Cryptology ePrint Archive: Report 2003/261

A provably secure ID-based ring signature scheme

Javier Herranz and Germán Sáez

Abstract: Identity-based (ID) cryptosystems avoid the necessity of certificates to authenticate public keys in a digital communications system. This is desirable, specially for these applications which involve a large number of public keys in each execution. For example, any computation and verification of a ring signature scheme, where a user anonymously signs a message on behalf of a set of users including himself, requires to authenticate the public keys of all the members of the set. We use bilinear pairings to design a new ID-based ring signature scheme. We extend to the ID-based scehario some known results about the security of generic ring signature schemes. This allows us to formally prove the security of our scheme, under the assumption that the Computational Diffie-Hellman problem is hard to solve.

Category / Keywords: public-key cryptography / Identity-based schemes, ring signatures, random oracle model

Date: received 18 Dec 2003

Contact author: jherranz at mat upc es

Available format(s): Postscript (PS) | Compressed Postscript (PS.GZ) | PDF | BibTeX Citation

Version: 20031220:164025 (All versions of this report)

Short URL: ia.cr/2003/261