Policies are used to configure various Citrix NetScaler Application Switch features. For example, the parameters for compressing content are defined in a compression policy.

The features that use policies are:

• Load Balancing
• Content Switching
• Content Filtering
• AppCompress
• Cache Redirection
• SSL VPN
• Priority Queuing
• DoS Protection
• Sure Connect

Policy expressions are applied to content that enters the switch. Expressions are shared among features, but actions are feature-specific. For example, you can create an expression to identify .pdf files being sent through the system. You can then create a compression policy that uses this expression to compress those files. The Policy Engine (PE) refers to the architecture in the Citrix NetScaler Application Switch for versions up to 8.x. The architecture for Policy Engine and the manner in which it operates is presented in this Deployment Guide.  Did you know that each feature in the Citrix NetScaler Application Switch is processed in a certain order, and the Policy Engine (PE) applies policy according to that order.  That order is represented in this diagram and discussed in the Deployment Guide for Policy Engine (PE).

Watch this Policy Engine Tip:

Tap into the power of AppExpert!