18 research outputs found
Bird's-eye view on Noise-Based Logic
Noise-based logic is a practically deterministic logic scheme inspired by the
randomness of neural spikes and uses a system of uncorrelated stochastic
processes and their superposition to represent the logic state. We briefly
discuss various questions such as (i) What does practical determinism mean?
(ii) Is noise-based logic a Turing machine? (iii) Is there hope to beat (the
dreams of) quantum computation by a classical physical noise-based processor,
and what are the minimum hardware requirements for that? Finally, (iv) we
address the problem of random number generators and show that the common belief
that quantum number generators are superior to classical (thermal) noise-based
generators is nothing but a myth.Comment: paper in pres
On the "cracking" scheme in the paper "A directional coupler attack against the Kish key distribution system" by Gunn, Allison and Abbott
Recently, Gunn, Allison and Abbott (GAA)
[http://arxiv.org/pdf/1402.2709v2.pdf] proposed a new scheme to utilize
electromagnetic waves for eavesdropping on the Kirchhoff-law-Johnson-noise
(KLJN) secure key distribution. We proved in a former paper [Fluct. Noise Lett.
13 (2014) 1450016] that GAA's mathematical model is unphysical. Here we analyze
GAA's cracking scheme and show that, in the case of a loss-free cable, it
provides less eavesdropping information than in the earlier
(Bergou)-Scheuer-Yariv mean-square-based attack [Kish LB, Scheuer J, Phys.
Lett. A 374 (2010) 2140-2142], while it offers no information in the case of a
lossy cable. We also investigate GAA's claim to be experimentally capable of
distinguishing - using statistics over a few correlation times only - the
distributions of two Gaussian noises with a relative variance difference of
less than 10^-8. Normally such distinctions would require hundreds of millions
of correlations times to be observable. We identify several potential
experimental artifacts as results of poor KLJN design, which can lead to GAA's
assertions: deterministic currents due to spurious harmonic components caused
by ground loops, DC offset, aliasing, non-Gaussian features including
non-linearities and other non-idealities in generators, and the time-derivative
nature of GAA's scheme which tends to enhance all of these artifacts.Comment: This version is accepted for publication in Metrology and Measurement
System