In this work we generalize these forking lemmas to the ring signatures' scenario. In a ring signature scheme, a signer in a subset (or {\it ring}) of potential signers produces a signature of a message in such a way that the receiver can verify that the signature comes from a member of the ring, but cannot know which member has actually signed.
We propose a new ring signature scheme, based on Schnorr signature scheme, which provides unconditional anonymity. We use the generalized forking lemmas to prove that this scheme is existentially unforgeable under adaptive chosen-message attacks, in the random oracle model.
Category / Keywords: public-key cryptography / ring signature schemes, unforgeability against chosen-message attacks, random oracle model Date: received 10 Apr 2003 Contact author: jherranz at mat upc es Available format(s): Postscript (PS) | Compressed Postscript (PS.GZ) | PDF | BibTeX Citation Version: 20030411:175017 (All versions of this report) Short URL: ia.cr/2003/067