@ARTICLE{Chen_Hsien-Pu_On_2014, author={Chen, Hsien-Pu and Kish, Laszlo B. and Granqvist, Claes G.}, number={No 3}, journal={Metrology and Measurement Systems}, pages={389-400}, howpublished={online}, year={2014}, publisher={Polish Academy of Sciences Committee on Metrology and Scientific Instrumentation}, abstract={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 374:2140-2142 (2010)], 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 timederivative nature of GAA’s scheme which tends to enhance all of these artifacts.}, type={Artykuły / Articles}, title={On the “Cracking” Scheme in the Paper “A Directional Coupler Attack Against the Kish Key Distribution System” by Gunn, Allison and Abbott}, URL={http://journals.pan.pl/Content/90254/PDF/Journal10178-VolumeXXI%20Issue3_02.pdf}, doi={10.2478/mms-2014-0033}, keywords={KLJN key exchange, information theoretic security, unconditional security}, }