Paper 2019/1303

A simpler construction of traceable and linkable ring signature scheme

Wulu Li

Abstract

Traceable and linkable ring signature scheme (TLRS) plays a major role in the construction of auditable privacy-preserving blockchains, as it empowers the auditor with traceability of signers' identities. A recent work by Li gives a modular construction of TLRS by usage of classic ring signature, one-time signature and zero-knowledge proofs, and has security against malicious auditors. In this paper, we introduce sTLRS, a simpler modification of TLRS which is constructed directly from classic ring signature, without any additional one-time signatures or zero-knowledge proofs. sTLRS has public key size reduced by 80% and verification time reduced by over 50%, compared to TLRS. Moreover, we can further modify the sTLRS to achieve anonymity, unforgeability, linkability, nonslanderability and traceability against malicious auditors.