Design And Implementation Of IMS CSCF Cluster Software

IP Multimedia Subsystem(IMS)is a new form of multimedia service,which not only can solve the fixed network and mobile network integration,but also can bring people more colorful multimedia business experience,so that people's lives more beautiful.As the most important call control entity in IMS-CSCF(Call Session Control Function),the main function is to provide session call service.CSCF can be subdivided into Proxy CSCF(P-CSCF)network element,Interrogating CSCF(I-CSCF)network element and Serving CSCF(S-CSCF)network element.These three kinds of CSCF elements are the core elements of communication,which are the key factors related to the quality of communication.Therefore,the reliability,scalability and efficiency of these three kinds of network elements are very high.But the IMS system in a separate CSCF network element can not meet the above needs.Based on the above requirements,in this paper,cluster technology is used to make the independent CSCF nodes into CSCF clusters by using cluster technology to meet the scalability,reliability and operation efficiency of call session control.At the same time,this paper designs the CSCF cluster software according to the IMS communication situation,and discusses its implementation principle,load balancing strategy,backup strategy,software design and implementation and so on.The main contents of this paper are as follows:1?Two methods of CSCF cluster implementation are proposed-centralized communication mode and distributed communication mode,the two methods are analyzed and compared deeply.Finally,one of the implementation methods is chosen as the design scheme of CSCF cluster.2?Based on the research of the existing mainstream load balancing technology and the functions and communication flow provided by P-CSCF,I-CSCF and S-CSCF,the load balancing strategy for CSCF cluster is designed.3?The backup strategy is studied,and the backup strategy for CSCF cluster is designed based on the investigation of the existing mainstream backup technology,and the combination of practicality and development difficulty.4?The CSCF cluster software is designed,including the design of cluster control software and the design of cluster agent software.At the same time,it should be applied to P-CSCF cluster,I-CSCF cluster and S-CSCF cluster in software design,so the software architecture,interface and protocol are studied deeply.On this basis,a set of software system is designed and implemented for these three kinds of CSCF clusters.In this paper,the test environment is used to test the function and performance of the software system.The test results are analyzed,and the CSCF cluster software is verified from the two aspects of function and performance to achieve the predetermined design goal.