Session approach
In the session approach, the Attestation API generates and tracks the server nonce on behalf of the RP. The session reference returned by the API enforces single-use. The RP and Device may decide to also generate device nonce. In that case, the final nonce is computed on device and Attestation API.
Properties:
- The Attestation API enforces single-use — a session can only be verified once.
- The Attestation API controls the expiration of attestation session.
- The RP holds only the session reference between calls; the actual server nonce is never stored at RP.
- Two API calls per attestation (init + verify).