Digital Identity Capability Proof Service (DICPS) is an innovative solution designed for privacy-preserving identity verification utilizing zero-knowledge proofs. This service allows users to validate specific attributes about themselves without disclosing sensitive underlying data. For instance, it enables users to prove they are over 18 without revealing their exact age or to demonstrate that they are licensed professionals without sharing their license specifics.

Key Features

• Privacy-Preserving Verification: Authenticate attributes like age, professional credentials, or clearance levels while ensuring personal data remains confidential.
• Robust Security Framework: Incorporates formal security proofs and a comprehensive adversarial model to safeguard against potential threats.
• Flexible Architecture: Built around core components including an identity registry, credential issuer, and a zero-knowledge proof engine, ensuring scalability and maintainability.

Core Concepts

Zero-Knowledge Proofs

Zero-knowledge proofs facilitate a method where one party (the prover) can convince another party (the verifier) that a statement is true without divulging any additional information about the statement itself.

Use Cases

• Civic Authentication: Verify voting eligibility without revealing personal identity.
• Access Control: Validate security clearance without exposing the exact clearance level.
• Professional Verification: Confirm professional qualifications without disclosing further details.
• Age Verification: Affirm compliance with age-related requirements without revealing specific age.

Architecture Overview

DICPS consists of several core components that interact seamlessly:

1. Identity Registry: Central management of digital identities and associated attributes.
2. Credential Issuer: Responsible for issuing verifiable credentials to identities.
3. ZK Circuit Engine: Generates inputs for different claim types in zero-knowledge proofs.
4. Proof Generator: Constructs zero-knowledge proofs based on claims.
5. Proof Verifier: Validates the authenticity of the generated proofs.
6. Revocation Registry: Operates credential revocations, ensuring a thorough audit trail.

Example Code Usage

To illustrate the functionalities of DICPS, consider the following TypeScript example on how to register an identity, issue a credential, generate a proof of being over 18, and verify the proof:

import { DigitalIdentityProofService, ClaimType } from './src';

// Initialize the service
const service = new DigitalIdentityProofService('My Authority');

// Register an identity
const identity = service.registerIdentity('public_key_123', [
  { name: 'name', value: 'Alice', timestamp: Date.now() }
]);

// Issue a credential
const credential = service.issueCredential(identity.id, [
  { name: 'age', value: 25, timestamp: Date.now() }
]);

// Generate a proof that user is over 18
const proof = await service.generateProof(
  { type: ClaimType.AGE_OVER, parameters: { threshold: 18 } },
  { age: 25, salt: 12345 }
);

// Verify the proof
const result = await service.verifyProof(proof);
console.log('Valid:', result.valid); // true
console.log('Statement:', result.statement); // "User is over 18 years old"

Conclusion

DICPS serves as a robust framework for secure and privacy-preserving identity verification, establishing itself as a powerful tool to enhance digital interactions while ensuring confidentiality and trust.