Create customized expressions if none of
the predefined expressions meet your requirements.
Expressions are a powerful string-matching tool. Ensure that
you are comfortable with expression syntax before creating expressions.
Poorly written expressions can dramatically impact performance.
When creating expressions:
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Refer to the predefined expressions for guidance on how
to define valid expressions. For example, if you are creating an
expression that includes a date, you can refer to the expressions
prefixed with "Date".
-
Note that
IMSVA follows the expression formats defined in
Perl Compatible Regular
Expressions (PCRE). For more information on PCRE, visit the following
website:
-
Start with simple expressions. Modify the expressions if
they are causing false alarms or fine tune them to improve detections.
Specify criteria when creating expressions. An expression must meet specified criteria
before
IMSVA subjects it to a DLP policy. For details
about the different criteria options, see
Criteria for Customized Expression.
