Diameter Credit Control Application of Gx Interface

DCCA (Diameter Credit Control Application)

The current accounting models specified in the Radius Accounting and Diameter base are not sufficient for real-time credit-control, where credit-worthiness is to be determined prior to service initiation. 

In order to support real-time credit-control, a new type of server is needed in the AAA infrastructure: Diameter credit-control server.  The Diameter credit-control server is the entity responsible for credit authorization for prepaid subscribers

Message for Credit-Control

CCR/CCA (Credit-Control Request / Answer)

The Credit-Control-Request message (CCR) is indicated by the command-code field being set to 272 and the R bit being set in the Command Flags field. It is used between the PCEF and the PCRF to request credit authorization for a given service.

The Credit-Control-Answer message (CCA) is indicated by the command-code field being set to 272 and the R bit being cleared in the Command Flags field. It is used between the PCRF and the PCEF to acknowledge a Credit-Control-Request command