Based Linux System Multicast Applications

The target of this thesis is to provide a cheap and fine but effective multicast router, which is realized by researching the multicast protocols and coding on the Linux system, for the widely used multicast applications. It can also serve the increasing multicast services as well as the small and middle multicast services provider. To realize it, we research the existed multicast technologies and the undergoing development, and summarize their advantages of flexibility, reliable and cheap to design the protocol schemes and coding the procedure on the Linux system.This thesis firstly introduces the basic knowledge and principals briefly, and then explains the concepts of SPT, RPT and RPF which are unique to multicast. Then we discuss the protocols IGMP and PIM-SM, which are essential to realize multicast. Before discussing PIM-SM, we analyze and compare all kinds of multicast routing protocol, DVMRP, MOSPF, PIM-DM, CBT and PIM-SM to conclude the reason why we choose PIM-SM. After the comparison we illustrate the detail of the two protocols to help us realize the routing program accurately in the following chapter. After the discussing, we code on the Fedora Core 7 system to realize the IGMP and PIM-SM according to the research of former results and our summary of their advantages. We also illustrate the procedure of processing the protocol datum. After the realization, we use some Linux systems, which have been installed our program, to establish a testing environment to debug and test the accuracy of our multicast router. Finally the program passed the test and we come up to our expectation. The following chapter we introduce a security scheme for multicast applications. We introduce the infrastructure and each part separately. In the end, we summarize the work we have done and we need to do in the future.