Research On Multicast Protocols Based On Ethernet And Their Applications In Net Video Monitor System

With the fast development of net video monitor system, it has been applied to many fields in recent years. The video monitor system, which is an important part of intelligent building, still adopts the traditional video monitor system, and hardly adopts net video monitor system. When people's demand for integration level in intelligent building increases gradually, the traditional video monitor system can not meet the demand of integration in the intelligent building. So it is necessary to apply the net video monitor system to intelligent building.The first chapter and the second chapter of this thesis describe the establishment of the net video monitor system based on LAN for trial in court according to the requirement of Hefei court firstly. The net video monitor system includes hardware structure and software structure. Besides, it describes the plan of integrating the net video monitor system into IBMS in court. Finally, it puts forward two problems which are very important for the net video monitor system for trial in court: one is that when many people watch the spot of monitor system at the same time, a mass of video and audio data will wastes plentiful net bandwidth;the other is that when the multicast message is transmitted to link layer switch, the link layer switch will broadcasts the multicast message.The rest of this thesis aims at the two problems mentioned. It introduces the IGMP protocol firstly. And then, it compares and studies three link layer multicast protocols: IGMP snooping, GMRP and CGMP. Besides, it introduces the application of IP multicast technology and IGMP snooping protocol to the net video monitor system for trial in court and discusses the implement of IP multicast technology in WinSock and the implement plan for IGMP snooping protocol. Finally, we test the network performance in the net video monitor system with IP multicast technology and IGMP snooping protocol. The results of test indicates that adopting IP multicast technology and link layer multicast protocol can improve the network performance effectively for net video monitor system.