Cisco Cisco Email Security Appliance C160 Mode D'Emploi

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

The following network scenarios are described:

Behind the Firewall (see 

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

. 

Incoming mail is accepted for the local domains you specify. (See ) 

All other domains are rejected. 

External systems connect directly to the Cisco IronPort appliance to transmit 
email for the local domains, and the Cisco IronPort appliance relays the mail 
to the appropriate groupware servers (for example, Exchange™, 
Groupwise™, Domino™) via SMTP routes. (See “Routing Email for Local 
Domains” in the Cisco IronPort AsyncOS for Email Advanced Configuration 
Guide.) 

Outgoing mail sent by internal users is routed by the groupware server to the 
Cisco IronPort appliance. 

The Cisco IronPort 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 Cisco IronPort appliance 
is required in these configurations. However, you can configure two Ethernet 
interfaces and segregate your internal network from your external Internet 
network connection.