An example operation may include one or more of connecting to a blockchain configured to store an identity trait of a user, retrieving the identity trait from the blockchain, establishing a trust group homomorphism digital signature algorithm (DSA) for the user based on a private key, creating a zero knowledge succinct non-interactive argument of knowledge (zkSNARK) proof constructed based on a DSA of a trait in the trust group homomorphism DSA as witness data, and obtaining further trust information related to the user from the witness data.