CHLOM Metaprotocol — DID & Biometric Identity Layer — Unified Architecture & Lifecycle Management

This document details the Decentralized Identifier (DID) & Biometric Identity Layer of the CHLOM Metaprotocol, forming the core of its authentication, authorization, and identity persistence model across Web2, Web3, multi-chain, and enterprise environments. This architecture is patent-pending under CrownThrive, LLC, and all usage or integration requires active licensing via crownthrive.com.

1. Purpose & Scope

The DID & Biometric Identity Layer establishes a unified, verifiable, and privacy-preserving identity system that binds:

• Decentralized Identifiers (DIDs) for persistent cross-platform identity.
• Biometric fingerprints for cryptographic proof of uniqueness and ownership.
• Multi-sig enforcement using biometric and cryptographic key pairing.
• ZK-enabled credential verification without exposing raw biometric data.

This layer ensures:

• Tamper-proof linkage between user, device, and credential.
• Persistence of identity state across all CHLOM-enabled ecosystems.
• Interoperability between DID registries, identity wallets, and on-chain smart contracts.

2. Core Components

1. DID Registry Contract: Maintains verifiable identifiers and associated public keys.
2. Biometric Hash Service: Converts biometric scans into irreversible cryptographic hashes.
3. Binding Oracle: Links biometric hashes to DIDs with compliance attestation.
4. VC Issuer Module: Generates verifiable credentials for licensing and governance participation.
5. Revocation Registry: Allows on-chain revocation of compromised identities.
6. Interoperability Gateway: Bridges DID and VC formats across chains and identity standards.

3. Lifecycle Management

1. Enrollment: User submits biometric scan → Biometric Hash Service → DID Registry entry.
2. Binding: Binding Oracle verifies fingerprint + DID pairing under compliance rules.
3. Credential Issuance: VC Issuer generates ZK-enabled verifiable credential.
4. Verification: Counterparty verifies credential via on-chain/off-chain ZK proof.
5. Revocation/Rotation: DID key or biometric hash updated in case of compromise.
6. Audit Anchoring: Lifecycle events are anchored to IPFS and blockchain for immutable logging.

4. Solidity DID Registry Example

// SPDX-License-Identifier: BUSL-1.1
pragma solidity ^0.8.24;

contract DIDRegistry {
    struct Identity {
        address owner;
        bytes32 biometricHash;
        bool active;
    }

    mapping(bytes32 => Identity) public identities;

    event DIDRegistered(bytes32 indexed did, address owner);
    event BiometricBound(bytes32 indexed did, bytes32 biometricHash);

    function registerDID(bytes32 did) external {
        require(identities[did].owner == address(0), "DID_EXISTS");
        identities[did] = Identity(msg.sender, 0x0, true);
        emit DIDRegistered(did, msg.sender);
    }

    function bindBiometric(bytes32 did, bytes32 biometricHash) external {
        require(msg.sender == identities[did].owner, "NOT_OWNER");
        identities[did].biometricHash = biometricHash;
        emit BiometricBound(did, biometricHash);
    }
}

5. Off-Chain Biometric Hashing Example

import hashlib

def generate_biometric_hash(fingerprint_data):
    # fingerprint_data should be a securely captured and normalized template
    return hashlib.sha256(fingerprint_data.encode('utf-8')).hexdigest()

6. Security & Compliance

• No raw biometric storage — only irreversible hashes stored on-chain.
• Multi-factor binding (biometric + private key + DID).
• ZK-based selective disclosure for privacy-preserving verification.
• Jurisdictional compliance enforcement in Binding Oracle rulesets.

7. Patent & Licensing Protections

The DID & Biometric Identity Layer, including its multi-chain persistence, ZK verification model, and biometric hash binding, is patent-pending. Unauthorized implementation is prohibited without explicit licensing from CrownThrive, LLC.

Next: CHLOM Verifiable Credentials Framework — Credential Types, Issuance, and ZK Verification.