Explanation
The Cisco SD-WAN control plane has been designed with network and device security in mind. The foundation of the control plane is one of two security protocols derived from SSL (Secure Sockets Layer)-the Datagram Transport Layer Security (DTLS) protocol and the Transport Layer Security (TLS) protocol.
Reference:
https://www.cisco.com/c/en/us/td/docs/routers/sdwan/configuration/security/vedge/security-book/security-overvi