Cisco Cisco Email Security Appliance C680 User Guide

If you cannot configure the appliance as the first machine receiving email from 
the Internet, you can still exercise some of the security services available on the 
appliance. Refer to 

 for more information. 

When you use the Cisco IronPort appliance as your SMTP gateway: 

The Mail Flow Monitor feature (see “Using Email Security Monitor” in the 
Cisco IronPort AsyncOS for Email Daily Management Guide) offers 
complete visibility into all email traffic for your enterprise from both internal 
and external senders. 

LDAP queries (“LDAP Queries” in the Cisco IronPort AsyncOS for Email 
Advanced Configuration Guide) for routing, aliasing, and masquerading can 
consolidate your directory infrastructure and provide for simpler updates. 

Familiar tools like alias tables (“Creating Alias Tables” in the Cisco IronPort 
AsyncOS for Email Advanced Configuration Guide), domain-based routing 
(“The Domain Map Feature” in the Cisco IronPort AsyncOS for Email 
Advanced Configuration Guide), and masquerading (“Configuring 
Masquerading” in the Cisco IronPort AsyncOS for Email Advanced 
Configuration Guide) make the transition from Open-Source MTAs easier. 

Malicious email senders actively search public DNS records to hunt for new 
victims. You need to ensure that the Cisco IronPort appliance is registered in 
DNS, if you want to utilize the full capabilities of IronPort Anti-Spam, Outbreak 
Filters, McAfee Antivirus and Sophos Anti-Virus. To register the Cisco IronPort 
appliance in DNS, create an A record that maps the appliance’s hostname to its IP 
address, and an MX record that maps your public domain to the appliance’s 
hostname. You must specify a priority for the MX record to advertise the Cisco 
IronPort appliance as either a primary or backup MTA for your domain.