Fully Adaptive Decentralized Multi-Authority ABE

Pratish Datta*, Ilan Komargodski, Brent Waters

*Corresponding author for this work

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

4 Scopus citations

Abstract

Decentralized multi-authority attribute-based encryption (MA- ABE ) is a distributed generalization of standard (ciphertext-policy) attribute-based encryption where there is no trusted central authority: any party can become an authority and issue private keys, and there is no requirement for any global coordination other than the creation of an initial set of common reference parameters. We present the first multi-authority attribute-based encryption schemes that are provably fully-adaptively secure. Namely, our construction is secure against an attacker that may corrupt some of the authorities as well as perform key queries adaptively throughout the life-time of the system. Our main construction relies on a prime order bilinear group where the k-linear assumption holds as well as on a random oracle. Along the way, we present a conceptually simpler construction relying on a composite order bilinear group with standard subgroup decision assumptions as well as on a random oracle. Prior to this work, there was no construction that could resist adaptive corruptions of authorities, no matter the assumptions used. In fact, we point out that even standard complexity leveraging style arguments do not work in the multi-authority setting.

Original languageAmerican English
Title of host publicationAdvances in Cryptology – EUROCRYPT 2023 - 42nd Annual International Conference on the Theory and Applications of Cryptographic Techniques, 2023, Proceedings
EditorsCarmit Hazay, Martijn Stam
PublisherSpringer Science and Business Media Deutschland GmbH
Pages447-478
Number of pages32
ISBN (Print)9783031306198
DOIs
StatePublished - 2023
Event42nd Annual International Conference on Theory and Applications of Cryptographic Techniques, EUROCRYPT 2023 - Lyon, France
Duration: 23 Apr 202327 Apr 2023

Publication series

NameLecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)
Volume14006 LNCS
ISSN (Print)0302-9743
ISSN (Electronic)1611-3349

Conference

Conference42nd Annual International Conference on Theory and Applications of Cryptographic Techniques, EUROCRYPT 2023
Country/TerritoryFrance
CityLyon
Period23/04/2327/04/23

Bibliographical note

Publisher Copyright:
© 2023, International Association for Cryptologic Research.

Fingerprint

Dive into the research topics of 'Fully Adaptive Decentralized Multi-Authority ABE'. Together they form a unique fingerprint.

Cite this