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)


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


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.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    Moy, J.: OSPF version 2, Internet Draft, RFC 2178 (1997)Google Scholar
  2. 2.
    Dijkstra, E.: A note two problems in connection with graphs. Numerical Math 1 (1959)Google Scholar
  3. 3.
    Paige, R., Kruskal, C.: Parallel algorithms for shortest paths problems. In: Proc. 1989 Intl. Conf. on Parallel Processing, pp. 14–19 (1989)Google Scholar
  4. 4.
    Brodal, G.S., Traff, J.L., Zaroliagis, C.D.: A parallel priority queue with constant time operations. Journal of Parallel and Distributed Computing 49(1), 4–21 (1998)zbMATHCrossRefGoogle Scholar
  5. 5.
    Cohen, E.: Efficient parallel shortest-paths in digraphs with a separator decomposition. J. Algorithms 21, 331–357 (1996)zbMATHCrossRefMathSciNetGoogle Scholar
  6. 6.
    Klein, P., Rao, S., Rauch, M., Subramanian, S.: Faster Shortest-path algorithms for planar graphs. In: Proceedings of the 26th Symposium on Theory of Computation (STOC), pp. 27–37 (1994)Google Scholar
  7. 7.
    Traff, J.L., Zaroliagis, C.D.: A simple parallel algorithm for the single-source shortest pathproblem on planar digraphs. Journal of Parallel and Distributed Computing 60(9), 1103–1124 (2000)CrossRefGoogle Scholar
  8. 8.
    Subramanian, S.: Parallel and Dynamic Shortest-Path Algorithms for Sparse Graphs, PhD Thesis, Brown University (1995)Google Scholar
  9. 9.
    Basu, A., Riecke, J.G.: Stability issues in OSPF. In: Proceedings of ACM SIGCOMM (2001)Google Scholar
  10. 10.
    Francois, P., Filsfils, C., Bonaventure, O., Evans, J.: Achieving Sub-Second IGP Convergence in Large IP Networks. ACM SIGCOMM Computer Communication Review (2005)Google Scholar
  11. 11.
    Shaikh, A., Greenberg, A.: Experience in Black-box OSPF Measurement. In: Proc. ACM SIGCOMM Internet Measurement Workshop (IMW) (2001)Google Scholar
  12. 12.
    Alattinoglu, C., Jacobson, V., Yu, H.: Towards Milli-Second IGP Convergence, draft-alaettinoglu-ISISconvergence-00.txt (2000)Google Scholar
  13. 13.
    OSPF Incremental SPF, Cisco IOS Software Release 12.0 s, [Online]. available:
  14. 14.
    Ramalingam, G., Reps, T.W.: An Incremental Algorithm for a Generalization of the Shortest-Path Problem. Journal of Algorithms 21(2), 267–305 (1996)zbMATHCrossRefMathSciNetGoogle Scholar
  15. 15.
    Narvaez, P., Siu, K.-Y., Tzeng, H.-Y.: New Dynamic Algorithms for Shortest Path Tree Computation. IEEE Transactions on Networking 8(6) (December 2000)Google Scholar
  16. 16.
    Narvaez, P., Siu, K.-Y., Tzeng, H.-Y.: New dynamic SPT algorithm based on a ball-andstring model. IEEE/ACM Transactions on Networking 9, 706–718 (2001)CrossRefGoogle Scholar
  17. 17.
    Xiao, B., Cao, J., Zhuqe, Q., Shao, Z., Sha, E.: Dynamic Update of Shortest Path Tree in OSPF. In: Interna-tional Symposium on Parallel Architectures, Algorithms and Networks (ISPAN 2004) (2004)Google Scholar
  18. 18.
    Wei, L.: Random topology generator (RTG). Univ. of Southern California, Los Angeles, CA. [Online] available:

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

Personalised recommendations