In 2023, Signal was the first mainstream messenger to enable post-quantum cryptography. We’re still ahead of the (elliptical) curve, implementing a new hybrid PQ ratchet ensuring Forward Secrecy & Post-Compromise Security even in a post-quantum world. 

Signal Messenger
Signal Protocol and Post-Quantum Ratchets
We are excited to announce a significant advancement in the security of the Signal Protocol: the introduction of the Sparse Post Quantum Ratchet (S...
