The Testing Study Of VoIP System Based On Asterisk

To overcome the shortcoming of cable communication systems in coal mine and solve the problem of bad cooperation between monitoring, control and communication systems, we design the Digital Mine Integrated Wireless Area Net communication system in which the services of wireless voice communication, wireless video monitor and short message, equipment control, underground environment monitoring, emergency alarm are provided. Because of the advantages of the VoIP (Voice over Internet Protocol) technology, it is used to provide the service of the wireless voice communication.Asterisk is an open-source software package, and all the features of PBX can be run on that. It also can provide value-added services such as voice mail services,telephone conference. Asterisk supports both traditional analog telephone equipment and digital telephone equipment, and it also supports the VoIP voice system.IP02 is a 2-port IP-PBX, and it combines Asterisk with Linux system so that you can achieve all of the Asterisk features in a very small and low-power embedded board. Because of the advantages of IP02, it is chosen to build the VoIP system.In this thesis, we introduce the basic knowledge of VoIP technology; analyze both SIP and IAX protocol including the process of registration and call procedure. In this thesis, we design and implement the communication system in which the functions of wireless voice communication wireless video monitor and short message, equipment control, emergency alarm function are integrated.The author's major work is to realize the voice communication system, test the system functions in both campus and coal mine, give the conclusions and analyze the experimental results. In addition, three extended functions of call group, conference call and voice mail are implemented and the solution of providing communication between two universities via internet is proposed by using IP02 as a gateway.