Symantec Mail Security, Руководство администратора

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105 Configuring email filtering
Configuring Sender Authentication
Enabling Open Proxy Senders, Safe Senders, and Suspected
Spammers lists
Symantec continuously compiles and updates the three Sender Reputation
Service lists:
■
Open Proxy Senders
IP addresses that are either open proxies used by spammers or “zombie”
computers that have been co-opted by spammers.
■
Safe Senders
IP addresses from which virtually no outgoing email is spam.
■
Suspected Spammers
IP addresses from which virtually all of the outgoing email is spam.
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 for SMTP 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 for SMTP 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 for SMTP 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