Research And Implementation Of The Secure Multicast Transmission

With the widespread popularity of the Internet and the gradual maturity of multimedia technology, more and more group applications appear in our real-life, such as stock information distribution, video conferencing, pay-TV and mirror synchronization, etc. In general, unicast is appropriate to the network with only a few clients, broadcast is appropriate to the one with a large number of users, and multicast is to the group application which has uncertain amount of clients.Multicast is a group communication model for multi-point transmission and multi-party collaboration, which means that the sender transmits only one copy of data, and the multicast router makes certain copies in accordance with the required number of the receivers. Multicast has the advantage of reducing both the calculation load of the sender and the number of copies of data online, and thus it makes an efficient use of network resources. However, it is the openness of multicast that has led to the security issue which is hindering the development of IP multicast model. T.Hardjono and B.Cain elaborate the multicast security issue in three aspects: first, the protection of the multicast tree; second, the encryption measures to ensure the end-to-end data communication; and third, the access control of members. This thesis is to design a Multicast Security Protocol to provide a solution to the first aspect.MPLS (Multi-protocol Label Switching) is a newly emerging routing technology, which absorbs the idea of ATM's exchanging virtual circuit number, integrates Layer 2's switching and Layer3's routing technology, and adds an connection-oriented property to the connectionless-oriented IP network. MPLS adopts traditional IP routing rules, but through labels will routing and packet forwarding be separate, which allows to promote the evolution of routing technology by label distribution strategies and forwarding methods correction in MPLS network. Furthermore, the packet forwarding of MPLS network, based on fixed-length label, simplifies the forwarding mechanism and thus improves the forwarding efficiency. Given MPLS Traffic Engineering's and VPN technology's excellent perform in the current IP network, MPLS has increasingly become an significant standard to expand the size of IP network. IP multicast and MPLS are two complementary technologies. MPLS multicast network has the ability of making rapid and efficient packet transmission, and also it offers IP network several new management and operation tools, ensuring the optimum of the use of network resources.This thesis shows a design based on the combination of these two technologies. First of all, it gives an overview of MPLS principle and related signaling protocols, and make simple analysis of IP multicast technology and the existing multicast protocol. Then it carries out an in-depth analysis of the enforceability of both MPLS multicast program and secure multicast protocol, establishing the overall design of MPLS multicast system. After that, it performs an detailed design and the ultimate implementation of the two core modules of the project——secure multicast protocol processing module based on CR-LDP and MPLS transmission module. Finally, the test shows that MPLS multicast system is able to meet the group clients'various requests, with a better stability as well.