A power distribution of optical signals as the ciphertext of Y-00 quantum stream cipher transceivers should be uniform, even when the bit sequence of plaintext is a non-uniform sequence. For examining the uniformity, we experimentally measure powers of optical signals with 4096 intensity levels and calculate the ratio of signal numbers over and under the average power. The ratios for various kinds of bit sequences are 0.5 with measurement error of 1%, which is an evidence of the uniformity of the power distribution. In addition, the effectiveness of a randomization technique of overlapping selection keying for enhancing the security against the known plaintext attack is experimentally observed.

Date Published: 30 August 2017
PDF: 9 pages
Proc. SPIE 10409, Quantum Communications and Quantum Imaging XV, 104090I (30 August 2017); doi: 10.1117/12.2273462

Published in SPIE Proceedings Vol. 10409:
Quantum Communications and Quantum Imaging XV
Ronald E. Meyers; Yanhua Shih; Keith S. Deacon, Editor(s)