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Offset Time-Emulated Architecture for Optical Burst Switching - Modelling and Performance Evaluation Autor De La Tesi: Mirosław Klinkowski

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Offset Time-Emulated Architecture for Optical Burst Switching - Modelling and Performance Evaluation Autor De La Tesi: Mirosław Klinkowski Universitat Politecnica` de Catalunya Departament d'Arquitectura de Computadors O®set Time-Emulated Architecture for Optical Burst Switching - Modelling and Performance Evaluation Ph.D. thesis by MirosÃlaw Klinkowski Advisor: Dr. Davide Careglio Co-advisors: Prof. Josep Sol¶ei Pareta, and Prof. Marian Marciniak PhD Program: Arquitectura i Tecnologia de Computadors November 2007 ACTA DE QUALIFICACIÓ DE LA TESI DOCTORAL Reunit el tribunal integrat pels sota signants per jutjar la tesi doctoral: Títol de la tesi: Offset Time-Emulated Architecture for Optical Burst Switching - Modelling and Performance Evaluation Autor de la tesi: Mirosław Klinkowski Acorda atorgar la qualificació de: No apte Aprovat Notable Excel·lent Excel·lent Cum Laude Barcelona, …………… de/d’….................…………….. de ..........…. El President El Secretari ............................................. ............................................ (nom i cognoms) (nom i cognoms) El vocal El vocal El vocal ............................................. ............................................ ..................................... (nom i cognoms) (nom i cognoms) (nom i cognoms) To Ola and my parents Acknowledgments to Marian, Josep, Davide, and MichaÃl for their measureless support, inspiration and for guiding me through the research of this thesis Wala, Barbara, Andrzej and MichaÃl for encouraging me at the very beginning of this thesis And to my family for their love, support, and for being always with me Contents List of Figures v List of Tables ix Summary xi Resum xv Structure of the thesis xix 1 Introduction 1 1.1 Optical Transport Networks . 2 1.2 Overview of the Thesis . 4 PART I: Background 7 2 Optical switching architectures 9 2.1 Principle of operation . 10 2.1.1 Optical circuit switching (OCS) . 10 2.1.2 Optical packet switching (OPS) . 10 2.1.3 Optical burst switching (OBS) . 11 2.1.4 OPS vs. OBS . 11 2.2 Main characteristics and comparison between OCS, OBS, and OPS . 12 2.3 Summary . 18 3 Optical burst switching 21 3.1 Overview of general OBS concepts . 22 3.1.1 Signalling . 22 3.1.2 Architectures and functions of OBS nodes . 24 3.1.3 O®set time provisioning . 27 3.1.4 Resources reservation . 30 3.1.5 Contention resolution . 31 3.1.6 Burst scheduling . 33 3.1.7 Quality of service provisioning . 34 3.1.8 Network routing . 34 i ii PART II: O®set Time-Emulated OBS Architecture 37 4 E-OBS architecture 39 4.1 Principles of E-OBS . 39 4.1.1 Node architecture . 39 4.1.2 Control operation . 41 4.2 Characteristics of E-OBS and C-OBS . 42 4.3 Summary . 48 5 Modelling of E-OBS control plane 49 5.1 Introduction . 49 5.2 Modelling of control plane . 50 5.2.1 Control plane impacting factors . 50 5.2.2 A queuing model of OBS switch controller . 52 5.3 E-OBS controller with a single processor . 52 5.3.1 Queuing models . 52 5.3.2 Results . 54 5.4 Summary . 57 PART III: Quality of service provisioning 59 6 QoS provisioning in OBS networks 61 6.1 Basic concepts of QoS in OBS networks . 62 6.1.1 QoS metrics . 62 6.1.2 Absolute vs. relative QoS guarantees . 62 6.1.3 QoS in connection-oriented and connection-less OBS . 63 6.2 Categories of QoS mechanisms in OBS networks with one-way signalling 63 6.2.1 Control plane-related mechanisms . 63 6.2.2 Edge-based mechanisms . 64 6.2.3 Core-based mechanisms . 65 7 Performance of QoS mechanisms in E-OBS 69 7.1 Overview . 69 7.1.1 QoS scenario details . 69 7.1.2 Simulation scenario . 71 7.2 Threshold selection in BD-W mechanism . 71 7.3 Performance results . 73 7.3.1 Burst loss probability and throughput . 73 7.3.2 Burst preemption vs. o®set time di®erentiation . 74 7.4 Summary . 76 8 E®ective burst preemption in E-OBS 77 8.1 Preemption rate in a bu®er-less OBS node . 77 8.2 Preemption Window (PW) mechanism . 79 8.2.1 Principles . 80 iii 8.2.2 The length of preemptive window . 81 8.3 A single-wavelength model of PW mechanism . 82 8.3.1 Some remarks . 85 8.4 Computer simulation of PW mechanism . 86 8.4.1 Simulation scenario . 86 8.4.2 Numerical results . 87 8.4.3 PW and FDL bu®ering . 89 8.5 Summary . 90 PART IV: Routing 91 9 Routing in OBS networks 93 9.1 Introduction . 93 9.1.1 Routing terminology . 93 9.1.2 Reactive and proactive burst loss reduction techniques . 95 9.1.3 Hop-by-hop vs. explicit routing . 96 9.2 State of the art . 97 9.2.1 Alternative routing . 97 9.2.2 Multi-path routing . 98 9.2.3 Single-path routing . 99 9.3 Summary . 100 10 Isolated alternative routing strategies for labelled E-OBS networks101 10.1 Scenario under study . 101 10.2 Algorithms . 104 10.3 Results . 106 10.4 Summary . 106 11 Optimization of multi-path routing 111 11.1 Routing scenario . 111 11.2 Formulation . 112 11.2.1 Loss models of OBS network . 112 11.2.2 Optimization problem . 115 11.3 Partial derivatives . 116 11.3.1 NR-LL model . 116 11.3.2 R-LL model . 118 11.3.3 Remarks . 118 11.4 Implementation issues . 119 11.5 Performance . 120 11.5.1 Comparison of routing schemes . 120 11.6 Summary . 123 iv PART V: Conclusions and future works 125 12 Conclusions and future works 127 Acronyms 131 Bibliography 133 A Related publications 149 A.1 Papers . 149 A.2 Papers under submission . 152 A.3 Contribution to European projects . 152 A.4 Other publications . 152 List of Figures 1.1 Generic architecture of optical DWDM network. 2 1.2 The trend of migration in optical networking. (courtesy of [Pro05]) . 3 2.1 Optical circuit switching network. 10 2.2 Optical packet switching network. 11 2.3 Optical burst switching network. 12 2.4 Overview over key parameters determining circuit/burst/packet gran- ularity and required switching technology. 13 3.1 Signalling protocols in OBS networks. 23 3.2 OBS ingress edge node. 25 3.3 Burst control packet format. 26 3.4 OBS core switching node. 27 3.5 O®set time provisioning architectures. 29 3.6 Resources reservation schemes. 31 3.7 Contention resolution mechanisms. 32 3.8 Burst scheduling algorithms. 34 4.1 General E-OBS core node architecture. 40 4.2 Fiber delay coils; a) a single component, b) a part of an OBS test-bed. (courtesy of Newport Corp., and OITDA) . 40 4.3 Time dependencies in E-OBS. 41 4.4 Unfairness in conventional OBS. 42 4.5 Burst loss probability vs. remaining hops number. 43 4.6 Burst loss probability vs. o®ered tra±c load. 44 4.7 JIT resources reservation in a) C-OBS, and b) E-OBS. 45 5.1 Data and control networks of OBS. 50 5.2 Exemplary controller architectures. 51 5.3 General OBS control-plane queuing model. 52 5.4 Queuing models: a) M/M/1 with reneging, b) M/D/1/K. 53 5.5 Intensity of control packet arrival. 54 5.6 Loss probability of control packets. 55 5.7 Delay budget vs. normalized mean burst duration. 56 5.8 Delay budget vs. average burst length. 56 6.1 Categories of QoS mechanisms in OBS networks. 64 v vi 6.2 Selected QoS mechanisms in OBS networks. 65 7.1 Evaluated QoS network scenario. 70 7.2 Performance of BD-W mechanism (c = 8), a) HP class BLP, b) LP class ¡4 BLP, c) throughput, d) threshold value guaranteeing.
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