When the Rule Type selected is Modify URL the following describes the options available.

Rule Name

This is for a textbox to enter the name of the rule.

Match String

This is a textbox to enter the pattern that is to be matched.

Modified URL

This is a textbox to enter the URL that is to be modified.

Perform If Flag Set

Only execute this rule if the specified flag is set.

The flag is set by a different rule. For a more detailed explanation of flags please refer to the Content Matching section.

Perform If Flag is NOT Set

Only try to execute this rule if the specified flag is not set.