The Design And Realization Of VoIP Communication System Based On ENUM

VoIP(Voice over Internet Protocol, the IP network telephone) means to transmit voice packets by Internet Protocol over Internet. In recent years, as the integration of three nets, people expect to use Internet to transmit voice. So VoIP is proposed and develops quickly, and the technology becomes the key point of the voice transmission over internet. For VoIP can take use of internet, improve the bandwith utilization ratio, and its extensive application can promote the development of multimedia application, to research VoIP and to promote the application of VoIP technology is very important to the development of internet communication.In General, VoIP is composed of two parts: media and signaling. Media refers to the voice data which is preprocessed, such as compression and coding, for transmission. Signaling is used to control the transmission of media. Signaling technology is the key technology of VoIP. SIP is an application layer signaling protocol which is used to initiate or terminate a session. It is very simple, easy to extend and flexible.At present, VoIP has three communication modes: PC to PC, PC to Phone, and Phone to Phone. ENUM can realize the fourth mode, Phone to PC. ENUM is used to translate the address between PSTN and Internt. It's very significant to promote the integration of public switch telephone network and internet.This thesis gives an overall structure of VoIP communication system and the realization method, researches the composition and the basic work processes of SIP, analyses the basic principle of ENUM and its application in this system, realizes the PC to PC communication mode, discusses the deficiencies of the system and proposes the possible improvement methods.