Distributed public-key cryptography from weak secrets

Abdalla, Michel , Boyen, Xavier, Chevalier, Céline , & Pointcheval, David (2009) Distributed public-key cryptography from weak secrets. Lecture Notes in Computer Science, 5443, pp. 139-159.

View at publisher


We introduce the notion of distributed password-based public-key cryptography, where a virtual high-entropy private key is implicitly defined as a concatenation of low-entropy passwords held in separate locations. The users can jointly perform private-key operations by exchanging messages over an arbitrary channel, based on their respective passwords, without ever sharing their passwords or reconstituting the key.

Focusing on the case of ElGamal encryption as an example, we start by formally defining ideal functionalities for distributed public-key generation and virtual private-key computation in the UC model. We then construct efficient protocols that securely realize them in either the RO model (for efficiency) or the CRS model (for elegance).

We conclude by showing that our distributed protocols generalize to a broad class of “discrete-log”-based public-key cryptosystems, which notably includes identity-based encryption. This opens the door to a powerful extension of IBE with a virtual PKG made of a group of people, each one memorizing a small portion of the master key.

Impact and interest:

10 citations in Scopus
7 citations in Web of Science®
Search Google Scholar™

Citation counts are sourced monthly from Scopus and Web of Science® citation databases.

These databases contain citations from different subsets of available publications and different time periods and thus the citation count from each is usually different. Some works are not in either database and no count is displayed. Scopus includes citations from articles published in 1996 onwards, and Web of Science® generally from 1980 onwards.

Citations counts from the Google Scholar™ indexing service can be viewed at the linked Google Scholar™ search.

Full-text downloads:

42 since deposited on 26 Mar 2014
7 in the past twelve months

Full-text downloads displays the total number of times this work’s files (e.g., a PDF) have been downloaded from QUT ePrints as well as the number of downloads in the previous 365 days. The count includes downloads for all files if a work has more than one.

ID Code: 69182
Item Type: Journal Article
Refereed: Yes
Additional Information: Proceedings of the 12th International Conference on Practice and Theory in Public Key Cryptography, Irvine, CA, USA, March 18-20, 2009.
Additional URLs:
Keywords: Data Encryption , Algorithm Analysis and Problem Complexity , Information security
DOI: 10.1007/978-3-642-00468-1_9
ISSN: 1611-3349 (online) 0302-9743 (print)
Divisions: Current > Schools > School of Electrical Engineering & Computer Science
Current > QUT Faculties and Divisions > Science & Engineering Faculty
Copyright Owner: Copyright 2009 Springer Berlin Heidelberg
Copyright Statement: Author's Pre-print: author can archive pre-print (ie pre-refereeing)
Author's Post-print: author can archive post-print (ie final draft post-refereeing)
Publisher's Version/PDF: author cannot archive publisher's version/PDF
Deposited On: 26 Mar 2014 00:00
Last Modified: 17 Jul 2014 12:57

Export: EndNote | Dublin Core | BibTeX

Repository Staff Only: item control page