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+# Protocol
+
+Protocols ensure the security of platform transmissions, and in a peer-to-peer
+network like Turms, they are essential.
+
+We're not reinventing the wheel, and the **Signal protocol**
+([SignalApp/libsignal](https://github.com/signalapp/libsignal)) is perfectly
+suited to our requirements. This means that the following elements must be
+implemented in the software:
+
+1. **X3DH** (Extended Triple Diffie-Hellman): used to exchange keys securely.