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Information theoretic security by the laws of classical physics (plenary paper)

Róbert Mingesz, Kish, L. B., Zoltán Gingl, Granqvist, C. G., He Wen, Peper, F., Eubank, T., Schmera, G.

Published Jan 1, 2013• 0 citations
OpenAlex

Abstract

It has been shown recently that the use of two pairs of resistors withenhanced Johnson-noise and a Kirchhoff-loop—i.e., a Kirchhoff-Law-Johnson-Noise (KLJN) protocol—for secure key distribution leads to information theoreticsecurity levels superior to those of a quantum key distribution, including a naturalimmunity against a man-in-the-middle attack. This issue is becoming particularlytimely because of the recent full cracks of practical quantum communicators, asshown in numerous peer-reviewed publications. This presentation first brieflysurveys the KLJN system and then discusses related, essential questions such as:what are perfect and imperfect security characteristics of key distribution, and howcan these two types of securities be unconditional (or information theoretical)?Finally the presentation contains a live demonstration.

Related papers

Unconditional Security by the Laws of Classical Physics

Róbert Mingesz, László B. Kish, Zoltán Gingl +5 more

Abstract There is an ongoing debate about the fundamental security of existing quantum key exchange schemes. This debate indicates not only that there is a problem with security but also that the meanings of perfect, imperfect, conditional and unconditional (information theoretic) security in physically secure key exchange schemes are often misunderstood. It has been shown recently that the use of two pairs of resistors with enhanced Johnsonnoise and a Kirchhoff-loop ‒ i.e., a Kirchhoff-Law-Johnson-Noise (KLJN) protocol ‒ for secure key distribution leads to information theoretic security levels superior to those of today’s quantum key distribution. This issue is becoming particularly timely because of the recent full cracks of practical quantum communicators, as shown in numerous peer-reviewed publications. The KLJN system is briefly surveyed here with discussions about the essential questions such as (i) perfect and imperfect security characteristics of the key distribution, and (ii) how these two types of securities can be unconditional (or information theoretical).

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UCODITIOAL SECURITY BY THE LAWS OF CLASSICAL PHY SICS 1

Róbert Mingesz, László B. Kish, Zoltán Gingl +5 more

There is an ongoing debate about the fundamental security of existing quantum key exchange schemes. This debate indi cates not only that there is a problem with security but also that the meanings of perfect, imperfect, conditional and unconditional (information theoretic) security in physically secure key exchange schemes are often misunderstood. It has been shown recently that the use of two pairs of resistors with enhanced Johnsonnoise and a Kirchhoff-loop ‒ i.e ., a Kirchhoff-Law-Johnson-Noise (KLJN) protocol ‒ for secure key distribution leads to information theoretic security levels superior to those of today’s quan tum key distribution. This issue is becoming particularly timely because of the recent full cracks of practical quantum communicators, as shown in numerous peer- reviewed publications. The KLJN system is briefly surveyed here with discussions about the essential questions such as ( i) perfect and imperfect security characteristics of the key distribution, and ( ii ) how these two types of securities can be unconditional (or information theoretical).

•Jan 1, 2013•0 citations

Generalized Kirchhoff-Law-Johnson-Noise (KLJN) secure key exchange system using arbitrary resistors

Gergely Vadai, Róbert Mingesz, Zoltán Gingl

The Kirchhoff-Law-Johnson-Noise (KLJN) secure key exchange system has been introduced as a simple, very low cost and efficient classical physical alternative to quantum key distribution systems. The ideal system uses only a few electronic components-identical resistor pairs, switches and interconnecting wires-in order to guarantee perfectly protected data transmission. We show that a generalized KLJN system can provide unconditional security even if it is used with significantly less limitations. The more universal conditions ease practical realizations considerably and support more robust protection against attacks. Our theoretical results are confirmed by numerical simulations.

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Christiana Chamon, Laszlo B. Kish

A secure key distribution (exchange) scheme is unconditionally secure if it is unbreakable against arbitrary technological improvements of computing power and/or any development of new algorithms. There are only two families of experimentally realized and tested unconditionally secure key distribution technologies: quantum key distribution (QKD), the base of quantum cryptography, which utilizes quantum physical photonic features, and the Kirchhoff-Law–Johnson-Noise (KLJN) system that is based on classical statistical physics (fluctuation–dissipation theorem). The focus topic of this paper is the thermodynamical situation of the KLJN system. In all the original works, the proposed KLJN schemes required thermal equilibrium between the devices of the communicating parties to achieve perfect security. However, Vadai et al., in (Nature) Sci. Rep. 5, 13653 (2015) show a modified scheme, where there is a non-zero thermal noise energy flow between the parties, yet the system seems to resist all the known attack types. We introduce an attack type against their system. The attack utilizes coincidence events between the line current and voltages. We show that there is a non-zero information leak toward the Eavesdropper, even under idealized conditions. As soon as the thermal equilibrium is restored, the system becomes perfectly secure again. In conclusion, perfect unconditional security requires thermal equilibrium.

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Noise Properties in the Ideal Kirchhoff-Law-Johnson-Noise Secure Communication System

Zoltán Gingl, Róbert Mingesz

In this paper we determine the noise properties needed for unconditional security for the ideal Kirchhoff-Law-Johnson-Noise (KLJN) secure key distribution system using simple statistical analysis. It has already been shown using physical laws that resistors and Johnson-like noise sources provide unconditional security. However real implementations use artificial noise generators, therefore it is a question if other kind of noise sources and resistor values could be used as well. We answer this question and in the same time we provide a theoretical basis to analyze real systems as well.

arXiv:1403.7243•PLoS ONE•Apr 22, 2014•45 citations

Security and performance analysis of the Kirchhoff-Law-Johnson-Noise secure key exchange protocol

Róbert Mingesz, Zoltán Gingl, Gergely Vadai

The Kirchhoff-Law-Johnson-(like)-Noise (KLJN) key exchange system is a promising low-cost alternative to the quantum key distribution and is based solely on the laws of classical physics. Although several papers have been published in the field, there is still an ongoing debate about the security of the method. In our paper we will give an overview the most important findings about the security of the KLJN system and show the effects of the non-idealities of the system on the information leak. We will also analyze different methods of proposed cracking the KLJN protocol, including the latest directional coupler attack.

International Conference on Noise and Fluctuations•Jun 1, 2015•2 citations
It has been shown recently that the use of two pairs of resistors withenhanced Johnson-noise and a Kirchhoff-loop—i.e., a Kirchhoff-Law-Johnson-Noise (KLJN) protocol—for secure key distribution leads to information theoreticsecurity levels superior to those of a quantum key distribution, including a naturalimmunity against a man-in-the-middle attack. This issue is becoming particularlytimely because of the recent full cracks of practical quantum communicators, asshown in numerous peer-reviewed publications. This presentation first brieflysurveys the KLJN system and then discusses related, essential questions such as:what are perfect and imperfect security characteristics of key distribution, and howcan these two types of securities be unconditional (or information theoretical)?Finally the presentation contains a live demonstration.
Abstract There is an ongoing debate about the fundamental security of existing quantum key exchange schemes. This debate indicates not only that there is a problem with security but also that the meanings of perfect, imperfect, conditional and unconditional (information theoretic) security in physically secure key exchange schemes are often misunderstood. It has been shown recently that the use of two pairs of resistors with enhanced Johnsonnoise and a Kirchhoff-loop ‒ i.e., a Kirchhoff-Law-Johnson-Noise (KLJN) protocol ‒ for secure key distribution leads to information theoretic security levels superior to those of today’s quantum key distribution. This issue is becoming particularly timely because of the recent full cracks of practical quantum communicators, as shown in numerous peer-reviewed publications. The KLJN system is briefly surveyed here with discussions about the essential questions such as (i) perfect and imperfect security characteristics of the key distribution, and (ii) how these two types of securities can be unconditional (or information theoretical).
There is an ongoing debate about the fundamental security of existing quantum key exchange schemes. This debate indi cates not only that there is a problem with security but also that the meanings of perfect, imperfect, conditional and unconditional (information theoretic) security in physically secure key exchange schemes are often misunderstood. It has been shown recently that the use of two pairs of resistors with enhanced Johnsonnoise and a Kirchhoff-loop ‒ i.e ., a Kirchhoff-Law-Johnson-Noise (KLJN) protocol ‒ for secure key distribution leads to information theoretic security levels superior to those of today’s quan tum key distribution. This issue is becoming particularly timely because of the recent full cracks of practical quantum communicators, as shown in numerous peer- reviewed publications. The KLJN system is briefly surveyed here with discussions about the essential questions such as ( i) perfect and imperfect security characteristics of the key distribution, and ( ii ) how these two types of securities can be unconditional (or information theoretical).
The Kirchhoff-Law-Johnson-Noise (KLJN) secure key exchange system has been introduced as a simple, very low cost and efficient classical physical alternative to quantum key distribution systems. The ideal system uses only a few electronic components-identical resistor pairs, switches and interconnecting wires-in order to guarantee perfectly protected data transmission. We show that a generalized KLJN system can provide unconditional security even if it is used with significantly less limitations. The more universal conditions ease practical realizations considerably and support more robust protection against attacks. Our theoretical results are confirmed by numerical simulations.
A secure key distribution (exchange) scheme is unconditionally secure if it is unbreakable against arbitrary technological improvements of computing power and/or any development of new algorithms. There are only two families of experimentally realized and tested unconditionally secure key distribution technologies: quantum key distribution (QKD), the base of quantum cryptography, which utilizes quantum physical photonic features, and the Kirchhoff-Law–Johnson-Noise (KLJN) system that is based on classical statistical physics (fluctuation–dissipation theorem). The focus topic of this paper is the thermodynamical situation of the KLJN system. In all the original works, the proposed KLJN schemes required thermal equilibrium between the devices of the communicating parties to achieve perfect security. However, Vadai et al., in (Nature) Sci. Rep. 5, 13653 (2015) show a modified scheme, where there is a non-zero thermal noise energy flow between the parties, yet the system seems to resist all the known attack types. We introduce an attack type against their system. The attack utilizes coincidence events between the line current and voltages. We show that there is a non-zero information leak toward the Eavesdropper, even under idealized conditions. As soon as the thermal equilibrium is restored, the system becomes perfectly secure again. In conclusion, perfect unconditional security requires thermal equilibrium.
In this paper we determine the noise properties needed for unconditional security for the ideal Kirchhoff-Law-Johnson-Noise (KLJN) secure key distribution system using simple statistical analysis. It has already been shown using physical laws that resistors and Johnson-like noise sources provide unconditional security. However real implementations use artificial noise generators, therefore it is a question if other kind of noise sources and resistor values could be used as well. We answer this question and in the same time we provide a theoretical basis to analyze real systems as well.
The Kirchhoff-Law-Johnson-(like)-Noise (KLJN) key exchange system is a promising low-cost alternative to the quantum key distribution and is based solely on the laws of classical physics. Although several papers have been published in the field, there is still an ongoing debate about the security of the method. In our paper we will give an overview the most important findings about the security of the KLJN system and show the effects of the non-idealities of the system on the information leak. We will also analyze different methods of proposed cracking the KLJN protocol, including the latest directional coupler attack.