The Study On Several Classes Of Multicast Routing Problems In Computer Networks

With the development of the technology of network, multicast communication plays an increasingly important role in many real-time services, such as multimedia meeting, distance education, data distribution and so on. Multicasting is an important transmission means for multimedia applications, which transmits the information from a source node to other destinations (but not all nodes). The key to solve multicast routing problem is to fix the multicast routing, and the common way to do it is to establish a multicast tree.At present, single-target multicast routing and multi-objective multicast routing are also one of the hotspots to research routing problems. In this thesis, we focus on designing some effective algorithms for several classes of multicast routing problems. The main works are as follows:â'ˆSummarize the shortest path tree problem, the Steiner tree problem and the traditional algorithms about them because the shortest path tree and the Steiner tree are two typical multicast trees.â'‰According to the research of the conventional algorithms about the shortest path problem, an improved algorithm based on the weight matrix method for the shortest path is presented. Simulation results show that this algorithm can improve efficiency and find the shortest path in the network more directly, compared with the weight matrix method for the problem. Especially when a lot of nodes in the network become the destinations, this algorithm is a more forthright and effective method to find the shortest path from a source node to other destinations.â'ŠThe minimal spanning tree problem is addressed which is the special example of the best Steiner tree problem. An improved algorithm based on the weight matrix method for the minimal spanning tree is proposed, and its complexity is analyzed. Simulation results show that both this algorithm is capable of reducing superfluous calculation and improving efficiency, and superior to the weight matrix method for the problem.â'‹The thesis also researches and argues about the two-target multicast routing problem, and it puts forth a new algorithm about the two-target shortest path and the two-target shortest path tree respectively. The algorithms are proved by the examples are very effective and superior.