The Voip Technology In The Network Monitoring System

This dissertation has discussed the R&D process of a broadcasting system based on network for fire fighting. This broadcasting system is based on the LAN, and it has used the technology of VOIP. It has implemented the network speech communication by packet switching, and it has removed the shortcoming of the traditional broadcasting system which is based on circuit. It is easy to extend and the communication distance is unlimited. This network fire fighting broadcasting system can use existing network resource availably and implement the speech communication in the networking buildings in the garden area. It can implement the broadcasting to various buildings at the same time, and it also can implement the broadcasting with multichannel different speech data. The speech data may be the audio files or the microphone input speech. This network fire fighting broadcasting system is intellectualized, it has implemented the remote control and watch.This network fire fighting broadcasting software system spans two operating systems. The server software is based on Windows2000 operating system and the client software is based on WinCE embedded operating system. First of all, the dissertation has introduced VOIP system framework, the application area, the basic principle and the major technology. Then the needs and feasibility of the network fire fighting broadcasting system have been analysed. After analyzing the old equipments and the new equipments, the total solution of the network fire fighting broadcasting system were made out. In course of the system designing, the traffic module and the control module were discussed by the modular concept. In detailing the traffic module, the G.726 voice compression algorithm of CCITT have been analysed and researched. The algorithm has been simplified based on the actual engineering and has been implemented by the simplified form in this project finally. This has improved the voice compression. There are the input and output of the traffic module, the buffer designing, the thread of sending and receiving designing and the data communication in this dissertation. The related performance has been quantified. In this system, the control module includes two parts. One is the module of controlling the client software and the other is the module of controlling the operating board. The system has implemented the...