Cuong Le Quoc

Towards the world-wide quantum network

By Cuong Le Quoc, Patrick Bellot, Akim Demaille

2008-01-25

In Proceedings of the 4th information security practice and experience conference (ISPEC’08)

Abstract

Quantum Key Distribution (QKD) networks are of much interest due to their capacity of providing extremely high security keys to network participants. Most QKD network studies so far focus on trusted models where all the network nodes are assumed to be perfectly secured. This restricts QKD networks to be small. In this paper, we first develop a novel model dedicated to large-scale QKD networks, some of whose nodes could be eavesdropped secretly. Then, we investigate the key transmission problem in the new model by an approach based on percolation theory and stochastic routing. Analyses show that under computable conditions large-scale QKD networks could protect secret keys with an extremely high probability. Simulations validate our results.

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On the security of quantum networks: A proposal framework and its capacity

By Cuong Le Quoc, Patrick Bellot, Akim Demaille

2007-03-10

In Proceedings of the 2007 international conference on new technologies, mobility and security (NTMS’07)

Abstract

In large Quantum Key Distribution (QKD)-based networks, intermediate nodes are necessary because of the short length of QKD links. They have tendency to be used more than classical networks. A realistic assumption is that there are eavesdropping operations in these nodes without knowledge of legitimate network participants. We develop a QKD-based network framework. We present a percolation-based approach to discuss about conditions of extremely high secret key transmission. We propose also an adaptive stochastic routing algorithm that helps on protecting keys from reasonable eavesdroppers in a dense QKD network. We show that under some assumptions, one could prevent eavesdroppers from sniffing the secrets with an arbitrarily large probability.

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Stochastic routing in large grid-shaped quantum networks

By Cuong Le Quoc, Patrick Bellot, Akim Demaille

2006-12-04

In Proceedings of the fifth international conference on computer sciences, research, innovation and vision for the future (RIVF’07)

Abstract

This paper investigates the problem of secret key transmissions for an arbitrary Alice-Bob pair in Quantum Key Distribution-based networks. We develop a realistic QKD-based network framework and we show that the key transmission problem on such a framework can be considered as a variant of the classical percolation problem. We also present an adaptive stochastic routing algorithm protect from inevitable eavesdroppers. Simulations were carried out not only to validate our approach, but also to compute critical parameters ensuring security. These results show that large quantum networks with eavesdroppers do provide security.

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