Google Message Security for Google Apps Administration Guide - Manual (Page 200)

200 Message Security for Google Apps Administration Guide
Content Manager Features
You can use Content Manager to filter both inbound and outbound email
messages. To filter messages, you can create custom content filters and set up
content compliance policies.
Custom Content Filters
A custom content filter comprises up to three content rules and a message
disposition. Each rule contains a word or phrase that you specify. Or, a rule can
contain a text pattern, called a regular expression, rather than specific text.
Content Manager scans messages for content that matches one or more rules in
the filter. If a message contains a content match, Content Manager takes action
on the message according to the message disposition for the filter.
For instructions on creating a content filter, see “Create or Edit a Content Manager
Filter” on page 209.
Compliance Policies
A compliance policy comprises a lexicon—a predefined set of words, phrases,
and text patterns—and a message disposition. Content Manager scans
messages for content that matches content in the lexicon. If a message contains a
match, Content Manager takes action on the message according to the message
disposition. Currently, Content Manager includes compliance policies for social
security numbers and credit card numbers. Use these policies to help protect
personal information and enforce compliance at your company.
Important: The lexicons are designed to provide a high level of filtering accuracy.
However, because patterns for social security and credit card numbers are highly
variable, these lexicons may not capture all messages that contain social security
or credit card numbers. In addition, these lexicons may capture messages that
contain numerical patterns that are not social security or credit card numbers.
For instructions on setting up a compliance policy, see “Set Up a Compliance
Policy” on page 214.
Regular Expressions
Instead of creating simple content filters that can find only single words or
phrases, you can use regular expressions to create more efficient or sophisticated
content filters. A regular expression, also called a regex, is a method for matching
text with patterns. For example, a regular expression can describe the pattern of a
telephone number, an email address, a URL, or your company's employee
identification numbers. It can also describe a list of words.
For more information about using regular expressions, see “About Using Regular
Expressions” on page 218.