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Václav Matyáš
Secrecy amplification in partially compromised networks
On 2015-03-26 16:00 at KN:E-107
Distribution of cryptographic keys is a cornerstone to most ICT security
solutions. Usage of various key (pre-)distribution schemes in networks with an
active attacker results in a partially compromised network where some fraction
of keys used to protect link communication is known to the attacker. The secrecy
amplification protocols were proposed to secure again some previously
compromised communication links by using non-compromised paths to deliver new
secure keys. Design of suitable secrecy amplification protocols remains a
challenge in scenarios where a trade-off between necessary resources (e.g.,
energy necessary for transmission of message) and improvement in the number of
secure links must be balanced.

This talk will inspect most promising classes of secrecy amplification
protocols. We combine analysis of given protocol participant placement via a
simulator and manual post-processing to provide a simpler, practically usable
hybrid protocol with less steps and lower communication overhead, yet still
better in terms of re-secured links than previously proposed protocols. The talk
is based on results published as: A New Approach to Secrecy Amplification in
Partially Compromised Networks. R Ošťádal, P Švenda, V Matyáš. Security,
Privacy, and Applied Cryptography Engineering (SPACE) 2014. Springer LNCS 8804,
pp. 92-109.
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