54 research outputs found
Johnson(-like)-Noise-Kirchhoff-Loop Based Secure Classical Communicator Characteristics, for Ranges of Two to Two Thousand Kilometers, via Model-Line
A pair of Kirchhoff-Loop-Johnson(-like)-Noise communicators, which is able to
work over variable ranges, was designed and built. Tests have been carried out
on a model-line performance characteristics were obtained for ranges beyond the
ranges of any known direct quantum communication channel and they indicate
unrivalled signal fidelity and security performance of the exchanged raw key
bits. This simple device has single-wire secure key generation and sharing
rates of 0.1, 1, 10, and 100 bit/second for corresponding copper wire
diameters/ranges of 21 mm / 2000 km, 7 mm / 200 km, 2.3 mm / 20 km, and 0.7 mm
/ 2 km, respectively and it performs with 0.02% raw-bit error rate (99.98 %
fidelity). The raw-bit security of this practical system significantly
outperforms raw-bit quantum security. Current injection breaking tests show
zero bit eavesdropping ability without triggering the alarm signal, therefore
no multiple measurements are needed to build an error statistics to detect the
eavesdropping as in quantum communication. Wire resistance based breaking tests
of Bergou-Scheuer-Yariv type give an upper limit of eavesdropped raw bit ratio
of 0.19 % and this limit is inversely proportional to the sixth power of cable
diameter. Hao's breaking method yields zero (below measurement resolution)
eavesdropping information.Comment: Featured in New Scientist, Jason Palmer, May 23, 2007.
http://www.ece.tamu.edu/%7Enoise/news_files/KLJN_New_Scientist.pdf
Corresponding Plenary Talk at the 4th International Symposium on Fluctuation
and Noise, Florence, Italy (May 23, 2007
Enhanced secure key exchange systems based on the Johnson-noise scheme
We introduce seven new versions of the Kirchhoff-Law-Johnson-(like)-Noise
(KLJN) classical physical secure key exchange scheme and a new transient
protocol for practically-perfect security. While these practical improvements
offer progressively enhanced security and/or speed for the non-ideal
conditions, the fundamental physical laws providing the security remain the
same.
In the "intelligent" KLJN (iKLJN) scheme, Alice and Bob utilize the fact that
they exactly know not only their own resistor value but also the stochastic
time function of their own noise, which they generate before feeding it into
the loop.
In the "multiple" KLJN (MKLJN) system, Alice and Bob have publicly known
identical sets of different resistors with a proper, publicly known truth table
about the bit-interpretation of their combination. In the "keyed" KLJN (KKLJN)
system, by using secure communication with a formerly shared key, Alice and Bob
share a proper time-dependent truth table for the bit-interpretation of the
resistor situation for each secure bit exchange step during generating the next
key.
The remaining four KLJN schemes are the combinations of the above protocols
to synergically enhance the security properties. These are: the
"intelligent-multiple" (iMKLJN), the "intelligent-keyed" (iKKLJN), the
"keyed-multiple" (KMKLJN) and the "intelligent-keyed-multiple" (iKMKLJN) KLJN
key exchange systems.
Finally, we introduce a new transient-protocol offering practically-perfect
security without privacy amplification, which is not needed at practical
applications but it is shown for the sake of ongoing discussions.Comment: This version is accepted for publicatio
Effective Privacy Amplification for Secure Classical Communications
We study the practical effectiveness of privacy amplification for classical
key-distribution schemes. We find that in contrast to quantum key distribution
schemes, the high fidelity of the raw key generated in classical systems allow
the users to always sift a secure shorter key if they have an upper bound on
the eavesdropper probability to correctly guess the exchanged key-bits. The
number of privacy amplification iterations needed to achieve information leak
of 10^-8 in existing classical communicators is 2 or 3 resulting in a
corresponding slowdown 4 to 8. We analyze the inherent tradeoff between the
number of iterations and the security of the raw key. This property which is
unique to classical key distribution systems render them highly useful for
practical, especially for noisy channels where sufficiently low quantum bit
error ratios are difficult to achieve.Comment: 11 pages, 3 figure
Totally secure classical networks with multipoint telecloning (teleportation) of classical bits through loops with Johnson-like noise
First, we show a new inexpensive defense against intruders and the
man-in-the-middle attack in the Kirchhoff's-loop-Johnson-like-noise (KLJN)
cipher. Then instead of point-to-point communication, we propose a high
efficiency, secure network. The (in the idealistic case totally secure)
classical network is based on an improved version of the KLJN cipher. The
network consists of two parallel networks: i) a chain-like network of securely
communicating, electrically isolated Kirchhoff-loops with Johnson-like noise
and driven by a specific switching process of the resistances; ii) and a
regular non-secure data network with a Coordinator-server. If the classical
network is fast enough, the chain-like network of N communicators can generate
and share an N bit long secret key within a single clock period of the ciphers
and that implies a significant speed-up compared to the point-to-point key
exchanges used by quantum communication or RSA-like key exchange methods. This
is a teleportation-type multiple telecloning of the classical information bit
because the information transfer can take place without the actual presence of
the information bit at the intermediate points of the network. With similar
quantum schemes the telecloning of classical bits via quantum communicator
networks without telecloning the quantum states is also possible.Comment: Quantum-based network application added. 13 page
Noise properties in the ideal Kirchhoff-Law-Johnson-Noise secure communication system
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
On KLJN-based secure key distribution in vehicular communication networks
In a former paper [Fluct. Noise Lett., 13 (2014) 1450020] we introduced a
vehicular communication system with unconditionally secure key exchange based
on the Kirchhoff-Law-Johnson-Noise (KLJN) key distribution scheme. In this
paper, we address the secure KLJN key donation to vehicles. This KLJN key
donation solution is performed lane-by-lane by using roadside key provider
equipment embedded in the pavement. A method to compute the lifetime of the
KLJN key is also given. This key lifetime depends on the car density and gives
an upper limit of the lifetime of the KLJN key for vehicular communication
networks.Comment: Accepted for publicatio
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