Privacy-Preserving PayString Service

Flaviene Scheidt de Cristo, Wazen M. Shbair, Lucian Trestioreanu, Aanchal Malhotra, Radu State

Abstract: PayString is an initiative to make payment identifiers global and human-readable, facilitating the exchange of payment information. However, the reference implementation lacks privacy and security features, making it possible for anyone to access the payment information as long as the PayString identifier is known. We propose an innovative solution, named PayStringSecure, for this issue by integrating a privacy layer based on Self-Sovereign Identity (SSI), Decentralized Identifier (DID) and Verifiable Credential (VC) to the PayString protocol. A working prototype has been developed to enrich the protocol with the new features.