quantum key distribution over a 48 km optical fibre network

Richard Hughes, George L. Morgan, Charles G. Peterson

The secure distribution of the secret random bit sequences known as ‘key’ material, is an essential precursor to their use for the encryption and decryption of confidential communications. Quantum cryptography is a new technique for secure key distribution with single-photon transmissions: Heisenberg's uncertainty principle ensures that an adversary can neither successfully tap the key transmissions, nor evade detection (eavesdropping raises the key error rate above a threshold value). We have developed experimental quantum cryptography systems based on the transmission of non-orthogonal photon states to generate shared key material over multikilometre optical fibre paths and over line-of-sight links. In both cases, key material is built up using the transmission of a single-photon per bit of an initial secret random sequence. A quantum-mechanically random subset of this sequence is identified, becoming the key material after a data reconciliation stage with the sender. Here we report the most recent results of our optical fibre experiment in which we have performed quantum key distribution over a 48 km optical fibre network at Los Alamos using photon interference states with the B92 and BB84 quantum key distribution protocols.

arXiv:quant-ph/9904038Journal of Modern OpticsFeb 1, 2000188 citations

Practical quantum cryptography for secure free-space communications

Richard Hughes, W. T. Buttler, Paul G. Kwiat +4 more

Quantum cryptography is an emerging technology in which two parties may simultaneously generate shared, secret cryptographic key material using the transmission of quantum states of light. The security of these transmissions is based on the inviolability of the laws of quantum mechanics and information-theoretically secure post-processing methods. An adversary can neither successfully tap the quantum transmissions, nor evade detection, owing to Heisenberg's uncertainty principle. In this paper we describe the theory of quantum cryptography, and the most recent results from our experimental free-space system with which we have demonstrated for the first time the feasibility of quantum key generation over a point-to-point outdoor atmospheric path in daylight. We achieved a transmission distance of 0.5 km, which was limited only by the length of the test range. Our results provide strong evidence that cryptographic key material could be generated on demand between a ground station and a satellite (or between two satellites), allowing a satellite to be securely re-keyed on orbit. We present a feasibility analysis of surface-to-satellite quantum key generation.

arXiv:quant-ph/9905009May 4, 199920 citations

Quantum cryptography for secure satellite communications

Richard Hughes, W. T. Buttler, Paul G. Kwiat +4 more

Quantum cryptography is an emerging technology in which two parties may simultaneously generate shared, secret cryptographic key material using the transmission of quantum states of light. The security of these transmissions is based on the inviolability of the laws of quantum mechanics and information-theoretically secure post-processing methods. An adversary can neither successfully tap the quantum transmissions, nor evade detection, owing to Heisenberg's uncertainty principle. In this paper we describe the theory of quantum cryptography, and recent results from our experimental free-space system with which we have demonstrated the feasibility of quantum key generation over a point-to-point outdoor atmospheric path in daylight. We achieved a transmission distance of 0.5 km, which was limited only by the length of the test range. Our results provide strong evidence that cryptographic key material could be generated on demand between a ground station and a satellite (or between two satellites), allowing a satellite to be securely re-keyed on orbit for encrypting the uplinked command path and downlinked data path; or to distribute keys between widely-separated ground stations with a satellite relay, enabling encrypted communications over even inter-continental distances. We present a feasibility analysis of surface-to-satellite quantum key generation.

IEEE Aerospace Conference (AERO)Nov 7, 200237 citations

Practical quantum cryptography for secure free-space communications

Mr. A. Salai Jeyaseelan, Ms.S. Mohana Priya

Quantum Cryptography is an emerging technology in which two parties may simultaneously generate shared, secret cryptographic key material using the transmission of quantum states of light. The security of these transmissions is based on the inviolability of the laws of quantum mechanics and information – theoretically secure post- processing methods. An adversary can neither successfully tap the quantum transmissions, nor evade detection, owing to Heisenberg’s uncertainty principle. In this paper we describe the theory of quantum cryptography and the most recent results from our experimental free space system with which we have demonstrated for the first time the feasibility of quantum key generation over a point-to-point outdoor atmospheric path in daylight. We achieved a transmission distance of 0.5km which was limited only by the length of the test range. Our results provide strong evidence that cryptographic key material could be generated on the demand between a ground station and a satellite (or between two satellites), allowing a satellite to be securely re-keyed on orbit. We present a feasibility analysis of surface-to-satellite quantum key generation.

International Journal of Computer and Communication TechnologyJul 1, 20102 citations