Server Side Design And Implementation Of VoIP System Net-to-Net Part

IP-based network has become an irresistible trend. With the evolution of networks and new technologies developing, VoIP will be more and more into businesses and households, VoIP is a platform for the evolution of multimedia services, is the integrated infrastructure of voice, video and data. Although the circuit-switched from the beginning is designed to transmit voice and completed well, but it not suitable for new demands of multimedia communications. IP as an attractive choice for voice transmission has many reasons. Since the IP has more open architecture than circuit-switched system and IP standard more open and flexible than circuit-switched system, these allow providers to offer new features faster, better define the services provided, complete the development and deployment of new features in a shorter period of time. All these mean greater competition, greater flexibility of network operators and resulted in lower equipment costs. Moreover, integration of voice and data, lower bandwidth requirements, the broad availability of IP all are the advantages of voice transmission with IP. In this paper, the subject comes from Secomity VoIP System development project, main contents is net-to-net part development of the VoIP system . Based on original net-to-phone system of Secomity companies,designed and developed server-side to support VoIP systems net-to-net part.This paper analyzed the VoIP system Communication Theory, VoIP related technologies and standards. Based on the Secomity company original system architecture,designed and implemented server-side of VoIP system, which include UAS (User Registration Server) and CCS (Call Control Server). Development based on LAMP environment and C programming in LINUX. UAS is responsible for system authentication, authorization, call control server management and user management. CCS is responsible for recording the user call state and call duration, setting a interfaface for possible billing demand. System client and server work on browser/server mode, SIP used as signal protocol. The realization of key technologies of server side are discussed such as heart beating and private netweok traversing...