Symantec 10744983 - Mail Security 8320, Руководство администратора

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Table 4-13
Attachment characteristics for attachment lists
Examples Description Characteristic
Microsoft Word for
Windows
Specifies an attachment type based on direct
inspection of the type of file. You can use
this to match files whose extensions may not
accurately reflect their true file types. Each
file type is a member of a specific file class.
True file type
Word Processor
Document
Specifies an attachment type based on the
class of file. You can use this to match files
whose extensions may not match their true
file classes.
True file class
oxy
oxygen
oxygen.txt
Part or all of a filename. A partial match for
a file will match a file, such as “oxy” for
“oxygen.txt”.
File name
.txt
.exe
.text
.zip
A period followed by usually three letters at
the end of a file that, by convention,
indicates the type of the file.
Extension
text/plain
image/gif
application/msword
application/octet-stream
The MIME type of the attachment in the
email message. MIME is a standard for email
attachments.
MIME-type
For a technical description of MIME, see the following RFC:
http://www.ietf.org/rfc/rfc2045.txt
To add an attachment list
1
In the Control Center, click Policies > Attachment Lists.
2
Click Add.
3 In the Attachment list name box, type a name for the attachment list.This
is the name that appears on the Attachment Lists page and as the Attachment
List in the Conditions section when configuring a policy.
4
In the Configure Attachment Types box, either:
■
Click the first radio button to match files based on the actual type or class
of the file, even if that type or class does not match the extension. Choose
125 Configuring email filtering
Managing policy resources