Proof Carrying Data (PCD) zkpassport

Overview

This project focuses on integrating zkpassport and zupass to store and manage Proof Carrying Data (PCD) of users. Zupass is a user-centric app based on PCD SDK framework and provides a wallet-like interface for managing proofs and user-self-controlled data.

First version of system design

System Architecture

The system consists of several key components that work together to provide secure, privacy-preserving identity verification and ticket management:

1. zkpassport-native-app

• Functionality: Scans physical passports and generates zero-knowledge proofs
• Features:
  • Passport scanning interface
  • Proof generation using zero-knowledge cryptography

This is built by zkpassport team, we are using zkpassport-sdk to jump into zkpassport-native-app.

2. client

• Functionality: A service handling requests between components
• Key Services:
  • Route/diff service - Determines what data needs to be verified
    • Age verification: Proves a user is above a certain age without revealing the exact age
    • Nationality verification: Confirms nationality without exposing full passport details
    • personhood verification: Confirms the user is a unique human
  • zkpassport-sdk integration - Processing passport data securely
  • Integrate zupass and deal with PCDs

3. zupass

• Functionality: User-facing wallet for managing identity proofs
• Key Services:
  • Access controls for applications requiring verification
  • Maintains privacy while enabling verification

4. hyle (ticket marketplace; blockchain)

• Functionality: Decentralized ticket verifier
• Key Features:
  • Buy Ticket:
    1. Verifies nationality proof
    2. Maps to user (creates unique ID)
    3. Sets ticket_is_used = false
  • Spend Ticket:
    1. Verifies passport identity
    2. Checks user owns ticket
    3. Updates ticket_is_used from false to true
  • Resell/Transfer:
    1. Verifies passport identity
    2. Checks user owns ticket
    3. User repays the discount (if the nationality doesn't match)
    4. Transfers ticket to new owner

Todos and Status

• Writing frontend and api endpoints to handle different zkpassport-sdk
• Implement PCD storage integration with encryption and access controls
• Develop hyle ticket marketplace features (buy, spend, transfer)
• Create user flows for passport scanning and verification
• Add monitoring and security auditing for proof verification

Development

yarn install
yarn dev:client

Reference

zupass

projects

• zukyc
• Building Verifiable Computation

videos

• What is PODs?
• A Deep Dive into ZK Proofs of PODs
• Building Consumer Apps with Programmable Cryptography
• Behind Zupass: Applied Cryptography For Consumers
• Zupass, identity and credentials beyond proof of personhood