Cisco Cisco Email Security Appliance C160 Mode D'Emploi

Most customers’ network configurations are represented in the following scenarios. If your network 
configuration varies significantly and you would like assistance planning an installation, please contact 
Cisco Customer Support (see 

). 

The following figure shows the typical placement of the Email Security appliance in an enterprise 
network environment: 

In some scenarios, the Email Security appliance resides inside the network “DMZ,” in which case an 
additional firewall sits between the Email Security appliance and the groupware server.

The following network scenarios are described:

Behind the Firewall: two listeners configuration (

) 

Choose the configuration that best matches your infrastructure. Then proceed to the next section, 

Incoming mail is accepted for the local domains you specify. 

All other domains are rejected. 

External systems connect directly to the Email Security appliance to transmit email for the local 
domains, and the Email Security appliance relays the mail to the appropriate groupware servers (for 
example, Exchange™, Groupwise™, Domino™) via SMTP routes. (See 

Outgoing mail sent by internal users is routed by the groupware server to the Email Security 
appliance. 

The Email Security appliance accepts outbound email based on settings in the Host Access Table 
for the private listener. (For more information, see 

.) 

Only one of the available Ethernet interfaces on the Email Security appliance is required in these 
configurations. However, you can configure two Ethernet interfaces and segregate your internal network 
from your external Internet network connection. 

For more information about assigning multiple IP addresses to the available interfaces, see 

 and