User Guide

41-2
AsyncOS 9.1.2 for Cisco Email Security Appliances User Guide
Chapter 41 Optimizing the Appliance for Outbound Mail Delivery Using D-Mode
Feature Summary: D-Mode for Optimized Outbound Delivery
Standard Features Disabled in D-Mode-Enabled Appliances
• IronPort anti-spam scanning and on or off box spam quarantining — Because anti-spam scanning
pertains mostly to incoming mail, the IronPort Anti-Spam scanning engine is disabled. The
Anti-Spam chapter is, therefore, not applicable.
• Outbreak Filters — Because the Outbreak Filters feature is used to quarantine incoming mail, this
feature is disabled on D-Mode-enabled appliances. Information in the Outbreak Filters chapter is,
therefore, not applicable.
• SenderBase Network Participation capabilities — Because SenderBase Network Participation
reports information about incoming mail, this feature is disabled on D-Mode-enabled appliances.
Information about SenderBase Network Participation is, therefore, not applicable.
• Reporting — Reporting is limited. Some reports are not available, and the reporting that does occur
is set to run at a very limited level for performance reasons.
Note The totals shown in the Email Security Monitor Overview report for D-Mode-enabled
appliances may erroneously include spam and suspect spam counts, even though these
features are disabled on D-Mode-enabled appliances.
• RSA Data Loss Prevention — RSA DLP scanning for outgoing messages is disabled on
D-Mode-enabled appliances.
Standard Features Applicable to D-Mode-Enabled Appliances
Table 41-1 AsyncOS Features Included in D-Mode Enabled Appliances
Feature More Information
Anti-virus scanning
See Chapter 12, “Anti-Virus.”
Domain Key signing
DKIM/Domain Keys is a method for verifying authenticity of email
based on a signing key used by the sender. See Chapter 20, “Email
Authentication.”
Centralized management
See Chapter 39, “Centralized Management Using Clusters.”
Delivery throttling
For each domain, you can assign a maximum number of connections
and recipients that will never be exceeded by the system in a given
time period. This “good neighbor” table is defined through the
destconfig command.
For more information, see Controlling Email Delivery Using
Destination Controls, page 24-42.
Bounce Verification
Verify the authenticity of bounce messages. See Bounce Verification,
page 24-51.
Delegated administration
See Chapter 32, “Distributing Administrative Tasks.”
Trace (debug)
See Debugging Mail Flow Using Test Messages: Trace, page 40-1.