Galileo's Proposed Authentication Algorithm: Part 1 - Bert Hubert's writings
a day ago
- GNSS authentication is needed to prevent PVT spoofing, as current systems broadcast unauthenticated data.
- Galileo's OSNMA uses the TESLA protocol for efficient message authentication with limited bandwidth (40 bits per message).
- Symmetric signatures are used with delayed key disclosure; keys are generated in a chain so each key derives previous ones.
- Occasional public key signatures provide a trust anchor, allowing verification of the entire key chain.
- Receivers must not use disclosed keys to verify future messages; time synchronization is critical to prevent attacks.