Design To The Softswitch Network And Implementation To Its Security Mechanism Of Kunming Telecom

Softswitch adopts the advanced system structure of PSTN, and carries more information including voice, data and the multimedia stream with the IP packet in the IP network, is a hot topic concerned and discussed by communication industry recently.Softswitch network can not only inherits the existing voice service of PSTN completely, but also provides many various and particular services such as data, multimedia and so on. It has the benefits of lower cost and newer technology, which is the developing trend of next generation network.This thesis is exactly directed against problem described above, regarding the current situation of KM telecom PSTN as the main researching object. Do research, planning, and designing on Softswitch project of KunMing Telecom Corporation.The main content is:This paper introduces the project background of Kunming Telecom PSTN network evolving to Softswitch network,even involves the related scope of this topic and the recent goal of the network development, and point out that Softswitch is the developing trend of PSTN. Then describe problems such as traffic , signal and resource planning of Softswitch and so on.With the development of Softswitch technology, various multimedia services based on IP networks are popularized rapidly. Signaling control protocol is absolutely necessary for the management of multimedia session. Session Initiation Protocol (SIP) is an application-layer signaling protocol used to establish , modify , and terminate multimedia sessions.Compared with H.323, SIP is more tightly integrated with Internet protocol and has a lot of advantages.Now sip is widely used and attracting more and more attention.SIP system often works in an open and complex network envirement, which leads to various kinds of security threats to SIP elements and message.It is an important problem to solve that proper security mechanisms have to be designed to protect SIP networks.The analysis of the function, structure and work flow of SIP is given according to RFC3261, with emphasis on the layered protocol structure and key elements such as transaction, dialog and so on.Then the security problems by SIP networks are discussed. Some security mechanisms are chosen to establish an integrated SIP security framework.The TLS, S/MIME, HTTP authentication mechanisms and their application in SIP system are studied in detail.Specially, a solution is designed for the deployment of SIP in large scale networds, which integrates SIP networds and AAA system with the help of EAP and HTTP EAP authentication.