Dynamic Authorization for Private-Keyless Data Custody Services Using Credential-Driven Cryptosystem

This research introduces CREF (Cryptographic Resource Enabled Framework), a system that controls access to stored data based on policies without requiring users to hold private keys (secret numbers used in encryption). Instead of traditional keys, the system uses temporary credential tokens issued by multiple authorities, and it uses lattice-based cryptography (a math method believed to be secure even against quantum computers) to ensure that both credentials and access policies cannot be forged.