Two Certificateless Distributed Ring Signature Schemes
Jiwen Zeng · Dianzi xuebao · 2008
The previous distributed ring signature schemes proposed by Javier Herranz inherit key escrow problem of identity-based public key cryptography.In this paper,we propose two secure certificateless distributed ring signature schemes.Such schemes provide unconditional anonymity to a subset of users who sign a message on behalf of a family of subsets.Our first scheme is based on bilinear pairings,and can be used for general families of possible signing subsets.Its idea comes from that of Schnorr's ring signature scheme.The second scheme is based on Shamir's secret sharing scheme and more efficient for threshold families of subsets.Futhermore,in certificateless scenarios,the trusted authority takes part in generating entities'private keys,but he does not access to these private keys.So our two schemes retain the desirable properties of identity-based distributed ring signature schemes and avoid the inherent escrow of them,therefore actually possess the alleged unforgeability.