Study On QoS Multicast Routing Problem Based On Genetic Algorithm

As the demands for quality of service (QoS) by multi-service in Internet are rapidly increasing, effective and efficient QoS support has becoming more and more important. The routing technology is one of the key roles to guarantee QoS, so the routing mechanism and QoS must be become together.Now, researches on multicast routing algorithm mainly focus on multicasting algorithm without constraints and delay-constrained multicast routing, and also use heuristic algorithm. The research of this thesis focuses on how we can apply genetic algorithm to QoS multicast routing problems. Because it has so many advantages, such as concurrent searching and colony optimize, as to provide us some new methods to solve the QoS multicast routing problems. Four typical problems are discussed in the thesis. So the thesis has four parts:The first part is introduction. We summarize on multicast communications in computer networks. We present the background of multicast, special feature and technology. We also narrate the content on QoS multicast, the present research situation, multicast routing agreement and using.The second part is the foudamental part of the research. We give an account of QoS metric, graph model and the existing problem, and the research of present on multicast routing algorithm.The third part recommend the development history of genetic algorithm, and including characteristic, advantage and disadvantage. We also give the basic step, hybrid genetic algorithm, some details have yet to be discussed about soluting the constraint QoS with genetic algorithm.The fourth part is the emphasis of the research. The present research hotsports that apply genetic algorithm to QoS multicast routing are mainly discussed. We have studied four important multicast routing, problems with QoS parameter constraints such as time-delay constraint, time-delay variation constraint, degree constraints and some QoS parameter constraint. According to the character of QoS multicast routing and optimize character of genetic algorithm, a new approach based on hybrid genetic algorithm is proposed to solve time-delay parameter constraint problem and another hybrid genetic algorithm be used on some QoS multicast routing problem.