The Research And Implementation Of Offline Charging Collection Function In Ip Multimedia Subsystem

To adapt to IP multimedia applications development trend, the IMS (IP Multimedia Subsystem) is introduced, which is a critical component of the 3G mobile communication core network, and which is to achieve all the best option for the network integration.The Offline Charging Collection Function can make a variety of data into a unified standard format and simplify the process of the billing system. The Offline Charging Collection Function is the interface between the billing system and IMS nodes. The performance of the Offline Charging Collection Function has a direct impact on the function of the whole billing system.How to ensure the safety and reliability of the accounting data is the key issue of the CCF. To solve this issue, this paper develops a high available CCF by using the high-availability technology. In this paper, the primary work includes:1. Studying IMS specifications from 3GPP and IETF, summarizing the distinction between the two charging mechanism, refining the demand of the CCF from the relevant standards.2. On the basis of analyzing Diameter protocol, I give out the Diameter peer-to-peer model.3. Studying the availability of CCF, proving the binary redundancy is the most efficient in high-availability cluster technology, and demonstrating the reason of using the active and hot-standby approach for CCF system.4. Studying the availability of CCF, proving the binary redundancy is the most efficient in high-availability cluster technology, and demonstrating the reason of using the active and hot-standby approach for CCF system.5. Testing the CCF system in the real IMS network.