Symantec 10744983 - Mail Security 8320, Administration Manual

Page: 113 / 249

Automatic expansion of subdomains
When evaluating domain name matches, Symantec Mail Security automatically
expands the specified domain to include subdomains. For example, Symantec Mail
Security expands example.com to include biz.example.com and, more generally,
*@*.example.com, to ensure that any possible subdomains are allowed or blocked
as appropriate.
Logical connections and internal mail servers: non-gateway deployments
When deployed at the gateway, Symantec Mail Security can reliably obtain the
physical or peer IP connection for an incoming message and compare it to entries
in the Allowed Senders Lists and Blocked Senders Lists. If deployed elsewhere in
your network, for example, downstream from the gateway MTA, Symantec Mail
Security works with the logical IP connection. The system determines the logical
connection by obtaining the address that was provided as an IP connection address
when the message entered your network. Your network is based on the internal
address ranges that you supply to Symantec Mail Security when setting up your
Scanners. This is why it is important that you accurately identify all the internal
mail hosts in your network.
For more information, see Configuring internal mail hosts on page 25.
Adding senders to Blocked Senders Lists
To prevent undesired messages from being delivered to inboxes, you can add
specific email addresses, domains, and connections to your Blocked Senders Lists.
To add domain-based, IP-based, and Third Party Services entries to your Blocked
Senders Lists
1
In the Control Center, click Policies > Sender Groups.
2 Click one of the Blocked Sender groups.
3
Click Add.
4
On the Add Sender Group Members page, supply the information appropriate
for the current Blocked Sender group.
See “How Symantec Mail Security identifies senders and connections”
on page 111.
5 Click Save.
6
Modify the default action for messages originating from blocked senders
(Delete the message) if desired.
7
Click Save on the Edit Sender Group page.
113 Configuring email filtering
Managing Email Firewall policies