WatchGuard Technologies FireboxTM System 4.6 User Manual

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Service precedence
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If you are using the HTTP proxy service because you want to use WebBlocker, 
follow the procedure in the next section. Otherwise, enable HTTP proxy 
properties according to your security policy preferences.
For detailed descriptions of HTTP proxy options, see the 
Reference Guide.
4
Click  the  Safe Content tab.
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Add or remove properties according to your security policy preferences. Click 
OK.
Service precedence
Precedence is generally given to the most specific service and descends to the most 
general service. However, exceptions exist. There are three different precedence 
groups for services:
• The “Any” service (see the Online Help system for information about the 
“Any” packet filter service). This group has the highest precedence.
• IP and ICMP services and all TCP/UDP services that have a port number 
specified. This group has the second highest precedence and is the largest of the 
three.
• “Outgoing” services that do not specify a port number (they apply to any port). 
This group includes Outgoing TCP, Outgoing UDP, and Proxy.
“Multiservices” can contain subservices of more than one precedence group. 
“Filtered-HTTP” and “Proxied-HTTP,” for example, contain both a port-specific TCP 
subservice for port 80 as well as a nonport subservice that covers all other TCP 
connections. When precedence is being determined, individual subservices are given 
precedence according to their group (described previously) independent of the other 
subservices contained in the multiservice.
Precedence is determined by group first. Services from a higher precedence group 
always have higher precedence than the services of a lower-precedence group, 
regardless of their individual settings (for example, the lowest precedence “Any” 
service will take precedence over the highest precedence Telnet service).
The precedences of services that are in the same precedence group are ordered from 
the most specific services (based on source and destination targets) to the least 
specific service. The method used to sort services is based on the specificity of targets, 
from most specific to least specific. The following order is used:
Zip files are denied when you deny Java or ActiveX applets, because zip files 
often contain these applets.
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