Symantec 10744983 - Mail Security 8320, Руководство администратора

Страница: 119 / 249

Symantec monitors hundreds of thousands of email sources to determine how
much email sent from these addresses is legitimate and how much is spam. Email
from given email sources can then be blocked or allowed based on the source's
reputation value as determined by Symantec. By default, Symantec Mail Security
is configured to incorporate the source information from all three lists comprising
the Sender Reputation Service.
To enable or disable Proxy Senders, Safe Senders, and Suspect Spammers lists
1
In the Control Center, click Policies > Sender Groups.
2
Check or uncheck the boxes for the desired lists.
3
Click Enable or Disable.
Configuring Sender Authentication
Symantec Mail Security can check incoming email for authenticity using the
Sender Policy Framework (SPF) or the Sender ID standard. This can reduce spam
because spammers often attempt to forge the mail server name to evade discovery.
Symantec Mail Security checks the sending IP address against the published DNS
record for the named mail server. If the DNS record includes a hard outbound
email policy (one that requires compliance), and it does not match the sending IP
address, the specified action is taken on the message. If the IP address matches,
or the domain publishes only an informational policy, or does not publish a policy,
no action is taken.
For more information about SPF, see: http://www.openspf.org/
For more information about Sender ID, see: http://www.microsoft.com/senderid
If you add Sender Authentication domains, it's best to specify the highest level
domain possible, such as example.com, because subdomains of the specified
domain will also be tested for compliance.
Warning: Authenticating all domains can lead to significant unnecessary processing
load. Many domains do not publish an outbound email policy, or publish only an
informational policy. Attempting authentication on these domains does not lead
to any action, and will use processing resources, at times excessively.
Authentication is most effective for domains that publish hard policies that are
frequently spoofed in phishing attacks.
To enable sender authentication
1
In the Control Center, click Policies > Sender Authentication.
2
Check Enable Sender Authentication.
119 Configuring email filtering
Configuring Sender Authentication