Which components are required when encrypting SMTP with TLS on a Cisco Secure Email Gateway...

To encrypt SMTP with TLS on a Cisco Secure Email Gateway appliance when the sender requires TLS verification, the components that are required are an X.509 certificate and matching private key from a CA. The certificate must be signed by a trusted CA and contain the domain name or IP address of the listener in the Subject or Subject Alternative Name fields. The private key must be unencrypted and match the certificate.  References : [Cisco Secure Email Gatew ay Administrator Guide - Configuring TLS]