Which three protocols are required when considering firewall rules for email services using a Cisco Email Security Appliance? (Choose three.)
A. SMTP
B. HTTP
C. DNS
D. SNMP
E. FTP
Which three protocols are required when considering firewall rules for email services using a Cisco Email Security Appliance? (Choose three.)
A. SMTP
B. HTTP
C. DNS
D. SNMP
E. FTP