IP multicast over WDM networks

Ph.DDOCTOR OF PHILOSOPH

A bandwidth relocatable lightwave backbone network.

Lee Chun Ming.Thesis (M.Phil.)--Chinese University of Hong Kong, 1994.Includes bibliographical references (leave 45).List of Figures --- p.iiiList of Tables --- p.ivAcknowledgement --- p.vAbstract --- p.viChapter I --- Introduction --- p.1Chapter II --- Architecture of The Proposed Lightwave Backbone Network --- p.4Chapter III --- Wavelength Conflicts Problem --- p.8Chapter IV --- Network Dimensioning Problem --- p.10Chapter A. --- Integer Programming Formulation --- p.10Chapter V --- Capacity Apportionment (CA) Problem --- p.17Chapter A. --- Integer Programming Formulation --- p.17Chapter B. --- Heuristic Algorithm --- p.19Chapter C. --- An Illustrative Example For The Hueristic Algorithm --- p.21Chapter VI --- Wavelength Channel Assignment Problem --- p.24Chapter A. --- Wavelength Channel Assignment Strategies --- p.24Chapter B. --- Dynamic Wavelength Channel Assignment Algorithms --- p.25Chapter C. --- Performance Results By simulation --- p.33Chapter D. --- Comparison Of Blocking Performance Between Static And Dynamic Wavelength Channel Assignment Scheme --- p.40Chapter VII --- Conclusion --- p.42References --- p.45Appendix A Wavelength channel assignment plan generated by the heuristic algorithm for the illustrative example in section V --- p.4

Nodal distribution strategies for designing an overlay network for long-term growth

Scope and Method of Study:This research looked at nodal distribution design issues associated with building an overlay network on top of an existing legacy network with overlay network switches and links not necessarily matching the switch and link locations of the underlying network. A mathematical model with two basic components, switch costs and link costs, was developed for defining the total cost of a network overlay. The nature of the underlying legacy topology determines the dominant factor, link or switch costs to the total cost function as well as the unit cost for switches and links.Findings and Conclusions:The three design heuristics presented first, locate overlay switches at nodes in the center of the legacy network as opposed to the periphery; second, locate overlay switches at legacy nodes with high connectivity; and third, locate overlay switches at legacy nodes with high traffic flow demands, can be used to help point to the direction of keeping costs under control when design changes are required. Applying the concept of efficient frontiers to the world of network design and building a suite of best designs gives the network designer greater insight into how to design the best network in the face of changing real-world constraints. For the cost model and the case studies evaluated using the design strategies in this study, distributed approaches generally tend to be a good choice when the link costs dominate the total cost function because total path distances and therefore link costs need to be minimized in preference over switch costs. A distributed overlay tends to have lower link costs because there is usually a greater probability that total path distances can be minimized because of greater connectivity. More connections set up the potential for more traffic flow path choices allowing each traffic flow to be sent along shorter paths. In legacy network topology designs that have many nodes with high connectivity, the overlay link costs can be relatively similar between designs and the switch costs can have a large impact upon total cost

Advances in Optical Amplifiers

Optical amplifiers play a central role in all categories of fibre communications systems and networks. By compensating for the losses exerted by the transmission medium and the components through which the signals pass, they reduce the need for expensive and slow optical-electrical-optical conversion. The photonic gain media, which are normally based on glass- or semiconductor-based waveguides, can amplify many high speed wavelength division multiplexed channels simultaneously. Recent research has also concentrated on wavelength conversion, switching, demultiplexing in the time domain and other enhanced functions. Advances in Optical Amplifiers presents up to date results on amplifier performance, along with explanations of their relevance, from leading researchers in the field. Its chapters cover amplifiers based on rare earth doped fibres and waveguides, stimulated Raman scattering, nonlinear parametric processes and semiconductor media. Wavelength conversion and other enhanced signal processing functions are also considered in depth. This book is targeted at research, development and design engineers from teams in manufacturing industry, academia and telecommunications service operators