The Design And Construction Of Softswitch System For G.D. CNC

Development of telecommunication trade,the integrative communication capacity of the telecommunication network increases obviously. More multiplex services are demanded.On one hand, the existing SPs(service provider) need to avoid function innovation slowing down and get rid of the less competitive predicament. Building up and developing of new SPs also need to seek a new way to grow up and develop technology. On the other hand, the national business of the immobile telephones turn high-speed increase into slow development at present. The business of speech sounds are continuously subject to the extrusions of local mobilezations and long-distance IP calls.The value of consumers is always declining. In the open market environment as our country intered WTO, SPs seek a new technology which can decrease Capex and Opex hardly. Achieving technical innovation, function innovation and management innovation is a necessary way to gain market by building up the next generation network(NGN) that is of high level and basaed on the open netwok platform. Based on this background,the next generation spoken network using the softswitch technology is coming into being at the opportune historic moment.The softswitch technology breaks the close traditional exchange structure.It adopts the combined pattern, open interfaces and generally used agreements to establish a open nad distributed system structure for more customers'application.The substance of softswitch is to turn traditional switch matrix to the IP network.The network is open,easy and cheap.It makes use of superiorities of the network to exchange speech sounds.The article bases on the softswith experimental network project of the GuangDong CNC. It has researched and solved some problems which are met in the period of network establishment utilizing the softswitch faclities of the manufactures. The problems include selecting of softswitch protocol, selecting of network structure, carrier network, encapsulating encode, QOS, accesss modes.We choose one from several plans by demonstrating and evaluating with regard to every technological problem.This softswitch experimental network uses the plane routing structure and the G.711 encapsulating code. It carries VOIP stream by IP network.It uses MPLS-VPN at the core layer. To achieves QOS, it diffluences and redundans in convergence layer. It provides flexibility by using different access mode for different subscribe environment.