Title
Public-key encryption in a multi-user setting: security proofs and improvements
Abstract
This paper addresses the security of public-key cryptosystems in a "multi-user" setting, namely in the presence of attacks involving the encryption of related messages under different public keys, as exemplified by Håstad's classical attacks on RSA. We prove that security in the single-user setting implies security in the multi-user setting as long as the former is interpreted in the strong sense of "indistinguishability," thereby pin-pointing many schemes guaranteed to be secure against Håstad-type attacks. We then highlight the importance, in practice, of considering and improving the concrete security of the general reduction, and present such improvements for two Diffie-Hellman based schemes, namely El Gamal and Cramer-Shoup.
Year
DOI
Venue
2000
10.1007/3-540-45539-6_18
EUROCRYPT
Keywords
DocType
Volume
el gamal,stad-type attack,security proof,general reduction,public-key cryptosystems,concrete security,related message,strong sense,different public key,multi-user setting,classical attack,public-key encryption,single-user setting,public key encryption,public key
Conference
1807
ISSN
ISBN
Citations 
0302-9743
3-540-67517-5
225
PageRank 
References 
Authors
19.09
9
3
Search Limit
100225
Name
Order
Citations
PageRank
Mihir Bellare1164371481.16
Alexandra Boldyreva22297114.80
Silvio Micali3114342581.31