On the security of interferometric quantum key distribution

Ran Gelles, Tal Mor

Research output: Chapter in Book/Report/Conference proceedingConference contributionpeer-review

3 Scopus citations


Photonic quantum key distribution (QKD) is commonly implemented using interferometers, devices that inherently cause the addition of vacuum ancillas, thus enlarging the quantum space in use. This enlargement sometimes exposes the implemented protocol to new kinds of attacks that have not yet been analyzed. We consider several QKD implementations that use interferometers, and analyze the enlargement of the quantum space caused by the interferometers. While we show that some interferometric implementations are robust (against simple attacks), our main finding is that several other implementations used in QKD experiments are totally insecure. This result is somewhat surprising since although we assume ideal devices and an underlying protocol which is proven secure (e.g., the Bennett-Brassard QKD), the realization is insecure. Our novel attack demonstrates the risks of using practical realizations without performing an extensive security analysis of the specific setup in use.

Original languageEnglish
Title of host publicationTheory and Practice of Natural Computing - First International Conference, TPNC 2012, Proceedings
Number of pages14
StatePublished - 2012
Externally publishedYes
Event1st International Conference on the Theory and Practice of Natural Computing, TPNC 2012 - Tarragona, Spain
Duration: 2 Oct 20104 Oct 2010

Publication series

NameLecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)
Volume7505 LNCS
ISSN (Print)0302-9743
ISSN (Electronic)1611-3349


Conference1st International Conference on the Theory and Practice of Natural Computing, TPNC 2012


  • Implementation loopholes
  • Quantum Cryptography
  • Quantum Key Distribution
  • Security


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