TLS.
also: TLS handshake · SSL/TLS · HTTPSTransport Layer Security: encrypts and authenticates a connection; the handshake checks the server's certificate and agrees session keys.
the two-minute refresher
- The client verifies the server's certificate chain up to a trusted root CA.
- Both sides agree on symmetric session keys; then traffic is encrypted and tamper-evident.
- TLS 1.3 needs 1 RTT for the handshake (TLS 1.2 needed 2).
- HTTPS is HTTP over TLS; terminating TLS at a load balancer lets it read requests.