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Contributions to Network Planning and Operation of Flex-Grid/SDM Optical Core Networks

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Contributions to Network Planning and Operation of Flex-Grid/SDM Optical Core Networks Contributions to Network Planning and Operation of Flex-Grid/SDM Optical Core Networks by Rubén Rumipamba-Zambrano A thesis submitted in fulfillment for the degree of Doctor of Philosophy in the Broadband Communications Research Group (CBA) Computer Architecture Department (DAC) February 2019 Contents List of Figures .............................................................................................................................. 7 List of Tables ............................................................................................................................. 11 Abbreviations and Symbols ...................................................................................................... 13 Summary .................................................................................................................................... 19 Resumen ..................................................................................................................................... 21 Resum ......................................................................................................................................... 23 Acknowledgments ..................................................................................................................... 27 1 Introduction ......................................................................................................................... 1 1.1 Motivation ..................................................................................................................... 1 1.2 Objectives ...................................................................................................................... 2 1.3 Methodology ................................................................................................................. 3 1.4 Thesis Organization....................................................................................................... 4 2 Background and related work ........................................................................................... 7 2.1 Flex-grid technology ..................................................................................................... 7 2.2 Space Division Multiplexing (SDM) technology .......................................................... 8 2.2.1 SDM transmission medium ................................................................................... 9 2.3 Flex-Grid/SDM networks ............................................................................................ 11 2.3.1 SDM-ROADM solutions ..................................................................................... 12 2.3.2 Super-channel allocation required by SDM-ROADMs ...................................... 17 2.4 Resource allocation in Flex-Grid/SDM networks ....................................................... 19 2.4.1 Network planning scenarios ................................................................................ 21 2.4.2 Network operation scenarios ............................................................................... 22 3 Spatially fixed Flex-Grid/SDM optical networks ........................................................... 25 3.1 Network operation scenario ........................................................................................ 26 3.1.1 TR estimations for Flex-Grid/SDM networks ..................................................... 26 3.1.2 Impact of spatial super-channel guard-bands ...................................................... 28 3.1.2.1 Characteristics of spatial super-channels ........................................................ 28 3.1.2.2 Simulation results ............................................................................................ 30 iii iv Contents 3.1.3 Cost-effective spatial super-channel configuration ............................................. 32 3.1.3.1 Full Space Assignment (FSA) strategy ........................................................... 34 3.1.3.2 Partial Space Assignment (PSA) strategy ....................................................... 35 3.1.3.3 Comparison of PSA and FSA strategies .......................................................... 36 3.1.3.4 ICXT Impact Analysis .................................................................................... 40 3.1.4 Network throughput vs. spatial multiplicity analysis .......................................... 42 3.1.4.1 SCh allocation in spatially fixed Flex-Grid/SDM networks ........................... 43 3.1.4.2 Simulation results ............................................................................................ 46 3.1.5 Dynamic end-to-end spatial traffic grooming ..................................................... 49 3.1.5.1 Methodology for dynamic e2e-grooming ........................................................ 49 3.1.5.1.1 RMSSA heuristic ......................................................................................... 51 3.1.5.2 Simulation results ............................................................................................ 51 3.2 Planning of optimal MIMO assignment for MCF-enabled networks ......................... 54 3.2.1 Problem statement ............................................................................................... 56 3.2.2 Optimal problem solution .................................................................................... 57 3.2.2.1 Candidate lightpath pre-computation .............................................................. 58 3.2.2.2 ILP formulations ............................................................................................. 59 3.2.3 Heuristic approaches ........................................................................................... 60 3.2.4 Simulation results ................................................................................................ 64 3.2.4.1 Scenario under study ....................................................................................... 65 3.2.4.2 Metaheuristic Performance Validation ............................................................ 65 3.2.4.3 MIMO equalization and spectral requirements benefits ................................. 69 3.2.4.4 MIMO complexity and crosstalk compensation.............................................. 72 3.3 Conclusions ................................................................................................................. 75 4 Operation of Spectrally and Spatially Flexible Optical Networks (SS-FONs) ............ 77 4.1 SCh allocation in SS-FONs ......................................................................................... 77 4.1.1 Weighted Spectral and Spatial Allocation (WSSA) ............................................ 79 4.1.2 RMSSA greedy heuristic for SS-FONs ............................................................... 81 4.2 Performance of SS-FONs ............................................................................................ 83 Contents v 4.2.1 Impact of SCh configuration on network throughput.......................................... 83 4.2.2 Network throughput vs. spatial multiplicity analysis .......................................... 87 4.2.3 BVT complexity analysis .................................................................................... 91 4.3 Conclusions ................................................................................................................. 93 5 SDM-ROADMs without spatial conversion for SS-FONs ............................................. 95 5.1 SDM-ROADM architectures with/without spatial conversion ................................... 96 5.2 Impact of spatial conversion on the performance and cost of SS-FONs ..................... 99 5.2.1 Network planning scenario ................................................................................ 100 5.2.1.1 Problem statement ......................................................................................... 100 5.2.1.2 Optimal problem solution .............................................................................. 101 5.2.1.3 Heuristic approach ......................................................................................... 103 5.2.1.4 Simulation results .......................................................................................... 104 5.2.2 Network operation scenario............................................................................... 110 5.2.2.1 RMSSA heuristic ........................................................................................... 111 5.2.2.2 Impact of spatial conversion on network performance ................................. 112 5.2.2.3 Impact of spatial conversion on network cost ............................................... 118 5.3 Conclusions ............................................................................................................... 120 6 Final Discussion and Future Work ................................................................................ 123 Appendix A .............................................................................................................................. 127 A Reference transport networks ........................................................................................ 127 Appendix B .............................................................................................................................. 131 B Publication List ...............................................................................................................
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