Membership Proof in ZKT protocol is a mechanism designed to verify the legitimacy of transaction participants. It uses Plonk and Plookup, two cryptographic techniques, to handle the verification process. This method addresses the challenge of maintaining privacy in transactions while ensuring they are conducted within a compliant framework.
The Membership Proof works by validating that each transaction input belongs to a set that has been pre-verified for compliance. This set is publicly available, allowing for the verification process to be transparent. The proof does not disclose the specific details of the transactions, thereby maintaining the privacy of users.
The adoption of Plookup in the Membership Proof is a response to the limitations of traditional Merkle proof methods, which typically see an increase in circuit size with a large number of proofs. Plookup maintains a constant circuit size regardless of the number of proofs, which makes the verification process more efficient in terms of computation and time.
The Membership Proof mechanism is an integral part of the ZKT protocol, ensuring that transactions are both private and compliant with regulatory requirements.