A system expression specifies the conditions under which the policy is enforced. For example, expressions in a preauthentication policy are enforced while a user is logging on. Expressions in a session policy are evaluated and enforced after the user is authenticated and logged on to NetScaler Gateway.
Expressions on NetScaler Gateway include:
NetScaler Gateway can also be used as a Citrix NetScaler appliance. Some expressions on the appliance are more applicable to NetScaler. General and network-based expressions are used commonly with NetScaler and are not generally used with NetScaler Gateway. Client security expressions are used on NetScaler Gateway to determine that the correct items are installed on the user device.
Expressions are a component of a policy. An expression represents a single condition that is evaluated against a request or a response. You can create a simple expression security string to check for conditions, such as: