Research On Bandwidth Autonomous And Its Algorithm Based On Bandwidth Constrained Model

With the rapid development of Internet, the main activities of the network transfer from a simple file transfer, e-mail and remote login to multimedia applications and cloud services, etc. they require the network can not only provide the basic communication, but also need the network to provide different services to business with different QoS level. Thus, Research on DiffServ-aware MPLS Traffic Engineering has great significance. DS-TE combines the good scalability of DiffServ and the effective routing strategy of MPLS traffic engineering and allows the regional network resources to be divided in accordance with the class of service. Thus the networks will be subdivided into virtual networks with different QoS capabilities.Firstly, this thesis proposes a new bandwidth constraint model, that is BASM, whose main idea is allows high priority traffics can use the non-allocated resources that reserved for low priority at any time, but low priority traffic classes just use it temporary. Secondly, bandwidth management in DS-TE network architecture is another key research, but most previous studies using offline mode to configure the router, it is not able to react quickly to changes of the network, and to achieve the real response to user demand. To overcome this limitation, the thesis references the idea of Bandwidth Autonomous, whose principle is that the behavior implementate in each node in the network, by monitoring the neighboring nodes unreserved bandwidth and adjusting the local bandwidth, so as to reduce the difference of bandwidth reservation between adjacent nodes, thereby increasing the success rate of business routing and reduce the blocking rate of the algorithm. Thirdly, based on analysis of various previous complete preemption algorithm, we propose a new preemption algorithm, that is Preemption Algorithm with Bandwidth Autonomous based on BASM, whose basic idea is to enhance the node the ability to control the LSP resource, to make the nodes have the ability to manage the LSP bandwidth resources, it implementate Bandwidth Autonomous at the same time when the preemption is going.In order to validate the effectiveness of the designed thought, this article finally has carried on the simulation experiment on the Preemption Algorithm with Bandwidth Autonomous based on BASM, the simulation results show that, compared with no Bandwidth Autonomous and bandwidth allocation under the traditional model, the algorithm proposed in this thesis have the lower cost, the lower blocking rate, the higher link utilization and seize the results more accurate, what is more, it makes the network can adapt to changes of the network environment by optimizing the bandwidth allocation in the network.