The Research Of Traffic Engineering Over MPLS Networks And IP Networks

Information transmitted on network expands greatly with the rapid development of information technology and the wide use of computer network. The speed of information expansion is far beyond that of upgrading network facilities. As a result, in the course of network transmission block arises. Meanwhile, due to the unreasonable design of network, or rather, due to the given drawbacks of the traditional IP network, many network links and facilities have not been fully utilized. The urgent task in the development of current network, the problem that traffic engineering will solve, is to improve the utilization of network resources and its performance. The paper presents the research we have been doing on how to improve the network capacity.There are two main reasons why we do research on traffic engineering. On one hand, it is possible to obtain evident economic benefits by effectively utilizing network facilities. On the other, the emergence of MPLS makes it possible to provide connection-oriented service in traditional IP network.The most important advantage that MPLS can supply in the research on traffic engineering is that it can route IP packets to an LSP(Label Switched Paths). Several (including one) LSPs may be established between a pair of source-destination nodes. The route of each LSP can be independently assigned. Besides, MPLS can segment the aggregate traffic into routable subsets (FECs), and each FEC may be routed over multiple paths (LSPs) to achieve an optimal purpose.The research objective of the paper is to propose solutions to traffic engineering over MPLS and traditional IP. The aims are to maximize the utilization of network resources, or to reach the objectives of optimal distribution traffic in constraining conditions. The paper is theoretically based on modern network optimization, including Graph Theory, Optimization, Operation Research, Network Management. The main computer technology adopted is MPLS over IP network..The paper first gives a mathematical definition of traffic engineering, abstracting into mathematical problems network topology, traffic, demands, routes, network state. Several major drawbacks of the current IP network architecture are then analyzed from the angle of traffic engineering, followed by the summary of the background knowledge and architecture of MPLS and the key technology in realizing traffic engineering over MPLS.The analysis of the research process of traditional IP routing and QoS routing follows the introduction of the past and present research of traffic engineering. The latest research results of current MPLS traffic engineering are presented. Related theories of network optimization are summarized. Optimal methods used in traffic engineering and constrained-routes are stated. According to the object-function, decision variables and constraining conditions several types of optimal problems and solutions are proposed. Summaries are made concerning the typical network optimization problem.The paper independently puts forward several optimal methods to improve network traffic transmission, such as the maximum-flow problem over MPLS, including the arc-based and path-based solution, which adopt the method of splitting and unsplitting traffic, the solution to the greatest reliability of transmission, the solution to concurrent maximum-flow for load balance via linear programming. On the basis of MPLS path protection several protection methods over MPLS are proposed, including N-to-1, N-to-M protection solution in splitting and unsplitting cases and in DiffServ cases, whose partial simulation results are provided as well. The programming formulas of N-to-M path protection are proposed. In the research project of Shandong Province one scheme, on the basis of network application layer, is put forward and realized, in which load balance method based on web explorer is original. The design thought and development of the project is introduced in detail.