Traffic grooming in bidirectional WDM ring networks

Authors

  • Jean-Claude Bermond,

    1. Mascotte Joint Project I3S (CNRS/UNS) and INRIA - 2004, route des Lucioles - Sophia Antipolis, France
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  • Xavier Muñoz,

    1. Graph Theory and Combinatorics group at Applied Mathematics IV Department of UPC, Barcelona, Spain
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  • Ignasi Sau

    Corresponding author
    1. Graph Theory and Combinatorics group at Applied Mathematics IV Department of UPC, Barcelona, Spain
    2. Mascotte Joint Project I3S (CNRS/UNS) and INRIA - 2004, route des Lucioles - Sophia Antipolis, France
    • Mascotte Joint Project I3S (CNRS/UNS) and INRIA - 2004, route des Lucioles - Sophia Antipolis, France
    Search for more papers by this author

  • An extended abstract of this article was presented at ICTON'06 [9].

Abstract

We study the minimization of ADMs (Add-Drop Multiplexers) in optical WDM bidirectional rings considering symmetric shortest path routing and all-to-all unitary requests. We precisely formulate the problem in terms of graph decompositions, and state a general lower bound for all the values of the grooming factor C and N, the size of the ring. We first study exhaustively the cases C = 1, C = 2, and C = 3, providing improved lower bounds, optimal constructions for several infinite families, as well as asymptotically optimal constructions and approximations. We then study the case C > 3, focusing specifically on the case C = k(k + 1)/2 for some k ≥ 1. We give optimal decompositions for several congruence classes of N using the existence of some combinatorial designs. We conclude with a comparison of the cost functions in unidirectional and bidirectional WDM rings. © 2010 Wiley Periodicals, Inc. NETWORKS, Vol. 58(1), 20–35 2011

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