Sip-based Network Integration Of Key Technologies

SIP-based next generation network (NGN), be able to seamlessly integrate 3G, WLAN, PSTN, Internet and other types of networks, SIP will dominate the NGN network. SIP-based network integration platform provides SIP-based network services, such as setting up SIP connection, user location, text transmission, authentication, and so on.These services can allow service providers to customize and provide a combination of SIP-based Services, and to further develop new SIP services based on this platform.The platform in accordance with the RFC3261 standard, based on the JSIP implement the SIP protocol stack, including: encoding layer, transport layer, transaction layer. JSIP is a standard JAVA interface of SIP, which use Listener/ Provider event model and can be used by high-level application entities.And then, the platform implement the SIP network server on this basic protocol stack, including: SIP proxy server, SIP redirect server, authentication server, configuration server, and register server.SIP proxy server is responsible for setting up the SIP connection and transmiting text informations with the SIP message. It is the entrance of SIP message, and the core of the whole SIP network server. SIP register server is responsible for handing customer register message, and to register and update the location information. Authentication server is responsible for the certification of the customer's identity which is the intiator of a request by using MD5 Authentication algorithm. Only through the certification, customer can send a massage. Configuration server is responsible for initialize configuration of SIP proxy server, authentication server and register server according to the configuration files. Redirect server is responsible for dealing with message routing information, and is the core element of message forwarding. It decides the next hop address according to the location infromations from the register server when the next hop address cann't be decided by the request. At implementation, The platform expand the register approach of the RFC3261 standard, so that the redirect server can use richer informations of location, and enhance the message routing capability and efficiency of SIP proxy server.All the above are the basic services of SIP-based network system. Finally, the platform has been tested, including: Call Succeed Probability, Registration Succeed Probability, Call Holding Ability, Intercommunication Ability and Calls Per Second testing.The platform provides a basic architecture for SIP-based network environment, developers can continue to fit the architecture, and develop more SIP Service.