Decoupled and Privacy-Preserving Key Generation in ABE Under the Minimal Disclosure Principle

Summary

Researchers propose a privacy-enhancing key generation protocol for Attribute-Based Encryption, guided by the Minimal Disclosure principle, so users reveal only the attributes needed for authorization. The protocol decouples attribute verification from key issuance, using reusable verifiable attribute tokens and blinded key requests, with a batch verification mechanism to reduce overhead. The authors report proofs of binding and hiding properties, formal verification in the symbolic model with ProVerif, and experiments showing reduced inference leakage and efficiency gains over existing schemes.