You can configure NetScaler Gateway to run the post-authentication policy at specified intervals. For example, you configured a client security policy and want it to run on the user device every 10 minutes. You can configure this frequency by creating a custom expression within the policy.
You can set the frequency (in minutes) when you configure the client security policy by following the procedure Configuring a Post-Authentication Policy. The following figure shows where you can enter a frequency value in the Add Expression dialog box.