Architecture & Data Flow — AirLink Mobile SDK

The AirLink SDK is a modular, on-device mobile SDK for document capture, biometric matching, credential issuance/verification, and integration with travel/identity ecosystems.

Diagram

Core Components

• Mobile App (Host Application)
  Integrates the AirLink SDK and manages passenger interactions, including check-in, identity verification, and credential presentation.

• AirLink SDK Modules
  • Biometric Module
    On-device selfie capture, liveness detection, and 1:1 facial matching.
  • Document & Credential Verification
    MRZ/OCR scanning, NFC passport chip reading, and digital credential verification.
  • External Services Integration
    Adapters for IATA services (Timatic AutoCheck, Contactless Travel Directory), national ID verification, and third-party APIs.
  • Digital Wallet
    Secure storage and retrieval of verifiable credentials for use across the travel journey.
• External Systems
  • IATA Services (Timatic AutoCheck, Contactless Travel Directory)
  • National ID Verification (e.g., eVerify)
  • Airport Systems (biometric bag-drop, touchless security, boarding gates)

Data Flow

1. Passenger Check-In
   The passenger launches the airline app and begins the check-in process. The app provides itinerary and boarding pass data to the AirLink SDK.

2. Travel Requirements & Airport Capability Check
   • AirLink queries the IATA Contactless Travel Directory to determine biometric capabilities at departure, transit, and arrival airports.
   • It checks Timatic AutoCheck to validate travel document requirements, visa rules, and health regulations based on the passenger’s itinerary.
3. Identity Verification & Document Collection
   • The SDK guides the user through capturing their passport, national ID, or other required travel document using OCR and NFC technology.
   • A selfie is captured with liveness detection, followed by a 1:1 facial match against the document photo.
   • Documents are verified using AI-based document forensic inspection or external system validation
4. Credential Issuance
   • Based on verified identity and travel eligibility, AirLink issues verifiable credentials (e.g., Digital Travel Credential (DTC), journey pass).
   • Credentials are stored securely in the on-device digital wallet for later use.
5. Biometric Enrollment for Airport Use
   • With user consent, AirLink facilitates off-airport enrollment into supported airport biometric systems.
   • This enables touchless experiences at bag-drop, security, and boarding—without needing to present physical documents again.

Security & Privacy

• On-Device Processing
  All biometric and document data is processed locally to protect user privacy.

• Secure Storage
  Sensitive data is encrypted using platform-native secure storage (Keychain on iOS, EncryptedSharedPreferences on Android).

• Secure Communication
  All network traffic is encrypted via HTTPS, with authentication tokens stored securely.

• Privacy-First Design
  Built on decentralized identity principles, AirLink ensures user control over personal data and supports selective disclosure via verifiable credentials.

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Refer to the Architecture Overview and platform-specific SDK guides for implementation details and integration best practices.