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To remove an existing custom category, select the category, and then click Delete.
You cannot delete Websense-defined categories.
To change the name or description of a custom category, select the category and
click Rename (see Renaming a custom category, page 205).
To change the filtering action associated with a category in all category filters,
click Override Action (see Making global category filtering changes, page 205).
The Recategorized URLs list shows which recategorized sites (URLs and IP
addresses) have been assigned to this category.
To add a site to the list, click Add URLs. See Recategorizing URLs, page 211,
for further instructions.
To change an existing recategorized site, select the URL or IP address, and
then click Edit.
The Keywords list shows which keywords have been associated with this
category.
To define a keyword associated with the selected category, click Add
Keywords. See Filtering based on keyword, page 207, for further
instructions.
To change an existing keyword definition, select the keyword, and then click
Edit.
In addition to URLs and keywords, you can define Regular Expressions for the
category. Each regular expression is a pattern or template used to associate
multiple sites with the category.
To see or create regular expressions for the category, click Advanced.
To define a regular expression, click Add Expressions (see Using regular
expressions, page 226).
To change an existing regular expression, select the expression, and then click
Edit.
To delete a recategorized URL, keyword, or regular expression, select the item to
remove, and then click Delete.
When you are finished making changes on the Edit Categories page, click OK to
cache the changes and return to the Filter Components page. Changes are not
implemented until you click Save All.
Reviewing all customized category attributes
Use the Filter Components > Edit Categories > View All Custom URLs and
Keywords page to review custom URL, keyword, and regular expression definitions.
You can also delete definitions that are no longer needed.
The page contains 3 similar tables, one for each category attribute: custom URLs,
keywords, or regular expressions. In each table, the attribute is listed next to the name
of the category with which it is associated.
To delete a category attribute, mark the appropriate check box, and then click Delete.
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To return to the Edit Categories page, click Close. If you deleted any items on the
View All Custom URLs and Keywords page, click OK on the Edit Categories page to
cache the changes. Changes are not implemented until you click Save All.
Making global category filtering changes
Use the Filter Components > Edit Categories > Override Action page to change
the action applied to a category in all existing category filters. This also determines the
default action applied to the category in new filters.
Although this change overrides the action applied to the category in all existing filters,
administrators can later edit those filters to apply a different action.
Before changing the filtering settings applied to a category, first verify that the correct
category name appears next to Selected Category. Next, you can:
1. Chose a new Action (Permit, Block, Confirm, or Quota). See Filtering actions,
page 44, for more information.
By default, Do not change current settings is selected for all options on the page.
2. Specify whether or not to Block Keywords. See Filtering based on keyword, page
207, for more information.
3. Specify whether or not to Block File Types, and customize blocking settings. See
Managing traffic based on file type, page 223, for more information.
4. Under Advanced Filtering, specify whether or not to use Bandwidth Optimizer
to manage access to HTTP sites, and customize blocking settings. See Using
Bandwidth Optimizer to manage bandwidth, page 221, for more information.
5. Click OK to return to the Edit Categories page (see Editing categories and their
attributes, page 203). The changes are not cached until you click OK on the Edit
Categories page.
Renaming a custom category
Use the Filter Components > Edit Categories > Rename Category page to change
the name or description associated with a custom category.
Use the Filter name field to edit the category name. The new name must be
unique, and cannot exceed 50 characters.
The name cannot include any of the following characters:
* < > { } ~ ! $ % & @ # . " | \ & + = ? / ; : ,
Use the Description field to edit the category description. The description cannot
exceed 255 characters.
The character restrictions that apply to filter names also apply to descriptions,
with 2 exceptions: descriptions can include periods (.) and commas (,).
Important
Changes made here affect every existing category filter,
except Block All and Permit All.
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When you are finished making changes, click OK to return to the Edit Categories
page. The changes are not cached until you click OK on the Edit Categories page.
Creating a custom category
In addition to using the more than 90 Websense-defined categories in the Master
Database, you can define your own custom categories to provide more precise
filtering and reporting. For example, create custom categories like:
Business Travel, to group sites from approved vendors that employees can use to
buy airplane tickets and make rental car and hotel reservations
Reference Materials, to group online dictionary and encyclopedia sites deemed
appropriate for elementary school students
Professional Development, to group training sites and other resources that
employees are encouraged to use to build their skills
Use the Policy Management > Filter Components > Edit Categories > Add
Category page to add custom categories to any parent category. You can create up to
100 custom categories.
1. Enter a unique, descriptive Category name. The name cannot include any of the
following characters:
* < > { } ~ ! $ % & @ # . " | \ & + = ? / ; : ,
2. Enter a Description for the new category.
The character restrictions that apply to filter names also apply to descriptions,
with 2 exceptions: descriptions can include periods (.) and commas (,).
3. Select a parent category from the Add to list. By default, All Categories is
selected.
4. Enter the sites (URLs or IP addresses) that you want to add to this category. See
Recategorizing URLs, page 211, for more information.
You can also edit this list after creating the category.
5. Enter the keywords that you want to associate with this category. See Filtering
based on keyword, page 207, for more information.
You can also edit this list after creating the category.
Related topics:
Editing categories and their attributes, page 203
Filtering based on keyword, page 207
Redefining filtering for specific sites, page 209
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6. Define a default filtering Action to apply to this category in all existing category
filters. You can edit this action in individual filters later.
7. Enable any Advanced Filtering actions (keyword blocking, file type blocking, or
bandwidth blocking) that should be applied to this category in all existing
category filters.
8. When you are finished defining the new category, click OK to cache changes and
return to the Edit Categories page. Changes are not implemented until you click
Save All.
The new category is added to the Categories list and custom URL and keyword
information for the category is displayed.
Filtering based on keyword
Keywords are associated with categories, and then used to offer protection against
sites that have not explicitly been added to the Master Database or defined as a custom
URL. Three steps are necessary to enable keyword blocking:
1. Enable keyword blocking at a global level (see Configuring Websense filtering
settings, page 55).
2. Define keywords associated with a category (see Defining keywords, page 208).
3. Enable keyword blocking for the category in an active category filter (see Editing
a category filter, page 50).
When keywords have been defined and keyword blocking is enabled for a specific
category, Websense software blocks any site whose URL contains a keyword, and logs
the site as belonging to the specified category. The site is blocked even if other URLs
in the category are permitted.
Note
Category filters copied to a delegated administration role
set the filtering action to Permit for custom categories
created in the role. Delegated administrators should update
the copied category filters to set the desired action for their
role-specific custom categories.
Related topics:
Recategorizing URLs, page 211
Configuring Websense filtering settings, page 55
Creating a category filter, page 49
Editing a category filter, page 50
Working with categories, page 203
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For example, if the Sports category is permitted in an active category filter, but you
want to block access to basketball sites, you might associate the keyword “nba” with
Sports, and enable keyword blocking. This means that the following URLs are
blocked, and logged as belonging to the Sports category:
sports.espn.go.com/nba/
modernbakery.com
modernbabiesandchildren.com
fashionbar.com
Be cautious when defining keywords to avoid unintended overblocking.
When a request is blocked based on a keyword, this is indicated on the Websense
block page that the user receives.
Defining keywords
A keyword is a string of characters (like a word, phrase, or acronym) that might be
found in a URL. Assign keywords to a category, and then enable keyword blocking in
a category filter.
Use the Policy Management > Filter Components > Edit Categories > Add
Keywords page to associate keywords with categories. If you need to make changes
to a keyword definition, use the Edit Keywords page.
When you define keywords, be cautious to avoid unintended overblocking. You
might, for example, intend to use the keyword “sex” to block access adult sites, but
end up blocking search engine requests for words like sextuplets or City of Essex, and
sites like msexchange.org (Information Technology), vegasexperience.com (Travel),
and sci.esa.int/marsexpress (Educational Institutions).
Enter one keyword per line.
Important
If you are using Websense Web Security, avoid associating
keywords with any of the Extended Protection
subcategories. Keyword blocking is not enforced for these
categories.
Related topics:
Editing a category filter, page 50
Working with categories, page 203
Filtering based on keyword, page 207
Using regular expressions, page 226
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Do not include spaces in keywords. URL and CGI strings do not include spaces
between words.
Include a backslash (\) before special characters such as:
. , # ? * +
If you do not include the backslash, Websense software ignores the special
character.
If you are using Websense Web Security, avoid associating keywords with any of
the Extended Protection subcategories. Keyword blocking is not enforced for
these categories.
When you are finished adding or editing keywords, click OK to cache your changes
and return to the Edit Categories page. Changes are not implemented until you click
Save All.
In order for keyword blocking to be enforced, you must also:
1. Enable keyword blocking via the Settings> Filtering page (see Configuring
Websense filtering settings, page 55).
2. Enable keyword blocking in one or more active category filters (see Editing a
category filter, page 50).
Redefining filtering for specific sites
With custom URLs, you can:
Apply more precise filtering to sites that are not in the Websense Master Database.
By default, the action applied to the Miscellaneous\Uncategorized category is
used to filter these sites.
Filter sites differently than their Master Database category.
Websense software looks for custom URL definitions for a site before consulting the
Master Database, and therefore filters the site according to the category assigned to
the custom URL.
There are 2 types of custom URLs: unfiltered and recategorized.
Unfiltered URLs are permitted for all users not governed by the Block All
category filter or a limited access filter (see Defining unfiltered URLs, page 210).
Related topics:
Creating a custom category, page 206
Filtering based on keyword, page 207
Defining unfiltered URLs, page 210
Recategorizing URLs, page 211
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Recategorized URLs have been moved from their Master Database category to
another Websense-defined or custom category (see Recategorizing URLs, page
211).
A recategorized URL is not blocked by default. It is filtered according to the
action applied to its new category in each active category filter.
When a site is filtered according to its Master Database category, Websense software
matches the URL with its equivalent IP address. This is not the case for custom URLs.
To change the way a site is filtered, define both its URL and its IP address as a custom
URL.
If a site can be accessed via multiple URLs, define each URL that can be used to
access the site as a custom URL to ensure that the site is permitted or blocked as
intended.
If a site is moved to a new domain, and an HTTP redirect is used to send users to the
new URL, the new URL is not automatically filtered the same way as the redirecting
site. To make sure that the site is filtered appropriately at its new address, create a new
custom URL.
Defining unfiltered URLs
Use the Policy Management > Filter Components > Unfiltered URLs page to
define a list of sites that any user can access, except when governed by the Block All
category filter or a limited access filter.
The Permitted sites list in the right portion of the content pane lists the unfiltered
sites (URLs and IP addresses) and regular expressions that you have defined (see
Using regular expressions, page 226). Each site is associated with a category.
Related topics:
Working with categories, page 203
Redefining filtering for specific sites, page 209
Recategorizing URLs, page 211
Important
By default, when a site is added as an unfiltered URL,
Websense software permits the site automatically. No other
checking is performed.
This means that if an unfiltered URL site becomes infected
with malicious code, user requests for that site are still
permitted, regardless of the site’s Master Database or
Scanning categorization.
For instructions to change this behavior, see Prioritizing
Security Risk categorization, page 212.
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