Open Shortest Path First (OSPF) had been recognized as a de facto standard for inter-domain Internet Protocol (IP) routing. Its hierarchical architecture and the introducing of Area Border Router (ABR) had been proved to be an effective solution to the scalability problem. However, manual selection of ABR may fail to accommodate the dynamic change in the network load and therefore lead to sub-optimal solution. There are two new schemes proposed in this thesis. One scheme is Dynamic Appointment ABR for OSPF (DAA-OSPF). Other one scheme is P-median OSPF Partition Algorithm.
DAA-OSPF scheme is proposed for the dynamic appointment of ABR for OSPF. Based on observed traffic demands and knowledge on link capacities, the proposed scheme will dynamically switch to a new ABR from an old one to avoid incipient link congestion and accompanying performance degradation. In response to traffic change,the proposed approach will locate an adequate ABR for the new traffic pattern and then direct traffics to the new ABR. System performance, in terms of link utilization, throughput, and delay, is expected to benefit from the proposed scheme, as demonstrated in the simulation results.
This study also contributes to the issue of stub area partitioning. According to our study, we recognize that the stub area partitioning problem can be well modeled by the P-median problem in logistics [WR99]. In this study, we extend and refine existing approaches to the P-median problem and apply them to the stub area partitioning problem. The refined P-median algorithm is capable of finding out the optical locations of P ABRs in a network such that the total cost is minimized. With the refined P-median algorithm, the proposed OSPF partitioning scheme is expected to minimize the cost of OSPF hierarchical routing, as well as the cost in subsequent packet transmission.
Identifer | oai:union.ndltd.org:NSYSU/oai:NSYSU:etd-0730108-110054 |
Date | 30 July 2008 |
Creators | Tsai, Chen-Da |
Contributors | Hsiao-kuang Wu, Chu-Sing Yang, Rung-Hung Gau, Ren-Hung Hwang, Wei Kuang Lai, Wen Shon Shieh, Hsu-Yang Kung, Sheau-Ru Tong |
Publisher | NSYSU |
Source Sets | NSYSU Electronic Thesis and Dissertation Archive |
Language | English |
Detected Language | English |
Type | text |
Format | application/pdf |
Source | http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0730108-110054 |
Rights | not_available, Copyright information available at source archive |
Page generated in 0.0022 seconds