Barracuda recommends enforcing use of a secure TLS connection to send mail through the Barracuda Email Security Gateway (inbound and outbound) for all domains. To do so, set Force TLS to Yes. SMTP over TLS/SSL defines the SMTP command STARTTLS. This command advertises and negotiates an encrypted channel with the peer for this SMTP connection.
For More Information Please Refer:
You May Also Like to Read: