Control Plane Operations for Services Control Gateway
The following processes occur in a sequenced way on the control plane of a router that functions as a TDF:
The subscriber edge network element sends accounting start messages during subscriber activation.
SDG steers the accounting request to a session Packet Forwarding Engine. A subscriber record is created using the IP address and VRF parameters.
Policies are downloaded from the PCRF using GX interface.
If online charging is enabled, quota information is retrieved from the OCS.
Subscriber and associated policy rules are programmed on the service Packet Forwarding Engine.
Subscriber routes are programmed on the PGW-facing Packet Forwarding Engine to steer traffic to TDF service Packet Forwarding Engine.
Subscriber and associated policy rules are programmed on an anchor Packet Forwarding Engine.
SDG responds back to subscriber edge network element with an Accounting-Start acknowledgment.