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NFC Tag Registry

The NFC Tag Registry enables users to register hardware recovery tokens—such as NFC cards, stickers, or embedded secure elements—as part of their decentralized recovery strategy. These tags act as verifiable recovery items and can be used in multi-factor recovery policies without requiring custodial services or passphrases.

Purpose​

NFC tags offer a simple, user-friendly way to:

  • Anchor a recovery factor to a physical device
  • Use common, inexpensive hardware (e.g. NTAG-based tags)
  • Extend recovery logic into 2-of-3 or higher threshold configurations

The registry binds an NFC tag’s unique ID to an on-chain item account, used by the extended recovery pallet.

Registration Flow​

  1. Scan & Extract UID
    During setup, the mobile app scans the NFC tag and reads its unique hardware identifier (UID). This ID is never stored in plaintext on-chain.

  2. Hash and Derive Item Account
    The UID is hashed and mapped to a deterministic item account ID. This ensures that the NFC tag can later be verified by re-scanning, without exposing metadata.

  3. Register with Root Identity
    A transaction is sent to the NFC Tag Registry pallet within the trusted TEE runtime:

    • Associates the derived item account ID with the user’s proxy/root identity
    • Marks the tag as an eligible recovery factor

Security Considerations​

  • No private data stored on-chain: All tag identifiers are hashed client-side before registration.
  • Offline-compatible: NFC tags do not require active electronics or connectivity.
  • TEE-verified: Registration and future verification are processed securely inside the TEE.

Usage in Recovery​

Once registered, the NFC tag may be used to:

  • Satisfy threshold-based recovery policies (e.g., 2-of-3)
  • Serve as a physical factor in biometric-plus-hardware authentication
  • Be combined with cloud-backed VCA tokens or other secure files

The NFC Tag Registry allows everyday physical objects to become secure, verifiable recovery devices—enhancing resilience without compromising user sovereignty.