3Com SUPERSTACK 3 WEBCACHE 3000 User Manual page 148

148 C 10: U
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When a client computer attempts to access a Web site, the Webcache
applies the following rules in the order listed:
1 Web Client Blocking — If Web Client Blocking has been activated the
Webcache checks to see if the client is on the Web Client Blocking List.
Unauthorized clients will be filtered. See
page 161 for more information.
2 Filter Exclusion — The Webcache checks to see if the client is on the Filter
Exclusion list. For authorized clients, further rules will be bypassed and
the clients granted access to the Website. See
page 166 for more information.
3 Allow and Deny Lists — The Webcache checks to see if the Web site
being accessed has been expressly allowed or blocked (denied) by an
administrator. If the Web site is on the Allow List, the user is granted
access. If it is on the Deny List the access is blocked. If the site is not listed
then the Webcache looks at the next rule. See
and Deny Lists"
If a domain name appears in both the Allow and Deny Lists then it will be
denied. To stop the site from being denied, remove it from the Deny List.
4 Keyword Blocking — The Webcache checks all the entries in the Keyword
Blocking list against the URL of the Web site for a partial match. If a
partial or complete match is found then the site is filtered, otherwise the
Webcache continues with the next rule. See
page 174 for more information.
It is important to use caution when adding keywords to the Keyword
Blocking list as you may filter sites other than you intend. For example,
blocking the word breast may filter sites on breast cancer as well as
objectionable or pornographic sites.
5 Web Site Filter Subscription Status — If the Web Site Filter is enabled but
its subscription has expired then the Webcache will filter according to the
Default Rule (Allow All or Deny All) otherwise it will continue with the
next rule. See "Default Rule"
the Default Rule.
6 3Com Web Site Filter — The Webcache compares the Web site against all
the sites in the categories that are in the currently active Filter Policy. See
below for setup and configuration information and
Filtering Policies"
Categories.
on page 169 for more information.
on page 159
on page 152 for information on the Web Site Filter
"Web Client Blocking"on
"Filter Exclusions"
"Setting Up Allow Lists
"Keyword Blocking"
for more information about
"Setting Up
on
on