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Parallel Dynamic SPT Update Algorithm in OSPF

  • Yuanbo Zhu
  • Mingwei Xu
  • Qian Wu
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4671)

Abstract

Shortest-Path-Tree (SPT) computation, as the main load in OSPF protocol, contributes to the slow convergence time in intra-domain routing. With the increasing interest for upcoming routers of multi-core based processing board, efficient parallel routing algorithms are required to take this advantage to speedup SPT computation in order to meet the needs for fast failure recovery applications such as VoIP. However, currently available parallel SPT algorithms are all based on static method, which re-computes the entire tree for each link change. In this paper, we explore parallel algorithms for dynamic SPT update, a more efficient method, which only updates the affected nodes by making use of the previous SPT We first analyze characters of dynamic method to show how they affect parallel design; then we give our parallel dynamic SPT algorithm framework, which uses: (1) parallel distance-updating mode, to get a near liner speedup (assuming perfect load balance) and (2) group-removal schema, to reduce communication cost. Further, to provide load balance, we give a task distribution algorithm called RR_DFS, which makes use of the topology information of the previous SPT. Complexity analysis and simulation result are also presented

Keywords

Load Balance Network Size Parallel Algorithm Communication Time Queue Size 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2007

Authors and Affiliations

  • Yuanbo Zhu
    • 1
  • Mingwei Xu
    • 1
  • Qian Wu
    • 1
  1. 1.Computer Science Department, Tsinghua University, Beijing 100084China

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