Signal's New PQ Ratchet
8 hours ago
- #Encryption
- #Quantum Security
- #Signal Protocol
- Signal introduces the Sparse Post Quantum Ratchet (SPQR) to enhance security against quantum computing threats.
- SPQR maintains existing security guarantees like forward secrecy and post-compromise security.
- The Signal Protocol is widely used for end-to-end encryption in messaging apps.
- PQXDH was the first step towards quantum resistance in the Signal Protocol.
- SPQR works alongside the existing Double Ratchet to form the Triple Ratchet.
- The Triple Ratchet combines quantum-safe and classical cryptographic keys for hybrid security.
- Signal ensures backward compatibility and smooth rollout of SPQR without user action.
- Formal verification and research collaborations ensure the protocol's correctness and security.
- Erasure codes are used to efficiently transmit large cryptographic data in small chunks.
- The protocol is designed to resist malicious middlemen and ensure message integrity.