Based On The Tv Broadcast System In The Network Layer Multicast

Since the 90' s in 20 centuries, along with the universality of the Internet and technical development in IT, the correspondence method of telegram, E-mail etc. has already been not only contented by people, more and more audio, video business are walking into the people's work and lifes through the network.At the traditional unicast mode, these businesses take up a great deal of bandwidth, consuming the resources of the network, turning worse the degree of the network congestion.If this kind of flow can be reduced, it will promote the function of the network greatly. Exactly according to this kind of consideration, the IP multicast appears.On the foundation of thorough research in the traditional IP multicast technique and multicast protocols architecture, this thesis studies the PIM-SM protocol, mainly Analyzes the disadvantage of ASM model from the aspects of ISP, ASM model and customers' benefits etc. This thesis detailedly introduces the work process, the protocols architecture and the advantage of the model of SSM, compares the characteristics of ASM model and SSM model, inquiries into the key problems for IP network stream medium transport. At last this thesis realizes SSM model of television live system based on PIM- SM protocol.This system considers fully the request of the safety and QoS, by making use of the winsock2 programming and the source authentication technique, guarantees the safety of the system on the certain degree. To the QoS, this system makes use of the wreath form buffer to save the data, after a certain time of delay, hands over for clients to replay and improves the quantity of display.This system be specially applicable to numerous receivers' situation, satisfies the request of the television broadcast live the system, increases the safety of the system. Makeing use of the technique of DirectShow,it realizes the display for high quantity of the stream medium. Tests verifies the system's usability and safety.