Open AccessExplicit attacks on passive side channels of the light source in the BB84 decoy state protocol
Author(s) -
D. V. Babukhin,
Denis Sych
Publication year - 2021
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/1984/1/012008
Subject(s) - quantum key distribution , bb84 , eavesdropping , computer science , protocol (science) , computer security , key (lock) , quantum cryptography , computer network , quantum , physics , quantum information , quantum mechanics , medicine , alternative medicine , pathology
Various imperfections of the hardware in quantum key distribution (QKD) lead to discrepancies between the theory and real-world devices. An eavesdropper can use these discrepancies to compromise the QKD security, thus legitimate sides need to estimate the influence of imperfections to prevent the loss of security. Here we investigate explicit eavesdropping attacks on passive side channels of the light source for a BB84 decoy states QKD protocol. We consider an optimal phase-covariant cloning attack, followed by unambiguous state discrimination and a joint measurement. Our calculations provide a hint that for state-of-the-art light sources the inherent presence of passive side channels still allows the protocol to be secure, albeit with the reduced secret key rates.