# Transport security uses Noise, not TLS

We secure the session with the Noise protocol (an `XX` handshake) using each
device's long-term identity key, rather than mutual TLS with per-device certs.
Noise avoids a CA/cert machinery on a peer-to-peer LAN, maps cleanly onto the
SAS pairing flow, and is light enough for the Odin daemon and Android
(Conscrypt). The pinned trust record and the session key are the *same* key,
simplifying the model.