Application US20210081935

SYSTEM AND METHOD FOR PROVIDING PRIVACY-PRESERVING PROOFS OF MEMBERSHIP

A system and method for providing privacy-preserving proofs of membership are disclosed. A particular embodiment includes: a network node in data communication with other network nodes via a data network, the network node having a secure processing enclave, the enclave configured to include: at least one isolated memory device, processing logic isolated from operating system (OS) calls, and a remote attestation capability, the network node further configured to maintain a first Merkle tree to support transaction output proof-of-membership queries, and a sorted second Merkle tree to support key image proof-of-non-membership queries; a wallet configured as executable code on a client device, the wallet configured to establish a secure data communication with the network node and to request validation of a transaction by sending a transaction output proof-of-membership and a key image proof-of-non-membership to the network node; and the network node configured to receive the transaction output proof-of-membership and the key image proof-of-non-membership within the enclave from the client device, the enclave configured to use the transaction output proof-of-membership to traverse the first Merkle tree to validate that a corresponding transaction is a member of a transaction ledger, the enclave configured to use the key image proof-of-non-membership to traverse the second Merkle tree to validate that a corresponding key image is not a member of the transaction ledger.