Research Of VoIP Network And Implementation Of Gateway Based On SIP

VoIP (Voice over Internet Protocol) develops at very fast speed as a voice communication technology, which allows you to make telephone calls using a broadband Internet connection instead of an analog phone line. The service can make a communication connection between computers, traditional telephones and even GSM cell phones.The key technology of the development of VoIP is signaling technology. The most widely used protocol is H.323 and SIP. H.323 is the main stream in the VoIP equipment. But the protocol architecture of SIP is very simple and easy to realize; and SIP is convenient to expand .All these advantages show that SIP is fit for the future development of network.The paper carries an extensive discussion on the basic transmition theory of VoIP, VoIP system elements, key technology of VoIP and their application in the enterprise network; Having analyzed the syntax of SIP protocol, the entity, and the interaction conversation procedure between them, etc.The paper emphasizes on the VoIP operation principle of the network; compares several kinds of feasible realization schemes especially. Then according to the function needed to realize in the Gateway, provide the whole solution of IP gateway, including the hardware module block diagram, software module solution and realization of the gateway. In addition, software module solution and realization of the gateway is the point in this chapter. In this chapter, according to the software solution, the realization of SIP Stack and Endpoint module are discussed in detail; finally, the test solution of this gateway equipment in the LAN/WAN is provided; and several function of the gateway are tested, including registering on the SIP server and some basic conversation procedure. The result proves: this gateway runs well.