You can configure individual fields in a traffic profile as variables. Traffic profile variables are evaluated when the policy executes the traffic profile that contains it. Traffic profile variables let you reuse traffic profiles for a range of situations without having to create additional profiles that might differ only in a few ways, or add traffic profiles to policy tables. Traffic profile variables are available for the following profile types:
- ADC Rule
- Diameter QoS
- PCC Profile
- PCC Rule
To use variables in a traffic profile, select the Enable Dynamic Override check box when creating or editing the profile. This displays fields in which you can enter variables for one or more profile values.
A variable supersedes any defined static value. If a variable is not available when it is evaluated, the static value is used and the existing traffic profiles continue to work as before. If neither a variable nor a static value is available, the parameter is ignored and the associated AVP is not included under the Charging-Rule-Definition AVP.
You can include the following classes of traffic profile variables:
- Substitution variables
- Predefined variables available during policy rule execution within an MPE device to allow for substitution of these variables for contextual information. For example, {Time} is replaced by the time value when a policy rule that references it is evaluated.
- Policy table variables
- Variables that reference a policy table column.
- Policy evaluation variables
- Variables that exist only for the lifetime of a policy evaluation cycle (that is, the process of evaluating all the policies for a single request or context).
- Session state variables
- State variables that have a value that is saved only while the session they are associated with is valid. After the session is terminated, session state variables no longer have a value and are no longer available for use in policies.
- Subscriber local state variables
- State variables that exist locally on the MPE device and have a value while the associated subscriber has at least one session on that device. After the last session is terminated, subscriber local state variables no longer have a value and are no longer available for use in policies.
- Subscriber remote state variables
- State variables that exist remotely in an SPR database and have a value while the associated subscriber exists in that database. Using subscriber remote state variables requires that an SPR or HSS database is configured and capable of storing these variables.
See Example Traffic Profile Variables for examples of traffic profile variables.