Curve25519, which is what WireGuard uses. The private half never leaves the
machine and is written to a file of its own, so the interface configuration the
mesh composes can point at it without ever carrying it.
Separate from the identity keypair on purpose. One signs messages to the mesh
and the other encrypts traffic between nodes -- different things verified by
different parties at different times, and a key used for two purposes is one
rotation away from breaking the other.
jschoubben
732905a6a6