Protecting Against E-Mail Spam - NETGEAR STM150 Appliance Reference Manual

ProSecure Web/Email Security Threat Management (STM) Appliance Reference Manual
Table 4-6. E-mail Filter Settings (continued)
Setting Description (or Subfield and Description)
Filter by File Type
File Extension By default, the File Extension field lists the most common file extensions that will be
detected. You can manually add or delete extensions. Use commas to separate
different extensions. You can enter a maximum of 40 file extensions; the maximum
total length of this field, excluding the delimiter commas, is 160 characters.
To narrow down the extensions to specific categories only, first delete the extensions
from the File Extension field, and then make a selection from the pull-down menu:
• None. The most common file extensions are listed without being narrowed down to a
category. This is the default setting.
• Executables. The File Extension field lists executable file extensions.
• Audio/Video. The File Extension field lists audio and video file extensions.
• Compressed Files. The File Extension field lists compressed file extensions.
Action SMTP
POP3
IMAP
Filter by File Name
File Name Enter the file names that will be detected. For example, to block the Netsky worm
(which normally arrives as netsky.exe), enter netsky.exe. You can enter a maximum of
20 file names. Use commas to separate multiple file names. The maximum total length
of this field is 400 characters, excluding the delimiter commas.
Action SMTP
POP3
IMAP
3. Click Apply to save your settings.

Protecting Against E-mail Spam

The STM integrates multiple anti-spam technologies to provide comprehensive protection against
unwanted e-mail. You can enable all or a combination of these anti-spam technologies. The STM
implements these spam prevention technologies in the following order:
1. Whitelist. E-mails from the specified sources or to the specified recipients are not considered
spam and are accepted.
2. Blacklist. E-mails from the specified sources are considered spam and are blocked.
Content Filtering and Optimizing Scans
From the pull-down menu, specify an action when an e-mail attachment
with a file extension that is defined in the File Extension field is detected.
The pull-down menu selections and defaults are the same as the ones for
the "Filter by Password-Protected Attachments (ZIP, RAR, etc.)"
above.
From the pull-down menu, specify an action when an e-mail attachment
with a name that is defined in the File Name field is detected. The pull-down
menu selections and defaults are the same as the ones for the
Password-Protected Attachments (ZIP, RAR, etc.)"
v1.0, September 2009
section
"Filter by
section above.
4-15