Design And Implementation Of IP Trunk Of IP PBX

In the past, the traditional telecommunications network and the Internet belong todifferent link networks, the traditional telecommunications network is just used totransmit analog phone and fax, the Internet is used to transmit digital data. In recentyears, the rapid development of DSP technology and computer telephony integrationtechnology, derived from a number of new products and services. with the successfulexperience of integration telephony and computer, thus wanted to blend the existinginternet, then had a internet telephone switching technology, in recent years, internettelephony is widely used in domestic and international long distance call.VoIP (Voice over Internet Protocol) is a technology which is main about IPtelephony, and introduced a value-added services, in a nutshell is the analog audiosignal digital, real-time transfer to the form of data packets in the IP data network.Thebiggest advantages of VoIP is widely using the Internet and global IP interconnectionenvironment,and give better services than the traditional.There are two mainprotocols, H.323protocol and SIP protocol, SIP protocol is more free and open togain more favor, this design also uses the SIP protocol. IP-PBX is an IP-based PBXvoice switching system, which is an implementation of VoIP technology. IP Trunk isthe bridge of IP PBX and the outside SIP server.This article uses the SIP protocol to build6processes of IP trunk call, the modulefunctions well to coordination with other modules to complete the call process.