Research On Multicast Core Selection And Its Application In Multicast Routing

IP Multicast and ALM (application level multicast) are hot topics in the recent research on Computer Network, as the one-to-many and many-to-many transfer applications arise. As the number of multicast groups and sources increases, the amount of states required at each multicast router grows. Core-based tree has great advantage on solving this problem. The core selection determines the formation of group-shared tree and has great influence on the multicast routing protocol. Current core selection algorithms are usually complex which needs detailed network information and long executive time. Thus, an important problem in Multicast is how to find the core in the domain efficiently. Detailed researches on multicast core selection are done in this thesis. The main works and creations are as the followings:1. The background and current research of IP multicast and ALM are analyzed, and the main problems of the core selection are pointed out.2. The concepts of IP multicast and ALM are introduced. The IP multicast protocols are classified and some commonly used ones are introduced, the advantages and disadvantages of core-based tree and source-based tree are analyzed respectively. Some ALM protocols are introduced and their core selection issues are analyzed.3. The concept of core selection is analyzed; the achievements of core selection research and some core selection algorithms are introduced. Core selection algorithms are classified and their complexities are analyzed.4. In order to solve the problems of current core selection algorithms, a new core selection algorithm-EDA (Eccentricity Decrease Algorithm) is proposed. The theory and the work process of EDA are described in detail and the performance is analyzed through modeling simulation.5. In order to solve the problems of IP multicast and ALM, a multicast protocol based on dual-core-DCRTP is proposed through analyzing the HMTP. The formation, maintenance and optimization of DCRTP's multicast tree and the formation, recovery of DCRTP's control ring are designed in detail. Modeling analysis proves that DCRTP reduces the influence of node failures on multicast tree.