Understanding Selection of Policy-Control Properties for an IP-based TDF Subscriber
As part of the traffic detection function (TDF) subscriber session creation, the subscriber is assigned a policy and charging enforcement function (PCEF) profile, which specifies how policy and charging control (PCC) rules are defined on the TDF.
If every IP-based subscriber assigned to a TDF domain can share the same PCEF profile, then the PCEF profile can be specified within the TDF domain, under the [edit unified-edge gateways tdf gateway-name domains] hierarchy level. (For IFL-based subscribers, the PCEF profile must be specified within the TDF domain.)
If all of the IP-based subscribers assigned to the same TDF domain cannot share the same PCEF profile, the TDF domain does not specify a PCEF profile, and the PCEF profile selection must be configured under the [edit unified-edge gateways tdf gateway-name domain-selection term] hierarchy level. The domain-selection term consists of a from and a then statement.
The from statement identifies the match conditions for the subscriber. This includes the RADIUS client (GGSN, PGW, or BNG) that is sending the accounting start request for the subscriber and the values for particular AVPs in the message.
The then statement identifies the PCEF profile to assign to the subscriber. The then statement can also include the name of the TDF domain to assign to the subscriber. If the then statement only includes the PCEF profile, then another domain-selection term must assign a TDF domain to the subscriber.
When both a PCEF profile and a TDF domain are assigned to a subscriber in a domain-selection term statement, that PCEF profile is used even if the TDF domain specifies another PCEF profile.
Example: The TDF domain domain1 specifies a PCEF profile. The domain-selection term does not need to specify a PCEF profile.
Example: The TDF domain domain2 does not specify a PCEF profile. A domain-selection term must specify a PCEF profile. In this example, the PCEF profile is specified in the same term as the TDF domain.
Example: The TDF domain domain2 does not specify a PCEF profile. A domain-selection term must specify a PCEF profile. In this example, only the first term selects the TDF domain, so other terms must be added to select the PCEF profile.