Tightly Secure Ring-LWE Based Key Encapsulation with Short Ciphertexts

Martin Albrecht, Emmanuela Orsini, Kenneth Paterson, Guy Peer, Nigel Smart

Research output: Chapter in Book/Report/Conference proceedingConference contribution

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We provide a tight security proof for an IND-CCA Ring-LWE based Key Encapsulation Mechanism that is derived from a generic construction of Dent (IMA Cryptography and Coding, 2003). Such a tight reduction is not known for the generic construction. The resulting scheme has shorter ciphertexts than can be achieved with other generic constructions of Dent or by using the well-known Fujisaki-Okamoto constructions (PKC 1999, Crypto 1999). Our tight security proof is obtained by reducing to the security of the underlying Ring-LWE problem, avoiding an intermediate reduction to a CPA-secure encryption scheme. The proof technique maybe of interest for other schemes based on LWE and Ring-LWE.
Original languageEnglish
Title of host publicationComputer Security – ESORICS 2017
Number of pages18
ISBN (Electronic)978-3-319-66402-6
ISBN (Print)978-3-319-66401-9
Publication statusPublished - 2017

Publication series

NameLecture Notes in Computer Science
PublisherSpringer International Publishing
ISSN (Print)0302-9743

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