Cisco Cisco Email Security Appliance C160 Mode D'Emploi

. If you find that the verification is effective, then you can use SPF/SIDF verification 

as a basis for deciding whether to drop or bounce emails for this specified group of senders. 

Create a mail flow policy for SPF/SIDF verification. Enable SPF/SIDF verification for the mail flow 
policy on an incoming listener. For information about enabling SPF/SIDF, see 

Create a sender group for SPF/SIDF verification and use a naming convention to indicate SPF/SIDF 
verification. For information about creating sender groups, see the “Configuring the Gateway to Receive 
Mail” chapter.

Create an 

spf-status

 content filter for each type of SPF/SIDF verification. Use a naming convention to 

indicate the type of verification. For example, use “SPF-Passed” for messages that pass SPF/SIDF 
verification, or “SPF-TempErr” for messages that weren’t passed due to a transient error during 
verification. For information about creating an 

spf-status

 content filter, see 

After you process a number of SPF/SIDF-verified messages, click Monitor > Content Filters to see how 
many messages triggered each of the SPF/SIDF-verified content filters. 

Domain-based Message Authentication, Reporting and Conformance (DMARC) is a technical 
specification created to reduce the potential for email-based abuse. DMARC standardizes how email 
receivers perform email authentication using SPF and DKIM mechanisms. To pass DMARC verification, 
an email must pass at least one of these authentication mechanisms, and the Authentication Identifiers 
must comply with RFC 5322.

AsyncOS for Email allows you to:

Verify incoming emails using DMARC.

Define profiles to override (accept, quarantine, or reject) domain owners’ policies.

Send feedback reports to domain owners, which helps to strengthen their authentication 
deployments.

Send delivery error reports to the domain owners if the DMARC aggregate report size exceeds 10 
MB or the size specified in the RUA tag of the DMARC record.

AsyncOS for Email can handle emails that are compliant with the DMARC specification as submitted 
to Internet Engineering Task Force (IETF) on March 31, 2013. For more information, see