SIP Multimedia Core Control Platform

With the rapid development of the Internet and the technology of telecommunication, the IP-based applications using SIP (Session Initiation Protocol) protocol has been developed into the concept of SIP multimedia system. Comparing with the prosperity of SIP multimedia services, the way of privilege management and access control are lagged behind. Thus the lag resulted in the higher operating costs, lower security and efficiency.In order to solve the problem mentioned above, SIP Multimedia Core Control Platform is proposed and designed, which melts the technologies of PKI/CA (Public Key Infrastructure/Certificate Authority), PMI (Privilege Management Infrastructure), RBAC (Role-based Access Control) and CPL (Call Process Language) into SIP multimedia system, offering an entire solution including user, Core Control Platform and SP, delivering SIP multimedia services and privilege management to users, achieving high security, availability, reliability and manageability.In the first part of the paper, SIP protocol related to SIP multimedia system is introduced. In technology background, there is also specification of PKI/CA, PMI, RBAC and CPL.In the second part of the paper, the architecture of SIP multimedia system is abstracted based on SIP basic session procedure, including Proxy procedure and Redirect procedure. With SMCCP is introduced in the architecure, the access control framework in SIP multimedia system is designed.In the third part of the paper, SMCCP is designed in detail. The design work is separated into three parts, architecture of SMCCP, SP module and core control module. After completing the design work, the subject analyzes the performance of SMCCP from three aspects: security, Certificate Chain and value-added points of the platform.In the fourth part of the paper, SMCCP is compared with IMS (IP Multimedia Subsystem) and MPLS VPN (Multiprotocol Label Switching Virtual Private Network), which are popular technologies in the field of telecommunications, to seek for affinity and expand business prospects.