Dissertations / Theses on the topic 'Wavelength division multiplexing. Multicasting (Computer networks) Computer networks'

Thesis (Ph. D.)--School of Computing and Engineering. University of Missouri--Kansas City, 2004.
"A dissertation in engineering and computer networking." Advisor: Ghulam Chaudhry. Typescript. Vita. Title from "catalog record" of the print edition Description based on contents viewed Feb. 22, 2006. Includes bibliographical references (leaves 135-157). Online version of the print edition.

Thesis (Ph. D.)--School of Computing and Engineering. University of Missouri--Kansas City, 2007.
"A dissertation in computer networking and telecommunication networking." Advisor: Deep Medhi. Typescript. Vita. Title from "catalog record" of the print edition Description based on contents viewed Jan. 24, 2008. Includes bibliographical references (leaves 130-138). Online version of the print edition.

Thesis (Ph. D.)--Ohio State University, 2003.
Title from first page of PDF file. Document formatted into pages; contains xxvii, 229 p. : ill. Advisor: Ming-Tsan Mike Liu, Department of Computer and Information Science. Includes bibliographical references (p. 219-229).

Les réseaux optiques dynamiques et flexibles font partie des scénarios d'évolution des réseaux de transport optique. Ceux-ci formeront la base de la nouvelle génération des réseaux optiques de demain et permettront le déploiement efficace des services tel que le Cloud Computing. Cette évolution est destinée à apporter flexibilité et automatisation à la couche optique, mais s'accompagne d'une complexité supplémentaire, notamment au niveau de la gestion et de la commande de cette toute nouvelle génération de réseau. Jusqu'à récemment, les protocoles de routage et de signalisation normalisés ont pris en compte plusieurs paramètres physiques tels que l'information spectrale de la bande passante, le format de modulation, et la régénération optique. Cependant, d'autres paramètres sont encore nécessaires (par exemple, les puissances optiques des liens, le gain des amplificateurs) afin de faire fonctionner efficacement de grands réseaux. Dans ce contexte, il y a un besoin d'étudier les réseaux optiques existants ainsi que les différentes méthodes de prise en compte de la couche photonique dans le plan de contrôle. Le but est d'avoir un réseau optique automatique, flexible et programmable, mais surtout efficace de point de vue économique et opérationnel. L'utilisation de la technologie à grille flexible a un impact sur les réseaux optiques existants, où presque tous les équipements devront être remplacés, ce qui entraînera un coût additionnel pour les opérateurs. Dans ce travail, nous étudions les réseaux optiques actuels et évaluons l'impact de la flexibilité sur les infrastructures existantes. Ensuite, nous identifions plusieurs paramètres optiques à contrôler et proposons des extensions protocolaires afin d'intégrer ces paramètres dans un plan de contrôle GMPLS. De plus, nous développons les algorithmes de routage et de signalisation qui permettent la mise en œuvre d'un plan de contrôle efficace qui répond au besoin de la flexibilité. Enfin, l'ensemble de nos propositions et de nos solutions sont évaluées sur plusieurs topologies réseaux avec des modèles de trafic différents dans le but de valider leur pertinence
Dynamic and flexible optical networks are among the evolution scenarios of the optical transport networks. These form the basis of the new generation of optical networks of tomorrow and enable the effective deployment of services such as cloud computing. This evolution is intended to provide flexibility and automation to the optical layer. However, it results in additional complexity, particularly in terms of the management and control of this new network generation. Until recently, the standardized routing and signaling protocols have been taking into account several optical parameters like the spectral bandwidth information, modulation format, and optical regeneration. However, other parameters (e.g., link optical powers, gain of optical amplifiers) are still required in order to efficiently operate large optical networks. In this context, there is a need to study the existing optical networks and the different integration methods of the photonic layer in a control plane. The goal is to get an automatic optical network that is flexible, programmable, and at the same time efficient from an economical and operational perspective. The use of flexible grid technology has an impact on existing optical networks, where almost all the equipment must be replaced, resulting in an additional cost to network operators. In this work, we study the current optical networks and evaluate the impact of flexibility on the existing infrastructures. Then, we identify several physical parameters to be controlled and propose protocol extensions in order to integrate these parameters in the GMPLS control plane. In addition, we develop the routing and signaling algorithms that allow the implementation of an efficient control plane that addresses the need for flexibility. Finally, the set of our proposals and solutions are evaluated on multiple network topologies with different traffic patterns in order to validate their relevance

Technology innovations and capacity upgrades in optical networks have influenced the optical transmission. As a result, network operators are considering separating hardware and software components in order to achieve efficiency and promising savings during network operation and network lifecycle. This leads to resolving the vendor lock-in and opening up the optical networks architectures such that different kinds of disaggregation models can be supported in the DWDM transport layer.In this master thesis, a techno-economic analysis which compares the economical differences between an integrated and disaggregated optical network has been conducted. For the analysis, an actual test case scenario of a European interregional network has been utilized. The line system and transponders components, price lists and features are based on actual vendor components in today’s optical transport networks.According to the results, it has been concluded that all total cost investments required for an integrated or disaggregated approach of DWDM system are traffic dependent. Moreover, capital expenses of open architecture are influenced by business model policy in price reduction due to multiple vendors’ competition on transponders. Calculations demonstrated that a disaggregated approach can introduce considerable total cost savings about 21% less total investments that include 25% less costs for capital expenses and 3% higher cost for operational expenses on an average traffic volume of European network. Finally, by increasing 5-10 times the traffic volume of European network it has been noticed that disaggregated system reduced total cost by 39% and 43% respectively.
Tekniska innovationer och trafiktillväxt påverkar utvecklingen av optisk transmission. En konsekvens av detta är att nätoperatörer undersöker möjligheten att separera hårdvara och mjukvarukomponenter för öka effektiviteten och sänka kostnader för drift. Detta minskar inlåsning till enskilda leverantörer och öppnar upp dom optiska näten för att byggas med olika typer av disaggregering i DWDM transporten.I den här masteruppsatsen har en tekno-ekonomisk analys utförts avseende den ekonomiska skillnaden mellan integrerade och disaggregerade optiska nät. Ett verkligt nät scenario användes för analysen. Komponenter och kostnader för linjesystem och transpondrar är baserade på existerande system och prislistor i dagens nät. Enligt det erhållna resultatet har slutsatsen dragits att totala kostnaden för integrerade och öppna system är trafikberoende. Vidare så är investeringen för öppna system påverkad av pris reduktionen pga. konkurrens på transpondrar.Beräkningarna visar att disaggregerade system kan sänka kostnaderna med 21%, i dessa siffror ingår 25% lägre kostnad för investeringar och 3% högre driftkostnader.Slutligen, genom att öka trafikvolymen med 5 respektive 10 ggr från den ursprungliga trafik matrisen så kan de totala kostnaderna sänkas med 39% och 43%.

Zhang, Shuqiang.
Thesis (M.Phil.)--Chinese University of Hong Kong, 2010.
Includes bibliographical references (p. 74-80).
Abstracts in English and Chinese.
Abstract --- p.i
摘要 --- p.iv
Acknowledgements --- p.v
Table of Contents --- p.vi
Chapter Chapter 1 --- Background --- p.1
Chapter 1.1 --- Routing and Wavelength Assignment --- p.1
Chapter 1.2 --- Survivability in Optical Networks --- p.3
Chapter 1.3 --- Optical Multicasting --- p.4
Chapter 1.3.1 --- Routing and Wavelength Assignment of Optical Multicast --- p.5
Chapter 1.3.2 --- Current Research Topics about Optical Multicast --- p.8
Chapter 1.4 --- Traffic Grooming --- p.10
Chapter 1.4.1 --- Static Traffic Grooming --- p.11
Chapter 1.4.2 --- Dynamic Traffic Grooming --- p.13
Chapter 1.5 --- Contributions --- p.15
Chapter 1.5.1 --- Multicast Protection with Scheduled Traffic Model --- p.15
Chapter 1.5.2 --- Energy Efficient Time-Aware Traffic Grooming --- p.16
Chapter 1.6 --- Organization of Thesis --- p.18
Chapter Chapter 2 --- Multicast Protection in WDM Optical Network with Scheduled Traffic --- p.19
Chapter 2.1 --- Introduction --- p.19
Chapter 2.2 --- Multicast Protection under FSTM --- p.22
Chapter 2.3 --- Illustrative Examples --- p.28
Chapter 2.4 --- Two-Step Optimization under SSTM --- p.37
Chapter 2.5 --- Summary --- p.40
Chapter Chapter 3 --- Energy Efficient Time-Aware Traffic Grooming in Wavelength Routing Networks --- p.41
Chapter 3.1 --- Introduction --- p.41
Chapter 3.2 --- Energy consumption model --- p.43
Chapter 3.3 --- Static Traffic Grooming with Time awareness --- p.44
Chapter 3.3.1 --- Scheduled Traffic Model for Traffic Grooming --- p.44
Chapter 3.3.2 --- ILP Formulation --- p.44
Chapter 3.3.3 --- Illustrative Numerical Example --- p.48
Chapter 3.4 --- Dynamic Traffic Grooming with Time Awareness --- p.49
Chapter 3.4.1 --- Time-Aware Traffic Grooming (TATG) --- p.51
Chapter 3.5 --- Simulation Results of Dynamic Traffic Grooming --- p.54
Chapter 3.5.1 --- 24-node USNET: --- p.55
Chapter 3.5.2 --- 15-node Pacific Bell Network: --- p.59
Chapter 3.5.3 --- 14-node NSFNET: --- p.63
Chapter 3.5.4 --- Alternative Configuration of Simulation Parameters: --- p.67
Chapter 3.6 --- Summary --- p.71
Chapter Chapter 4 --- Conclusions and Future Work --- p.72
Chapter 4.1 --- Conclusions --- p.72
Chapter 4.2 --- Future Work --- p.73
Bibliography --- p.74
Publications during M.Phil Study --- p.80

Centralized light source (CLS) at the central office is an attractive solution for low-cost implementation of WDM-PON, as it eliminates the need of wavelength-specific transmitters and wavelength management at the optical network units (ONU). CLS can be realized by either a carrier-distributed scheme or a remodulation scheme. In both schemes, however, the upstream signal is susceptible to the interferometric crosstalk induced by the beating between the upstream signal and the back-reflected light due to the intrinsic Rayleigh Backscattering (RB), both of which are of the same wavelength. We propose and demonstrate a simple and novel scheme to suppress the RB noise in the carrier-distributed WDM-PON. Differential phase-shift keying (DPSK) is used as the upstream modulation format and the destructive port of the delay-interferometer (DI) is employed to demodulate the upstream DPSK signal. As the spectrum of RB towards the OLT is narrow due to the very narrow spectrum of the distributed carrier, the RB noise can be considerably rejected by the notch filter-like destructive port of the DI at the OLT, which is used simultaneously to demodulate the upstream DPSK signal. The scheme can also be extended to the application in the remodulation-based WDM-PON, as long as the downstream signal has a narrow spectrum (i.e. via reducing downstream modulation depth). A unique feature of the DPSK signal with reduced modulation depth (RMD-DPSK) is that it can be demodulated by DI's destructive port without extinction ratio (ER) degradation, whereas the demodulated signal from DI's destructive port has a very low ER and can be used as the source for upstream remodulation. We also proposed a novel offset-Manchester coding to suppress Rayleigh noise in electrical domain via a postdetection high-pass filter.
Foreseeing the rapidly growing demand for multimedia services and the trend of service convergence, the penetration of optical fiber in access network is an ultimate solution to break the last-mile bottleneck imposed by the 100-year-old copper network. One of the most promising solutions to realize optical access is the passive optical network (PON), in which the network infrastructure is shared by many subscribers and has no active elements between the central office and the customer. Thus a PON requires neither electrical power nor active management, leading to effective reduction in operational expenses. Time-division-multiplexed passive optical networks (TDM-PONs) such as Ethernet PON (EPON) and Gigabit PON (GPON) are being widely deployed in current fiber-based access networks for providing broadband access, offering triple-play services including video, data and voice. In the near future, wavelength-division-multiplexed passive optical network (WDM-PON) can be the enabler of the next-generation optical broadband access that requires large dedicated and symmetric bandwidth, data privacy, and upgrade flexibility. TDM-PONs also can benefit from WDM technologies for capacity upgrade.
With more diverse multimedia and data services available for broadband access, the access network has to be flexible enough to cope with various data or video delivery such as broadcast/multicast services, in addition to the point-to-point traffic. Multicast is more attractive, compared to broadcast, as it allows selective control of the connection for each subscriber individually. Multicast can be easily realized in TDM-PONs as it employs power-splitting at the remote node (RN). However, it is more challenging in WDM-PONs, due to the dedicated connection between the optical line terminal (OLT) and each ONU. Many studies have been carried out to solve this problem. The prior schemes either need relatively complicated multicast control and/or cannot support future proof 10-Gb/s symmetric point-to-point (PtP) transmission. We proposed a novel multicast control scheme for a WDM-PON with 10-Gb/s symmetric bit rate. The multicast data encoded in DPSK format is superimposed onto all PtP channels modulated in inverse return-to-zero format. With an athermal Dr being used at the ONU to demodulate the DPSK signal, the multicast data can be effectively disabled by slight detuning the laser wavelength at OLT, which has negligible effect on the PtP data. The proposed scheme differs from all the previous schemes in that, the multicast control is realized via the inherent wavelength management of WDM systems, rather than via any other additional adjustment such as ER, synchronization, and polarization. v
Xu, Jing.
Adviser: Lian-Kuan Chen.
Source: Dissertation Abstracts International, Volume: 73-06, Section: B, page: .
Thesis (Ph.D.)--Chinese University of Hong Kong, 2011.
Includes bibliographical references.
Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Abstract also in Chinese.

by Chan Tsan Jim.
Thesis (M.Phil.)--Chinese University of Hong Kong, 2003.
Includes bibliographical references (leaves 68-71).
Abstracts in English and Chinese.
Chapter Chapter 1 --- Introduction --- p.1
Chapter 1.1 --- Introduction --- p.1
Chapter 1.2 --- Background --- p.2
Chapter 1.2.1 --- Introduction --- p.2
Chapter 1.2.2 --- Wavelength Division Multiplexing --- p.3
Chapter 1.2.3 --- Arrayed Waveguide Grating --- p.5
Chapter 1.2.4 --- Passive Optical Networks --- p.7
Chapter 1.3 --- Outline of the thesis --- p.10
Chapter Chapter 2 --- Review of Protection and Restoration Schemes --- p.12
Chapter 2.1 --- Introduction --- p.12
Chapter 2.2 --- Protection Schemes --- p.14
Chapter 2.2.1 --- Path Protection --- p.14
Chapter 2.2.2 --- Link Protection --- p.16
Chapter 2.3 --- Restoration Schemes --- p.17
Chapter 2.3.1 --- Path Restoration --- p.17
Chapter 2.3.2 --- Link Restoration --- p.18
Chapter 2.4 --- Protection and Restoration Schemes in PON --- p.18
Chapter 2.4.1 --- Protection Schemes in G.983.1 --- p.18
Chapter 2.4.2 --- Other Proposed Schemes --- p.21
Chapter Chapter 3 --- Design of WDM PON Network Architecture --- p.26
Chapter 3.1 --- Introduction --- p.26
Chapter 3.2 --- The Group Protection Architecture (GPA) --- p.27
Chapter 3.2.1 --- Network Design --- p.27
Chapter 3.2.2 --- Protection Mechanism --- p.28
Chapter 3.2.3 --- Wavelength Assignments --- p.30
Chapter 3.2.4 --- Power Budget Calculation --- p.32
Chapter 3.2.5 --- Crosstalk Analysis --- p.33
Chapter 3.2.6 --- Discussion --- p.35
Chapter 3.3 --- The Enhanced Group Protection Architecture (EGPA) --- p.36
Chapter 3.3.1 --- Introduction --- p.36
Chapter 3.3.2 --- Network Design --- p.37
Chapter 3.3.3 --- Protection Mechanism --- p.38
Chapter 3.3.4 --- Wavelength Assignments --- p.39
Chapter 3.3.5 --- Power Budget Calculation --- p.40
Chapter 3.3.6 --- Crosstalk Analysis --- p.41
Chapter 3.3.7 --- Discussion --- p.42
Chapter 3.4 --- The Hybrid Ring Architecture (HR) --- p.42
Chapter 3.4.1 --- Introduction --- p.42
Chapter 3.4.2 --- Network Design --- p.43
Chapter 3.4.3 --- Protection Mechanism --- p.44
Chapter 3.4.4 --- Wavelength Assignments --- p.45
Chapter 3.4.5 --- Power Budget Calculation --- p.46
Chapter 3.4.6 --- Crosstalk Analysis --- p.47
Chapter 3.4.7 --- Discussion --- p.47
Chapter 3.5 --- Comparison of the three schemes --- p.48
Chapter 3.6 --- Summary of the three schemes --- p.50
Chapter Chapter 4 --- Experimental Evaluation --- p.51
Chapter 4.1 --- Introduction --- p.51
Chapter 4.2 --- Experimental Setup --- p.51
Chapter 4.2.1 --- The GPA Scheme --- p.51
Chapter 4.2.2 --- The EGPA Scheme --- p.53
Chapter 4.2.3 --- The HR Scheme --- p.54
Chapter 4.3 --- Experimental Result --- p.55
Chapter 4.3.1 --- Optical Spectrum --- p.55
Chapter 4.3.2 --- Transmission Performance --- p.58
Chapter 4.3.3 --- Switching/Restoration Time --- p.61
Chapter 4.3.4 --- Crosstalk Penalty --- p.63
Chapter 4.4 --- Conclusion --- p.64
Chapter Chapter 5 --- Conclusion and Future Works --- p.65
Chapter 5.1 --- Introduction --- p.65
Chapter 5.2 --- Conclusion --- p.65
Chapter 5.3 --- Future Works --- p.66
References --- p.67

This thesis focuses on the survivable routing problem in WDM mesh networks where the objective is to minimize the total number of wavelengths used for establishing working and protection paths in the WDM networks. The past studies for survivable routing suffers from the scalability problem when the number of nodes/links or connection requests grow in the network. In this thesis, a novel path based shared protection framework namely Inter-Group Shared protection (I-GSP) is proposed where the traffic matrix can be divided into multiple protection groups (PGs) based on specific grouping policy. Optimization is performed on these PGs such that sharing of protection wavelengths is considered not only inside a PG, but between the PGs. Simulation results show that I-GSP based integer linear programming model, namely, ILP-II solves the networks in a reasonable amount of time for which a regular integer linear programming formulation, namely, ILP-I becomes computationally intractable. For most of the cases the gap between the optimal solution and the ILP-II ranges between (2-16)%. The proposed ILP-II model yields a scalable solution for the capacity planning in the survivable optical networks based on the proposed I-GSP protection architecture.

by Lee Chi Man.
Thesis (M.Phil.)--Chinese University of Hong Kong, 2004.
Includes bibliographical references (leaves 63-65).
Abstracts in English and Chinese.
Chapter CHAPTER 1 --- INTRODUCTION --- p.5
Chapter 1.1 --- Background --- p.5
Chapter 1.1.1 --- Backbone network - Long haul mesh network problem --- p.5
Chapter 1.1.2 --- Access network ´ؤ Last mile problems --- p.8
Chapter 1.1.3 --- Network integration --- p.9
Chapter 1.2 --- SUMMARY OF INSIGHTS --- p.10
Chapter 1.3 --- Contribution of this thesis --- p.11
Chapter 1.4 --- Structure of the thesis --- p.11
Chapter CHAPTER 2 --- PREVIOUS PROTECTION ARCHITECTURES --- p.12
Chapter 2.1 --- Introduction --- p.12
Chapter 2.2 --- Traditional physical protection architectures in metro area --- p.13
Chapter 2.2.1 --- Self healing ring --- p.17
Chapter 2.2.2 --- Some terminology in ring protection --- p.13
Chapter 2.2.3 --- Unidirectional path-switched rings (UPSR) [17] --- p.13
Chapter 2.2.4 --- Bidirectional line-switched rings (BLSR) [17] --- p.14
Chapter 2.2.5 --- Ring interconnection and dual homing [17] --- p.16
Chapter 2.3 --- Traditional physical protection architectures in access networks --- p.17
Chapter 2.3.1 --- Basic architecture in passive optical networks --- p.17
Chapter 2.3.2 --- Fault management issue in access networks --- p.18
Chapter 2.3.3 --- Some protection architectures --- p.18
Chapter 2.4 --- Recent protection architectures on a ccess networks --- p.21
Chapter 2.4.1 --- Star-Ring-Bus architecture --- p.21
Chapter 2.5 --- Concluding remarks --- p.22
Chapter CHAPTER 3 --- GROUP PROTECTION ARCHITECTURE (GPA) FOR TRAFFIC RESTORATION IN MULTI- WAVELENGTH PASSIVE OPTICAL NETWORKS --- p.23
Chapter 3.1 --- Background --- p.23
Chapter 3.2 --- Organization of Chapter 3 --- p.24
Chapter 3.3 --- Overview of Group Protection Architecture --- p.24
Chapter 3.3.1 --- Network architecture --- p.24
Chapter 3.3.2 --- Wavelength assignment --- p.25
Chapter 3.3.3 --- Normal operation of the scheme --- p.25
Chapter 3.3.4 --- Protection mechanism --- p.26
Chapter 3.4 --- Enhanced GPA architecture --- p.27
Chapter 3.4.1 --- Network architecture --- p.27
Chapter 3.4.2 --- Wavelength assignment --- p.28
Chapter 3.4.3 --- Realization of network elements --- p.28
Chapter 3.4.3.1 --- Optical line terminal (OLT) --- p.28
Chapter 3.4.3.2 --- Remote node (RN) --- p.29
Chapter 3.4.3.3 --- Realization of optical network unit (ONU) --- p.30
Chapter 3.4.4 --- Protection switching and restoration --- p.31
Chapter 3.4.5 --- Experimental demonstration --- p.31
Chapter 3.5 --- Conclusion --- p.33
Chapter CHAPTER 4 --- A NOVEL CONE PROTECTION ARCHITECTURE (CPA) SCHEME FOR WDM PASSIVE OPTICAL ACCESS NETWORKS --- p.35
Chapter 4.1 --- Introduction --- p.35
Chapter 4.2 --- Single-side Cone Protection Architecture (SS-CPA) --- p.36
Chapter 4.2.1 --- Network topology of SS-CPA --- p.36
Chapter 4.2.2 --- Wavelength assignment of SS-CPA --- p.36
Chapter 4.2.3 --- Realization of remote node --- p.37
Chapter 4.2.4 --- Realization of optical network unit --- p.39
Chapter 4.2.5 --- Two types of failures --- p.40
Chapter 4.2.6 --- Protection mechanism against failure --- p.40
Chapter 4.2.6.1 --- Multi-failures of type I failure --- p.40
Chapter 4.2.6.2 --- Type II failure --- p.40
Chapter 4.2.7 --- Experimental demonstration --- p.41
Chapter 4.2.8 --- Power budget --- p.42
Chapter 4.2.9 --- Protection capability analysis --- p.42
Chapter 4.2.10 --- Non-fully-connected case and its extensibility for addition --- p.42
Chapter 4.2.11 --- Scalability --- p.43
Chapter 4.2.12 --- Summary --- p.43
Chapter 4.3 --- Comparison between GPA and SS-CPA scheme --- p.43
Chapter 4.1 --- Resources comparison --- p.43
Chapter 4.2 --- Protection capability comparison --- p.44
Chapter 4.4 --- Concluding remarks --- p.45
Chapter CHAPTER 5 --- MUL 77- WA VELENGTH MUL TICAST NETWORK IN PASSIVE OPTICAL NETWORK --- p.46
Chapter 5.1 --- Introduction --- p.46
Chapter 5.2 --- Organization of this chapter --- p.47
Chapter 5.3 --- Simple Group Multicast Network (SGMN) scheme --- p.47
Chapter 5.3.1 --- Network design principle --- p.47
Chapter 5.3.2 --- Wavelength assignment of SGMN --- p.48
Chapter 5.3.3 --- Realization of remote node --- p.49
Chapter 5.3.3 --- Realization of optical network unit --- p.50
Chapter 5.3.4 --- Power budget --- p.51
Chapter 5.4 --- A mulTI- wa velength a ccess network with reconfigurable multicast …… --- p.51
Chapter 5.4.1 --- Motivation --- p.51
Chapter 5.4.2 --- Background --- p.51
Chapter 5.4.3 --- Network design principle --- p.52
Chapter 5.4.4 --- Wavelength assignment --- p.52
Chapter 5.4.5 --- Remote Node design --- p.53
Chapter 5.4.6 --- Optical network unit design --- p.54
Chapter 5.4.7 --- Multicast connection pattern --- p.55
Chapter 5.4.8 --- Multicast group selection in OLT --- p.57
Chapter 5.4.9 --- Scalability --- p.57
Chapter 5.4.10 --- Experimental configuration --- p.58
Chapter 5.4.11 --- Concluding remarks --- p.59
Chapter CHAPTER 6 --- CONCLUSIONS --- p.60
LIST OF PUBLICATIONS: --- p.62
REFERENCES: --- p.63

Wong Chi Sang.
"August 2002."
Thesis (Ph.D.)--Chinese University of Hong Kong, 2002.
Includes bibliographical references.
Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Mode of access: World Wide Web.
Abstracts in English and Chinese.

by Eddie Ting Pong Kong.
Thesis (M.Phil.)--Chinese University of Hong Kong, 1999.
Includes bibliographical references (leaves 61-68).
Abstracts in English and Chinese.
Chapter 1 --- Introduction --- p.1
Chapter 1.1 --- Optical Network Architecture --- p.1
Chapter 1.2 --- High-Speed All-Optical Tunable-Channel Multi-Access Networks --- p.3
Chapter 1.3 --- Fault Surveillance of Optical Cross-Connects in Wavelength Routing Network --- p.3
Chapter 1.4 --- Outline of the Thesis --- p.5
Chapter 2 --- Optical Multi-Access Networks --- p.6
Chapter 2.1 --- All-Optical Networks --- p.6
Chapter 2.2 --- Optical Multi-Access Schemes --- p.8
Chapter 2.2.1 --- Wavelength-Division Multi-Access (WDMA) --- p.9
Chapter 2.2.2 --- Time-Division Multi-Access (TDMA) --- p.12
Chapter 2.2.3 --- Subcarrier Multi-Access (SCMA) --- p.14
Chapter 2.3 --- Design Considerations --- p.14
Chapter 3 --- All-Optical Tunable-Channel Multi-Access Networks --- p.18
Chapter 3.1 --- Tunable-Channel Multi-Access Networks --- p.19
Chapter 3.2 --- Protocols for TCMA Networks --- p.20
Chapter 3.3 --- Photonic Implementation of a Wavelength Division TCMA Network with Time- Slot Access --- p.23
Chapter 3.3.1 --- Proposed Network Architecture --- p.25
Chapter 3.3.2 --- Experimental Results --- p.30
Chapter 3.3.3 --- Discussion --- p.34
Chapter 3.3.4 --- Summary --- p.35
Chapter 4 --- Fault Surveillance for Optical Cross-Connects in Wavelength Routing Networks --- p.36
Chapter 4.1 --- Wavelength Routing Networks --- p.37
Chapter 4.2 --- Options in Fault Surveillance --- p.39
Chapter 4.3 --- Optical Path Surveillance of Optical Cross-Connects in Wavelength Routing Networks --- p.41
Chapter 4.3.1 --- Scanning Amplified Spontaneous Emission Identification Surveillance Scheme --- p.43
Chapter 4.3.2 --- Pilot-Tone Based Surveillance and Removal Scheme --- p.49
Chapter 4.4 --- Summary --- p.55
Chapter 5 --- Conclusion --- p.57
Chapter 5.1 --- Summary of the Thesis --- p.57
Chapter 5.2 --- Future Work --- p.60
Bibliography --- p.61
Publication List --- p.59

Zhang Yu.
Thesis (M.Phil.)--Chinese University of Hong Kong, 2002.
Includes bibliographical references (leaves 67-72).
Abstracts in English and Chinese.
Chapter 1 --- Introduction --- p.1
Chapter 1.1 --- Overview of Optical Networking --- p.1
Chapter 1.2 --- Mechanism in Optical Routing Networks --- p.3
Chapter 1.3 --- Related Work on Optical Routing Networks --- p.4
Chapter 1.4 --- The Motivation of This Thesis --- p.7
Chapter 1.5 --- Thesis Structure --- p.8
Chapter 2 --- Technologies for Multi-dimensional Optical Routing Networks --- p.10
Chapter 2.1 --- Background --- p.10
Chapter 2.2 --- Multi-fiber WDM Networks --- p.11
Chapter 2.2.1 --- Phased-Array-Based WDM Device --- p.11
Chapter 2.2.2 --- Wavelength-tunable lasers --- p.11
Chapter 2.2.3 --- Tunable optical Filter --- p.12
Chapter 2.2.4 --- Wavelength Converter --- p.13
Chapter 2.3 --- OCDM/WDM --- p.16
Chapter 2.3.1 --- Optical En/Decoder --- p.17
Chapter 2.3.2 --- Optical Switch --- p.18
Chapter 2.3.3 --- Optical Code Conversion --- p.18
Chapter 2.4 --- OTDM/WDM --- p.21
Chapter 2.4.1 --- Fast Optical Switch --- p.22
Chapter 2.4.2 --- Optical Time Slot Interchanger (OTSI) --- p.22
Chapter 2.5 --- Conclusion --- p.23
Chapter 3 --- Performance of Code/Wavelength Routing Networks --- p.24
Chapter 3.1 --- Background --- p.24
Chapter 3.2 --- Reconfiguration Capability --- p.25
Chapter 3.3 --- Analytic Models --- p.27
Chapter 3.3.1 --- Trunk Switched Model --- p.27
Chapter 3.3.2 --- Assumptions --- p.28
Chapter 3.3.3 --- Blocking of the Paths with Various Configurations --- p.29
Chapter 3.4 --- Numerical Results --- p.34
Chapter 3.5 --- Conclusion --- p.35
Chapter 4 --- Decomposition Schemes --- p.40
Chapter 4.1 --- Introduction --- p.40
Chapter 4.2 --- Inclusive Converted Networks --- p.41
Chapter 4.3 --- Decompositions --- p.43
Chapter 4.3.1 --- Spatial Decomposition (S.D.) --- p.43
Chapter 4.3.2 --- Dimensional Decomposition (D.D.) --- p.44
Chapter 4.3.3 --- Iterative Decompositions --- p.45
Chapter 4.4 --- Conclusion --- p.46
Chapter 5 --- Performance of Multi-Dimensional Optical Routing Networks --- p.48
Chapter 5.1 --- Homogeneous Trunk Switched Networks --- p.48
Chapter 5.2 --- Analytical Model --- p.49
Chapter 5.3 --- Utilization Gain --- p.53
Chapter 5.4 --- Conversion Gain --- p.54
Chapter 5.5 --- Comparison on the Utilization Gain by Multiplexing and by Conversion --- p.56
Chapter 5.6 --- Conclusion --- p.57
Chapter 6 --- Conclusion --- p.65
Chapter 6.1 --- Summary of the Thesis --- p.65
Chapter 6.2 --- Future Work --- p.66

Nowadays, broadband applications, such as interactive video and multimedia services, have further increased the demand of bandwidth, and thus make high speed multi-wavelength optical access network highly desirable. Wavelength division multiplexing passive optical network (WDM-PON) is a promising candidate to realize the next generation optical access networks due to its dedicated bandwidth for each subscriber and more flexible bandwidth management. As the network traffic is becoming more data-centric, more networking capabilities are required to provide the data service in a more flexible and reliable way. In this thesis, we have proposed and investigated several interesting optical multicast overlay schemes and network protection architectures for WDM-PONs. Optical multicast overlay technique can support the additional multicast transmission on the existing point-to-point data services, while network protection architectures can assure network availability with short traffic restoration time. We will briefly discuss our work in the following sub-topics.
Optical multicast overlay in WDM-PON: Traditional WDM-PONs support only two-way point-to-point data transmission between the optical line terminal (OLT) and the individual subscribers, via the respective designated set of wavelengths. To enhance the network flexibility, it is more desirable to support various different modes of data or video delivery such as broadcast and multicast, in addition to point-to-point transmissions. In this thesis, we systematically investigate the problems and propose our several feasible schemes to overlay multicast transmission onto the existing point-to-point traffic in a WDM-PON. In the first approach, the control of the multicast transmission is achieved by a simple polarization-assisted scheme at the OLT. By the cross-use of wavelengths, a separate path is provided for the multicast differential phase shift keying (DPSK) data from downstream point-to-point amplitude shift keying (ASK) data without additional light sources, which guarantees the transmission performances in both directions, since the upstream ASK signal is imposed on the multicast DPSK signal. We have also demonstrated its variant, in which an optical switch replaces the polarization-assisted control for multicast transmission. The second approach is based on the optical carrier suppression (OCS) technique at the OLT so as to generate the optical subcarriers or sidebands for multicast ASK data modulation. The downstream unicast data is modulated in DPSK format, which will be re-modulated with the upstream ASK data at the respective optical network unit (ONU). As the downstream unicast signal and the upstream signal are calTied on different fiber feeders, while the upstream signal and the multicast signal are carried on different subcarriers, though on the same fiber feeder, the possible Rayleigh backscattering effect is much alleviated. In the third scheme, by using subcarrier modulation technique, we have first successfully overlaid two independent multicast data streams simultaneously onto a WDM-PON, which is believed to further enhance the network capability for multiple destination traffic and improve the cost effectiveness for the future network. Finally, we will provide a comprehensive comparison on all the proposed schemes in this topic.
Survivable network architectures for WDM-PONs: A survivable WDM-PON architecture which can provide self-protection is attractive to avoid enormous loss in data and business due to fiber cuts. To facilitate the network management, the protection switching is realized at the OLT. In this thesis, a simple centrally controlled survivable WDM-PON architecture employing OCS technique is proposed. Protection switching at the OLT employs electrical switches to control the clock signal for the protection sub-carrier generation, via optical carrier suppression. Both distribution and feeder fibers are protected simultaneously. By employing inverse-RZ (IRZ) format for the downstream transmission and non-retum-to-zero (NRZ) for the upstream re-modulated signal, the optical network units are kept colorless and simple. On the other hand, wavelength division multiplexing/time division multiplexing (WDM/TDM) hybrid network, which combines TDM technology and WDM technology, can further increase the network reach, transmission capacity, and reduces the cost per subscriber. Although the bandwidth per subscriber in a WDM/TDM PON is less than that in a WDM-PON, it is still considered as a smooth migration from TDM-PON to WDM-PON. In this thesis, we have proposed a novel WDM/TDM PON architecture which can provide self-protection using a ring topology to connect the subscribers. Finally, we will provide a comprehensive comparison on all the proposed schemes in this topic.
Qiu, Yang.
Adviser: Chun-Kit Chan.
Source: Dissertation Abstracts International, Volume: 73-06, Section: B, page: .
Thesis (Ph.D.)--Chinese University of Hong Kong, 2011.
Includes bibliographical references (leaves 130-140).
Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Abstract also in Chinese.

如今，隨著信息爆炸，骨幹網絡和城域網絡的容量需求已成倍增加。因此，如何提高網絡容量正成為學術界和工業界的熱門話題。可變帶寬光網絡技術通過為不同速率的數據傳輸分配剛剛足夠的帶寬來提高網絡容量，而物理層網絡編碼技術（PNC）在沒有復雜的硬件要求下可以增加網絡容量。在這篇論文中，我們首先提出將組播應用於可變帶寬光網絡來提高網絡容量。我們進一步提出將物理層網絡編碼技術應用於時分複用光接入網絡（TDM-PON），從而來提高全光虛擬專用通信（VPN）的網絡容量。
可變帶寬光網絡中組播的分析
可變帶寬光網絡相比傳統的波分複用光網絡（WDM）可以提高骨幹網絡的頻譜利用率，因為它可以靈活地分配剛剛足夠的帶寬。另一方面，光網絡層上的組播是一種高效的支持點對多點的通信技術。在未來的許多寬帶服務中，點對多點應用服務是必不可少的，通過光組播技術可以節省頻譜帶寬和接發器的數目。為了進一步提高網絡容量，我們建議在可變帶寬光網絡中進行組播。雖然關於可變帶寬光網絡的研究已經有很多了，但據我們所知，關於可變帶寬光網絡的組播尚未被研究。我們通過兩種有效算法來解決可變帶寬光網絡組播的路由和頻譜分配問題。採用相同的路由和波長/頻譜分配算法，我們研究了有靈活帶寬分配產生的好處，通過比較可變帶寬光網絡和傳統波分複用網絡的組播。我們也探討了由非均勻帶寬分配造成的頻譜間隙對提高網絡容量的影響。
時分複用光接入網中(TDM-PON)的物理層網絡編碼技術（PNC）
網絡編碼是一種很有前途的技術，可以提高網絡的容量和健全性。雖然最近有關於在時分複用光接入網中進行網絡編碼的研究，應用於同一個光接入網絡中的光網絡單元（ONU）之間的通信，但在這些研究中的最大的網絡容量提高只有33。此外，在光網路終端（OLT）和光網絡單元中還需要大量的緩衝來存儲VPN數據。在時分複用光接入網中，全光VPN網絡可以重新將VPN數據傳送到相應的ONU，實現ONU之間的直接通信，不需要在OLT進行光-電-光的轉換。在這裡，據我們所知，我們第一次用實驗驗證了一種新方案，將物理層網絡編碼技術應用於TDM-PON，使得全光VPN通信的網絡容量增加了一倍。我們也提出了在光接入網中的遠程節點處使用光環路器，以此減少VPN通信的插入損耗。當兩個ONU之間需要進行雙向通信，可以通過利用PNC來實現全雙工傳輸，相比傳統半雙工的全光VPN方案，網絡容量可以提高100。實驗結果表明，可以實現無差錯全雙工VPN通信，相比半雙工通信功率補償不超過3分貝，而且這方案中ONU間的同步是不需要的。
Nowadays, with the information explosion, the capacity demand has been exponentially increasing in backbone networks and metro networks. Therefore, it is becoming a hot topic for both academic and industry to improve the network capacity. Elastic technologies are promising to scale up the network capacity due to just-enough bandwidth allocation for different data-rate traffic request, while physical-layer network coding (PNC) can increase the throughput without complex requirement on hardware. In this thesis, we first propose a novel scheme to improve the network capacity by implementing multicast in elastic optical networks. We further present the capacity improvement by integrating PNC in time-division multiplexing passive optical network (TDM-PON) for all-optical virtual private network (VPN) communications.
Analysis of multicast in elastic optical networks
Elastic optical networks can increase the spectrum utilization of backbone networks compared to the traditional wavelength-division multiplexing (WDM) networks due to flexible and just-enough bandwidth allocation. On the other hand, multicast over the optical layer is a bandwidth-efficient communication technique which supports point-to-multipoint applications. As many broadband services in the future can be from one source to several destinations, it is essential to enable optical multicast to save bandwidth as well as transceivers. To further improve the network throughput, we propose to implement multicast in spectrum elastic optical networks. Although many investigations on elastic optical networks have been carried out, to the best of our knowledge, the performance of multicast in elastic optical networks have not yet been studied. We develop two efficient multicast heuristics to solve the multicast routing and spectrum allocation (MC-RSA) problem in elastic optical networks. By adopting the same routing and wavelength/spectrum allocation algorithms, the benefits of elastic optical networks resulting from flexible bandwidth allocation are studied for multicast compared to the traditional WDM networks. We also investigate the impact of spectral gap caused by non-uniform bandwidth allocation on the improvement of network throughput.
Physical-layer network coding (PNC) in TDM-PON
Network coding is a promising technique to improve the network throughput and robustness. Although network coding in TDM-PON has been recently investigated for exchanging information among optical network units (ONUs) in the same PON, the maximum capacity improvement of inter-ONU communications in these schemes is only 33%. In addition, large electrical buffer is required to store the VPN traffic at both optical line terminal (OLT) and ONUs. All-optical VPN in TDM-PON can optically reroute VPN traffic to the destined ONU without optical-electrical-optical conversion at OLT, which enables direct communications among ONUs. Here, to the best of our knowledge, for the first time, we experimentally demonstrate a novel PNC scheme integrated in TDM-PON for all-optical VPN communications to double the network throughput. A unique remote node that uses optical circulators to reduce the insertion loss of VPN communications is also proposed. By transmitting two inter-ONU traffic streams of opposite direction simultaneously using PNC (full-duplex), it can improve the network throughput by 100% compared to the traditional all-optical VPN schemes (half-duplex). Experiments show that error-free full-duplex VPN communications are achieved, and the power penalty is no more than 3 dB. Synchronization of ONUs is not required for the proposed scheme.
Detailed summary in vernacular field only.
Detailed summary in vernacular field only.
Detailed summary in vernacular field only.
Detailed summary in vernacular field only.
Detailed summary in vernacular field only.
Wang, Qike.
Thesis (M.Phil.)--Chinese University of Hong Kong, 2012.
Includes bibliographical references (leaves 43-48).
Abstracts also in Chinese.
Chapter Chapter 1 --- Background --- p.1
Chapter 1.1 --- Elastic optical networks --- p.1
Chapter 1.2 --- Multiscast in WDM networks --- p.5
Chapter 1.3 --- Network coding in passive optical network (PON) --- p.7
Chapter 1.4 --- All-optical virtual private nework (VPN) in PON --- p.11
Chapter 1.5 --- Contribution of this thesis --- p.13
Chapter 1.6 --- Organization of this thesis --- p.15
Chapter Chapter 2 --- Analysis of multicast in elastic optical networks --- p.16
Chapter 2.1 --- Introduction --- p.16
Chapter 2.2 --- Network model and heuristics --- p.18
Chapter 2.2.1 --- Multicast-capable node architecture --- p.18
Chapter 2.2.2 --- Multicast goup size (MGS) factor --- p.19
Chapter 2.2.3 --- Network resource and assumption --- p.19
Chapter 2.2.4 --- Multicast routing and spectrum allocation (MC-RSA) heuristics --- p.20
Chapter 2.3 --- Numerical results --- p.22
Chapter 2.4 --- Summary --- p.27
Chapter Chapter 3 --- Physical-layer network coding (PNC) in TDM-PON --- p.28
Chapter 3.1 --- Introduction --- p.28
Chapter 3.2 --- A novel PNC in TDM-PON scheme for all-optical VPN applications --- p.31
Chapter 3.2.1 --- System architecture --- p.31
Chapter 3.2.2 --- Implementation of PNC --- p.32
Chapter 3.2.3 --- Management of wavelength collision --- p.33
Chapter 3.3 --- Experiemnts and results --- p.35
Chapter 3.4 --- Summary --- p.39
Chapter Chapter 4 --- Conclusion and Future Works --- p.40
Chapter 4.1 --- Conclusion of this thesis --- p.40
Chapter 4.2 --- Future works --- p.41
Bibliography --- p.43
List of Publications --- p.50

Choy Man Ting.
Thesis (M.Phil.)--Chinese University of Hong Kong, 2003.
Includes bibliographical references (leaves 66-69).
Abstracts in English and Chinese.
Acknowledgments --- p.ii
Abstract --- p.v
Table of Contents --- p.vii
List of figures --- p.viii
Chapter Chapter 1 --- p.12
Chapter 1.1 --- OBS Network Architecture --- p.3
Chapter 1.2 --- Offset Time and Reservation Schemes --- p.5
Chapter 1.3 --- Research Objectives --- p.7
Chapter 1.4 --- Overview --- p.8
Chapter Chapter 2 --- p.9
Chapter 2.1 --- WDM crossbar architectures --- p.9
Chapter 2.2 --- Switch Based on Optical Crossbars --- p.10
Chapter 2.3 --- Switch Based on Wavelength Grating Routers --- p.11
Chapter Chapter 3 --- p.14
Chapter 3.1 --- Basics of Dual Shuffle Exchange Network --- p.14
Chapter 3.2 --- Dual Shuffle-exchange Network --- p.16
Chapter 3.3 --- Proposed Architecture based on DSN --- p.19
Chapter 3.4 --- Analysis on blocking due to output contention --- p.20
Chapter 3.5 --- Implementation issues on the 4x4 switching module --- p.23
Chapter 3.6 --- Analysis: Non-blocking versus banyan --- p.25
Chapter Chapter 4 --- p.30
Chapter 4.1 --- First Scheme --- p.30
Chapter 4.2 --- Simulation on the first scheme --- p.33
Chapter 4.3 --- Second Scheme: Tunable wavelength converter --- p.37
Chapter 4.4 --- Third Scheme: Route to specific wavelength port --- p.42
Chapter 4.5 --- Analysis on blocking due to insufficient stages --- p.46
Chapter Chapter 5 --- p.49
Chapter 5.1 --- Delay analysis of DSN --- p.49
Chapter 5.2 --- Vertical Expansion --- p.51
Chapter 5.3 --- Simulation results on vertical expansion --- p.52
Chapter 5.4 --- Building DSN with 8x8 MEMS switches --- p.54
Chapter 5.5 --- Prove of the proposed Quarter shuffle network --- p.56
Chapter 5.6 --- Comparison between Quarter shuffle and doubled links approaches --- p.58
Chapter Chapter 6 --- p.64
Conclusion --- p.64
Bibliography --- p.66

This thesis puts focus on the technological challenges for Wavelength Division Multiplexed Passive Optical Network (WDM-PON) implementation, and presents novel semiconductor optical devices for deployment at the optical network unit (ONU). The first-ever reported L-band Reflective semiconductor optical amplifier (RSOA) is presented based on InP-base material. A theoretical model is developed to estimate the optical gain and the saturation power of this device compared to a conventional SOA. Experiments on this device design show long-range telecom wavelength operation, with polarization-independent gain of greater than 20 dB, and low saturation output power of 0 dBm suitable for PON applications. Next, the effect of the amplified spontaneous emission noise of RSOA devices on WDM-PON system is investigated. It is shown through theoretical modeling and simulations that the RSOA noise combined with receiver noise statistics increase probability of error, and induce considerable power penalties to the WDM-PON system. By improving the coupling efficiencies, and by distributing more current flow to the input of these devices, steps can be taken to improve device noise characteristics. Further, in spectrally-spliced WDM-PONs deploying RSOAs, the effect of AWG filter shape on system performance is investigated. Simulation modeling and experiments show that deployment of Flat-band AWGs is critical for reducing the probability of error caused by AWG spectral shape filtering. Flat-band athermal AWGs in comparison to Gaussin-shape counterparts satisfy the maximum acceptable error probability requirements, and reduce the power penalty associated with filtering effect. In addition, detuning between two AWG center wavelengths impose further power penalties to the WDM-PON system. In the last section of this thesis, motivated by RSOA device system limitations, a novel injection-locked Fabry-Perot (IL-FP) device is presented which consists of a gain section monolithically integrated with a phase section. The gain section provides locking of one FP mode to a seed source wavelength, while the phase modulator allows for adjusting the wavelength of the internal modes by tuning bias current to maintain mode-locking. This device counters any mode drifts caused by temperature variations, and allows for cooler-less operation over a wide range of currents. The devices and the performance metrics subsequently allow for a hybrid integration platform on a silicon substrate and integrate many functionalities like reflective modulator with thin film dielectric filter and receiver on a single chip for deployment at the user-end of future-proof low cost WDM-PONs.