The Horcrux Protocol: A Method for Decentralized Biometric-based Self-sovereign Identity

Most user authentication methods and identity proving systems rely on a centralized database. Such information storage presents a single point of compromise from a security perspective. If this system is compromised it poses a direct threat to users digital identities. This paper proposes a decentralized authentication method, called the Horcrux1 protocol, in which there is no such single point of compromise. The protocol relies on decentralized identifiers (DIDs) under development by the W3C Verifiable Claims Community Group and the concept of selfsovereign identity. To accomplish this, we propose specification and implementation of a decentralized biometric credential storage option via blockchains using DIDs and DID documents within the IEEE 2410–2017 Biometric Open Protocol Standard (BOPS).1The term “horcrux” comes from the Harry Potter book series in which the antagonist (Lord Voldemort) places copies of his soul into physical objects. Each object is scattered and/or hidden to disparate places around the world. He cannot be killed until all horcruxes are found and destroyed.