CHAPTER 3

Configuring Advanced Expressions:

Getting Started

Advanced policies evaluate data on the basis of information that you supply in advanced expressions. An advanced expression analyzes data elements (for example, HTTP headers, source IP addresses, the NetScaler system time, and POST body data).

To create an advanced expression, you select a prefix that identifies a piece of data that you want to analyze, and then you specify an operation to perform on the data. For example, an operation can match a piece of data with a text string that you specify, or it can transform a text string into an HTTP header. Other operations match a returned string with a set of strings or a string pattern. You configure compound expressions by specifying Boolean and arithmetic operators, and by using parentheses to control the order of evaluation. You can also include classic expressions in an advanced expression.

Advanced expressions are typically part of a policy, and you can assign names to frequently used expressions so that you do not have to enter the full expression repeatedly in multiple policies. But for some features, you configure advanced expressions outside the context of a policy.

In This Chapter

Expression Characteristics

Basic Elements of an Advanced Expression

Compound Advanced Expressions

Classic Expressions in Advanced Expressions

Configuring Advanced Expressions in a Policy

Configuring Named Advanced Expressions

Configuring Advanced Expressions Outside the Context of a Policy

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Citrix Systems 9.2 manual Configuring Advanced Expressions Getting Started