2002/12/31 by Geraldo A. Barbosa
Computer Science · Physics and Astronomy · #Quantum Information and Cryptography #Quantum Mechanics and Applications #Quantum optics and atomic interactions #quant-ph
paper · pdf · doi:10.1103/physreva.68.052307
published as G. A. Barbosa, PRA 68, 052307 (2003) · 11 pages and 4 figures. This version updates the one published in PRA 68, 052307 (2003). Minor changes were made in the text and one section on Mutual Information was added
openalex publication_date 2003/11/04 · arxiv created 2004/04/28 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
This work shows how two parties A and B can securely share unlimited sequences of random bits at optical speeds. A and B possess true-random physical sources and exchange random bits by using a random sequence received to cipher the following one to be sent. A starting shared secret key is used and the method can be described as a one-time-pad unlimited extender. It is demonstrated that the minimum probability of error in signal determination by the eavesdropper can be set arbitrarily close to the pure guessing level. Being based on the M-ry encryption protocol this method also allows for optical amplification without security degradation, offering practical advantages over the Bennett-Brassard 1984 protocol for key distribution.