Research On High-Performance Multicast Routing Algorithms Based On IP Networks

With the fast development of computer and network technology, the quality andperformance requirement for communication network is becoming more and morestrong, and a line increase is incurring in network resource requirement. Especially,all kinds of multimedia application, such as video-conferencing, IP telephone,distance education, collaborative computing, distributed database, are widely appliedin Internet, which leads to a great need in bandwidth resource and seriously evenleads to a congestion. Those applications have two common characteristics: firstly,there is a great deal of data to transfer and consume much bandwidth; secondly,source node communicates with destination nodes often by one-to-many ormany-to-many method. It is clear that multicast is the best communication method forthis kind of service.A fundamental issue in multicast communication is how to construct a simple,efficient, robust multicast tree by using multicast routing algorithm. In this paperhigh-performance multicast routing algorithms based on IP were researched in threedifferent aspects: reducing the cost of multicast tree to optimize the network resource,reducing the computing complexity to minimize the routing time, and highperformance in satisfying QoS. All the high-performance algorithms proposed in thepaper included a delay-constrained multicast routing algorithm for static networktopology, a multicast routing algorithm for dynamic destination members, and amulticast routing algorithm for mobile IP. In detail, it includes as follows:1) Firstly, the problem of multicast routing was defined and a survey of foreignand destinatic was discussed. Then technologies and methods of how to implementhigh-performance IP multicast routing algorithms were introduced. Three simulationmodels were designed, including simulatin environment based on static topology,simulation environment for dynamic membership, simulatin environment for mobileIP.2) A path node-driven idea was proposed following the destination-driven idea inchapter 3, which reduced the cost of multicast tree mainly by link shareness. Based onthe idea a low-cost multicast routing algorithm (LCSPT) was designed. Correctnessand performance of LCSPT were analyzed in theory. Experiments were simulated indifferent aspects. LCSPT algorithm not only produced a SPT correctly but also hadthe best optimization performance among all the SPT algorithms.3) The problem of delay-constrained multicast routing was discussed in chapter 4.A delay-constrained algorithm called Delay-Constrained MPH (DCMPH) waspresented to construct a Delay-Constrained Least-Cost (DCLC) multicast tree. By using the algorithm a computing destination node can join the multieast tree byselecting the path which has the least cost value to the existing multicast tree; if thepath fails to meet the delay upper bound, the shortest path tree (SPT) based on delaywill be merged into the existing multicast to meet the delay upper bound. Correctnessand performance of DCMPH were analyzed in theory. At the same time, Experimentswere simulated in different aspects. DCMPH algorithm had a high performance inconstructing a DCLC multicast tree and had a lower time complexity than manyDCLC multicast algorithms without breaking the delay upper bound.4) In chapter 5, a delay-constrained dynamic greedy algorithm (DCDG) wasproposed to construct a serial of dynamic multicast trees based on the greedy strategy.By DCDG a computing destination node can join the multicast tree by selecting thepath which meets the delay requirement and has the least cost value to the existingmulticast tree; if the path delay destroys the delay upper bound, the path based onLCSPT will be merged into the existing tree to construct a multicast tree. Correctnessand performance of DCDG were analyzed in theory. The simulation results showedthat DCDG had a high performance in constructing low-cost dynamic multicastrouting trees with a low computing complexity of O(n). And more it achieved a highsuccess ratio under strict delay constrain.5) High-performance multicast routing algorithms for mobile IP were addressedin chapter 6. The operation of RS and BT for mobile multicast was analyzed in detailbased on MIPv6, and simulation experiments were done to compare theirperformance. An idea of "bone node set" was introduced and a multicast routingalgorithm called Bone Node Set-Based Multicast Routing Algorithm (BNSBMR) wasproposed, which can construct multicast tree in mobile IP network. And a distributedversion was developed for BNSBMR. Correctness and performance of BNSBMRwere analyzed. Experiments were simulated according to the simulation model formobile IP. The algorithm had a good performance in cost, short handover latency andlow transfer delay.