Two strategies for solving the vertex cover problem on a transputer network

  • R. Lüling
  • B. Monien
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 392)


In this article, we present an implementation of a distributed branch and bound algorithm solving the Vertex Cover problem on a network of up to 63 Transputers.

We implemented two different strategies: The first parallelization of our branch and bound algorithm is fully distributed. Every processor performs the same algorithm but on a different part of the solution tree. In this case it is necessary to distribute subproblems among the processors to achieve a well balanced workload.

Our second strategy is based on a tree structured network, where all subproblems are stored at the root processor and the other processes work as slaves of this master process.

To show the performance of our strategies, we solved the Vertex Cover problem for graphs of up to 150 nodes and an average degree of 30. We were able to achieve a speedup of 57.35 for the first strategy on a 60 processor network and 62.11 for the second strategy on 63 processors, compared to a very efficient sequential algorithm.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1989

Authors and Affiliations

  • R. Lüling
    • 1
  • B. Monien
    • 1
  1. 1.Department of Mathematics and Computer ScienceUniversity of PaderbornWest Germany

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