Design of optical burst switches based on dual shuffle-exchange network and deflection routing.

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

Scalable design of optical burst switch based on deflection routing.

Deng Yun.Thesis submitted in: July 2003.Thesis (M.Phil.)--Chinese University of Hong Kong, 2004.Includes bibliographical references (leaves 54-56).Abstracts in English and Chinese.Acknowledgments --- p.ii摘要 --- p.iiiAbstract --- p.vChapter Chapter 1 --- Introduction --- p.1Chapter 1.1 --- Optical Switching --- p.1Chapter 1.1.1 --- Optical Circuit Switching --- p.2Chapter 1.1.2 --- Optical Packet Switching --- p.3Chapter 1.1.3 --- Optical Burst Switching --- p.4Chapter 1.2 --- Design of Optical Burst Switching Node --- p.8Chapter 1.2.1 --- Burst Switched Network Architecture --- p.8Chapter 1.2.2 --- Design of Optical Burst Switching Node --- p.10Chapter 1.2.3 --- Scalable Architecture With Multi-plane Fabric --- p.12Chapter 1.3 --- Organization --- p.13Chapter Chapter 2 --- Proposed OBS Node and Blocking probability due to Output Contention --- p.14Chapter 2.1 --- OBS Node Architecture --- p.14Chapter 2.2 --- Burst Traffic Model --- p.16Chapter 2.3 --- Blocking Probability due to Output Contention --- p.17Chapter 2.4 --- Poisson Approximation of Burst Traffic --- p.19Chapter 2.5 --- Simulation Results --- p.21Chapter Chapter 3 --- Deflection Routed Switch Based on Shuffle-exchange network and Burst Loss Rate due to Insufficient Number of Stages --- p.22Chapter 3.1 --- Architecture of Shuffle-exchange Network --- p.22Chapter 3.2 --- The traffic loading entering into the second stage --- p.23Chapter 3.3 --- The Deflection Probability in a 2x2 Switching Module of SN --- p.26Chapter 3.4 --- Analysis of Burst Loss Rate due to Insufficient Number of Stages in SN --- p.27Chapter 3.5 --- Total Burst Loss Probability --- p.30Chapter 3.6 --- Multi-plane Architecture --- p.32Chapter 3.6.1 --- Relationship between k and loading of SN --- p.33Chapter 3.6.2 --- Relationship between k and n: Log2(Number of input-output ports) --- p.36Chapter 3.6.3 --- The result of appropriate number of planes k --- p.38Chapter Chapter 4 --- Switch Based on Dual Shuffle-exchange network and Comparison with Shuffle-exchange network --- p.40Chapter 4.1 --- Architecture of Dual Shuffle-exchange Network --- p.40Chapter 4.2 --- The deflection Probability in a 4x4 Switching Module of DSN --- p.41Chapter 4.3 --- Burst Loss Rate due to Insufficient Number of Stages of DSN --- p.43Chapter 4.4 --- Comparison of SN and DSN --- p.45Chapter 4.4.1 --- Comparison with different n --- p.47Chapter 4.4.2 --- Comparison with different loading --- p.48Chapter 4.4.3 --- The result of comparison --- p.49Chapter Chapter 5 --- Conclusions --- p.50Chapter 5.1 --- The Burst Loss Probability of Proposed OBS Based on SN --- p.51Chapter 5.2 --- The multi-plane Fabric with appropriate number of planes k --- p.51Chapter 5.3 --- Performance of OBS Design Based on DSN and Comparison of SN and DSN --- p.52Bibliography --- p.5

Design of Routers for Optical Burst Switched Networks

Optical Burst Switching (OBS) is an experimental network technology that enables the construction of very high capacity routers using optical data paths and electronic control. In this dissertation, we study the design of network components that are needed to build an OBS network. Specifically, we study the design of the switches that form the optical data path through the network. An OBS network that switches data across wavelength channels requires wave-length converting switches to construct an OBS router. We study one particular design of wavelength converting switches that uses tunable lasers and wavelength grating routers. This design is interesting because wavelength grating routers are passive devices and are much less complex and hence less expensive than optical crossbars. We show how the routing problem for these switches can be formulated as a combinatorial puzzle or game, in which the design of the game board determines key performance characteristics of the switch. In this disertation, we use this formu-lation to facilitate the design of switches and associated routing strategies with good performance. We then introduce time sliced optical burst switching (TSOBS), a variant of OBS that switches data in the time domain rather that the wavelength domain. This eliminates the need for wavelength converters, the largest single cost component of systems that switch in the wavelength domain. We study the performance of TSOBS networks and discuss various design issues. One of the main components that is needed to build a TSOBS router is an optical time slot interchanger (OTSI). We explore various design options for OTSIs. Finally, we discuss the issues involved in the design of network interfaces that transmit the data from hosts that use legacy protocols into a TSOBS network. Ag-gregation and load balancing are the main issues that determine the performance of a TSOBS network and we develop and evaluate methods for both

Novel techniques in large scaleable ATM switches

Bibliography: p. 172-178.This dissertation explores the research area of large scale ATM switches. The requirements for an ATM switch are determined by overviewing the ATM network architecture. These requirements lead to the discussion of an abstract ATM switch which illustrates the components of an ATM switch that automatically scale with increasing switch size (the Input Modules and Output Modules) and those that do not (the Connection Admission Control and Switch Management systems as well as the Cell Switch Fabric). An architecture is suggested which may result in a scalable Switch Management and Connection Admission Control function. However, the main thrust of the dissertation is confined to the cell switch fabric. The fundamental mathematical limits of ATM switches and buffer placement is presented next emphasising the desirability of output buffering. This is followed by an overview of the possible routing strategies in a multi-stage interconnection network. A variety of space division switches are then considered which leads to a discussion of the hypercube fabric, (a novel switching technique). The hypercube fabric achieves good performance with an O(N.log₂N)²) scaling. The output module, resequencing, cell scheduling and output buffering technique is presented leading to a complete description of the proposed ATM switch. Various traffic models are used to quantify the switch's performance. These include a simple exponential inter-arrival time model, a locality of reference model and a self-similar, bursty, multiplexed Variable Bit Rate (VBR) model. FIFO queueing is simple to implement in an ATNI switch, however, more responsive queueing strategies can result in an improved performance. An associative memory is presented which allows the separate queues in the ATM switch to be effectively logically combined into a single FIFO queue. The associative memory is described in detail and its feasibility is shown by laying out the Integrated Circuit masks and performing an analogue simulation of the IC's performance is SPICE3. Although optimisations were required to the original design, the feasibility of the approach is shown with a 15Ƞs write time and a 160Ƞs read time for a 32 row, 8 priority bit, 10 routing bit version of the memory. This is achieved with 2µm technology, more advanced technologies may result in even better performance. The various traffic models and switch models are simulated in a number of runs. This shows the performance of the hypercube which outperforms a Clos network of equivalent technology and approaches the performance of an ideal reference fabric. The associative memory leverages a significant performance advantage in the hypercube network and a modest advantage in the Clos network. The performance of the switches is shown to degrade with increasing traffic density, increasing locality of reference, increasing variance in the cell rate and increasing burst length. Interestingly, the fabrics show no real degradation in response to increasing self similarity in the fabric. Lastly, the appendices present suggestions on how redundancy, reliability and multicasting can be achieved in the hypercube fabric. An overview of integrated circuits is provided. A brief description of commercial ATM switching products is given. Lastly, a road map to the simulation code is provided in the form of descriptions of the functionality found in all of the files within the source tree. This is intended to provide the starting ground for anyone wishing to modify or extend the simulation system developed for this thesis

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