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

O problema das fraudes virtuais em serviços de Internet Banking e comércio eletrônico vem crescendo a cada dia. Em 2005, as fraudes virtuais representaram, no Brasil, uma perda de 300 milhões de reais. Neste trabalho, apresentamos inicialmente o cenário atual das fraudes, especificando quais ataques elas utilizam, como são hoje executadas e quais vulnerabilidades exploram. Cada ataque é classificado conforme uma nova taxonomia criada. São também apresentadas possíveis defesas contra esses ataques, indicando a efetividade de cada uma. Analisamos também o ponto de vista da privacidade do usuário para cada uma dessas soluções. Como contribuição original, esse trabalho apresenta uma solução de curto prazo, que opera sobre a infra-estrutura já existente, que visa reduzir o problema das fraudes. São feitas também considerações sobre possíveis soluções de longo prazo de maior efetividade e que promovam uma defesa mais estrutural. / The problem of virtual frauds in Internet Banking and electronic commerce services is growing each day. In 2005, the virtual frauds represented a damage of 300 million reais in Brazil. In this work, we present initially the current scenario of virtual frauds, specifying what attacks are used, how they are executed and which vulnerabilities they exploit. Each attack will be classified in accordance to a new methodology. We also present defenses against these attacks, indicating the effectiveness and intrusion of each one of them. In the end, a short term and defensive solution is presented to reduce the problem of virtual frauds. We also consider long term solutions that could be used in the future to accomplish structural defenses.

Devido à importância dos firewalls para proteção de redes de computadores, muito se estuda no sentido do aprimoramento das técnicas de proteção e no desenvolvimento de novas técnicas para serem utilizadas na análise destes. Com enfoque neste tema, esta dissertação trata a respeito da viabilidade da técnica de injeção de pacotes e observação dos resultados para analisar o comportamento de firewalls de rede para a pilha TCP/IP, resultando em uma técnica alternativa para análise de firewalls. Para mostrar a validade da técnica foi proposta uma arquitetura e, como prova de conceito, foi implementado um protótipo do sistema de análise. Foram também efetuados alguns testes. A técnica de injeção de pacotes e observação dos resultados mostrou-se viável para algumas situações. Para outras, são necessárias estudos adicionais para redução da explosão combinatória. / Due to the importance of the firewalls for protection of network computers, a lot of studies has been done in order of the improvement of the protection techniques and in the development of new techniques to be used in the analysis of them. With focus in this theme, this thesis considers the viability of the technique of injection of packages and observation of the results to analyze the behavior of network firewalls for stack TCP/IP, resulting in an alternative technique for analysis of firewalls. To show the validity of the technique an architecture was proposed and, as a concept proof, a prototype of the analysis system was implemented. Also was implemented some tests. The technique of injection of packages and observation of the results reveled viable for some situations. For others, addictionals studies are necessary for reduction of the combinatory explosion.

Zhao, Qiao. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 35-36). / Abstracts also in Chinese. / Abstract --- p.i / Acknowledgement --- p.v / Chapter 1 --- Introduction --- p.1 / Chapter 2 --- Model Description --- p.3 / Chapter 2.1 --- An Incentive Model for P2P Networks --- p.3 / Chapter 2.2 --- Learning Models for P2P Networks --- p.5 / Chapter 2.2.1 --- Current-best Learning Model (CBLM) --- p.5 / Chapter 2.2.2 --- Opportunistic Learning Model (OLM) --- p.6 / Chapter 2.3 --- Incentive Policies for P2P Networks --- p.7 / Chapter 2.3.1 --- Mirror Incentive Policy Vmirror --- p.8 / Chapter 2.3.2 --- Proportional Incentive Policy Vprop --- p.9 / Chapter 2.3.3 --- Linear Incentive Policy Class CLIP --- p.9 / Chapter 2.4 --- Performance and Robustness of Incentive Policies --- p.10 / Chapter 2.4.1 --- Robustness Analysis of Mirror Incentive Policy using the current-best learning method --- p.10 / Chapter 2.4.2 --- Robustness Analysis of Mirror Incentive Policy using the opportunistic learning method --- p.12 / Chapter 2.4.3 --- Robustness Analysis of Proportional Incentive Policy Using the current-best learning method --- p.12 / Chapter 2.4.4 --- Robustness Analysis of Proportional Incentive Policy Using the opportunistic learning method --- p.13 / Chapter 2.4.5 --- Robustness Analysis for Incentive Protocol in the Linear Incentive Class --- p.14 / Chapter 2.5 --- Connection with Evolutionary Game Theory --- p.17 / Chapter 3 --- Performance Evaluation --- p.21 / Chapter 3.1 --- Performance and Robustness of the Mirror Incentive Policy (Pmirror): --- p.21 / Chapter 3.2 --- Performance and Robustness of the Proportional Incentive Policy {Pprop): --- p.23 / Chapter 3.3 --- Performance and Robustness of incentive policy in the Linear Incentive Class (CLIP)： --- p.24 / Chapter 3.4 --- The Effect of Non-adaptive Peers: --- p.25 / Chapter 4 --- Adversary Effect of Altruism --- p.29 / Chapter 4.1 --- The Effect of Protocol Cost --- p.29 / Chapter 4.2 --- The Tradeoff between Altruism and System Robustness --- p.30 / Chapter 5 --- Related Work --- p.33 / Chapter 6 --- Conclusion --- p.34 / Bibliography --- p.35

Lam, Kim Yung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 87-92). / Abstract also in Chinese. / Abstract --- p.i / Acknowledgement --- p.iii / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Rayleigh Fading Channels --- p.1 / Chapter 1.2 --- Wireless Ad Hoc Networks --- p.3 / Chapter 1.3 --- Ad Hoc Routing Protocols --- p.3 / Chapter 1.4 --- Information Capacity --- p.4 / Chapter 1.5 --- Cooperative Communications --- p.6 / Chapter 1.6 --- Outline of Thesis --- p.7 / Chapter 2 --- Background and Related Work --- p.8 / Chapter 2.1 --- Cooperative Communications --- p.8 / Chapter 2.1.1 --- Cooperative Diversity --- p.8 / Chapter 2.1.2 --- User Cooperation --- p.10 / Chapter 2.1.3 --- Coded Cooperation --- p.11 / Chapter 2.2 --- Cooperative Routing --- p.12 / Chapter 2.3 --- Information-Theoretic Study --- p.16 / Chapter 2.4 --- Optimization techniques --- p.17 / Chapter 3 --- Single-Source Single-Destination Cooperative Routing --- p.21 / Chapter 3.1 --- System Model --- p.22 / Chapter 3.1.1 --- Network Assumptions --- p.22 / Chapter 3.1.2 --- Routing Process --- p.22 / Chapter 3.1.3 --- Transmitting Signal --- p.23 / Chapter 3.1.4 --- Link Cost Formulation --- p.23 / Chapter 3.2 --- Minimum Energy Cooperative Route --- p.25 / Chapter 3.2.1 --- Cooperative Graph --- p.25 / Chapter 3.2.2 --- An Example of the Cooperative Graph --- p.27 / Chapter 3.2.3 --- Non-reducible property of the Cooperative Graph --- p.29 / Chapter 3.3 --- Optimized Scheduling --- p.32 / Chapter 3.3.1 --- KKT conditions --- p.32 / Chapter 3.3.2 --- Newton´ةs Method --- p.34 / Chapter 3.4 --- Complexity Analysis --- p.35 / Chapter 3.5 --- Simplified Scheduling Process --- p.37 / Chapter 3.5.1 --- Linear relationship in low rate regime --- p.37 / Chapter 3.5.2 --- The Simplified Scheduling Algorithm --- p.39 / Chapter 4 --- Heuristic Single-Source Cooperative Routing Schemes --- p.41 / Chapter 4.1 --- Maximum Hops Cut --- p.42 / Chapter 4.1.1 --- The Routing Protocol --- p.42 / Chapter 4.1.2 --- Simulations --- p.46 / Chapter 4.2 --- Maximum Relays Subgraph --- p.47 / Chapter 4.2.1 --- The Routing Protocol --- p.47 / Chapter 4.2.2 --- Simulations --- p.51 / Chapter 4.3 --- Adaptive Maximum Relays Subgraph --- p.55 / Chapter 4.3.1 --- The Routing Protocol --- p.55 / Chapter 4.3.2 --- Simulations --- p.57 / Chapter 4.4 --- Comparison of three protocols --- p.60 / Chapter 4.4.1 --- Implementation --- p.60 / Chapter 4.4.2 --- Cooperative Performance --- p.60 / Chapter 4.5 --- Enhancement of the algorithms --- p.61 / Chapter 4.5.1 --- Conclusion --- p.63 / Chapter 5 --- Multiplexing Cooperative Routes in Multi-source Networks --- p.64 / Chapter 5.1 --- Problem Formation --- p.65 / Chapter 5.1.1 --- The Network Model --- p.65 / Chapter 5.1.2 --- Objective Aim --- p.65 / Chapter 5.1.3 --- Link Cost Formulation --- p.66 / Chapter 5.1.4 --- Time Sharing and Interference --- p.66 / Chapter 5.1.5 --- Multiple Sources Consideration --- p.67 / Chapter 5.2 --- Multi-Source Route-Multiplexing Protocols --- p.68 / Chapter 5.2.1 --- Full Combination with Interference (FCI) --- p.68 / Chapter 5.2.2 --- Full Combination with Time Sharing (FCTS) --- p.68 / Chapter 5.2.3 --- Selection Between Interference and Time Sharing (SBITS) --- p.69 / Chapter 5.2.4 --- Interference and time sharing combinations --- p.71 / Chapter 5.2.5 --- The Simplified Version for SBITS --- p.72 / Chapter 5.3 --- Stage Cost Calculation --- p.73 / Chapter 5.3.1 --- Total stage cost formation in the sub timeslot --- p.73 / Chapter 5.3.2 --- Total stage cost formulation in different routing protocols --- p.74 / Chapter 5.3.3 --- Multiplexing for non-uniform timeslot routes --- p.75 / Chapter 5.4 --- Simulation --- p.76 / Chapter 5.4.1 --- Simulation model --- p.76 / Chapter 5.4.2 --- Simulation detail --- p.77 / Chapter 5.4.3 --- Simulation evaluation --- p.78 / Chapter 6 --- Conclusion and Future Work --- p.83 / Chapter 6.1 --- Conclusion --- p.83 / Chapter 6.2 --- Future Work --- p.84 / Chapter 6.2.1 --- Multiple-Source System Optimal Route --- p.84 / Chapter 6.2.2 --- Better Relay-Selection Policy --- p.85 / Chapter 6.2.3 --- Single Optimization for Minimum Energy Cooperative Route --- p.85 / Chapter 6.2.4 --- Dynamic Programming for Minimum Energy Cooperative Route --- p.85 / Chapter 6.2.5 --- Min-Max Problem --- p.85 / Chapter 6.2.6 --- Distributed Algorithm --- p.86 / Chapter 6.2.7 --- Game Theory --- p.86 / Bibliography --- p.87

Cheung, Man Hon. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 89-94). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgement --- p.iii / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Rayleigh Fading Channels --- p.1 / Chapter 1.2 --- Ultra-Wideband (UWB) Communications --- p.2 / Chapter 1.2.1 --- Definition --- p.2 / Chapter 1.2.2 --- Characteristics --- p.3 / Chapter 1.2.3 --- UWB Signals --- p.4 / Chapter 1.2.4 --- Applications --- p.5 / Chapter 1.3 --- Cooperative Communications --- p.7 / Chapter 1.4 --- Outline of Thesis --- p.7 / Chapter 2 --- Background Study --- p.9 / Chapter 2.1 --- Interference-Aware Routing --- p.9 / Chapter 2.2 --- Routing in UWB Wireless Networks --- p.11 / Chapter 2.3 --- Cooperative Communications and Routing --- p.12 / Chapter 3 --- Cooperative Routing in Rayleigh Fading Channel --- p.15 / Chapter 3.1 --- System Model --- p.16 / Chapter 3.1.1 --- Transmitted Signal --- p.16 / Chapter 3.1.2 --- Received Signal and Maximal-Ratio Combining (MRC) --- p.16 / Chapter 3.1.3 --- Probability of Outage --- p.18 / Chapter 3.2 --- Cooperation Criteria and Power Distribution --- p.21 / Chapter 3.2.1 --- Optimal Power Distribution Ratio --- p.21 / Chapter 3.2.2 --- Near-Optimal Power Distribution Ratio β´ة --- p.21 / Chapter 3.2.3 --- Cooperation or Not? --- p.23 / Chapter 3.3 --- Performance Analysis and Evaluation --- p.26 / Chapter 3.3.1 --- 1D Poisson Random Network --- p.26 / Chapter 3.3.2 --- 2D Grid Network --- p.28 / Chapter 3.4 --- Cooperative Routing Algorithm --- p.32 / Chapter 3.4.1 --- Cooperative Routing Algorithm --- p.33 / Chapter 3.4.2 --- 2D Random Network --- p.35 / Chapter 4 --- UWB System Model and BER Expression --- p.37 / Chapter 4.1 --- Transmit Signal --- p.37 / Chapter 4.2 --- Channel Model --- p.39 / Chapter 4.3 --- Received Signal --- p.39 / Chapter 4.4 --- Rake Receiver with Maximal-Ratio Combining (MRC) --- p.41 / Chapter 4.5 --- BER in the presence of AWGN & MUI --- p.46 / Chapter 4.6 --- Rake Receivers --- p.47 / Chapter 4.7 --- Comparison of Simple Routing Algorithms in ID Network --- p.49 / Chapter 5 --- Interference-Aware Routing in UWB Wireless Networks --- p.57 / Chapter 5.1 --- Problem Formulation --- p.57 / Chapter 5.2 --- Optimal Interference-Aware Routing --- p.58 / Chapter 5.2.1 --- Link Cost --- p.58 / Chapter 5.2.2 --- Per-Hop BER Requirement and Scaling Effect --- p.59 / Chapter 5.2.3 --- Optimal Interference-Aware Routing --- p.61 / Chapter 5.3 --- Performance Evaluation --- p.64 / Chapter 6 --- Cooperative Routing in UWB Wireless Networks --- p.69 / Chapter 6.1 --- Two-Node Cooperative Communication --- p.69 / Chapter 6.1.1 --- Received Signal for Non-Cooperative Communication --- p.69 / Chapter 6.1.2 --- Received Signal for Two-Node Cooperative Communication --- p.70 / Chapter 6.1.3 --- Probability of Error --- p.71 / Chapter 6.2 --- Problem Formulation --- p.75 / Chapter 6.3 --- Cooperative Routing Algorithm --- p.77 / Chapter 6.4 --- Performance Evaluation --- p.80 / Chapter 7 --- Conclusion and Future Work --- p.85 / Chapter 7.1 --- Conclusion --- p.85 / Chapter 7.2 --- Future Work --- p.86 / Chapter 7.2.1 --- Distributed Algorithm --- p.87 / Chapter 7.2.2 --- Performance Analysis in Random Networks --- p.87 / Chapter 7.2.3 --- Cross-Layer Optimization --- p.87 / Chapter 7.2.4 --- Game Theory --- p.87 / Chapter 7.2.5 --- Other Variations in Cooperative Schemes --- p.88 / Bibliography --- p.89

Chan, Hing Pan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 107-109). / Abstracts in English and Chinese. / Chapter Chapter 1 - --- Introduction --- p.1 / Chapter Chapter 2 - --- Background --- p.3 / Chapter 2.1 --- IEEE 802.11 MAC Protocol --- p.3 / Chapter 2.2 --- Related Work --- p.5 / Chapter Chapter 3 - --- Design Principles --- p.8 / Chapter Chapter 4 - --- Load-Adaptive Transmission Scheduling --- p.11 / Chapter 4.1 --- Contention Period (CP) --- p.14 / Chapter 4.2 --- Service Period (SP) --- p.22 / Chapter Chapter 5 - --- Synchronization --- p.27 / Chapter 5.1 --- Slot Boundary Detection --- p.27 / Chapter 5.2 --- Period Boundary Detection --- p.29 / Chapter 5.3 --- Period Identification --- p.30 / Chapter 5.4 --- Exception Handling --- p.62 / Chapter Chapter 6 - --- Performance Analysis --- p.70 / Chapter Chapter 7 - --- Performance Evaluations --- p.73 / Chapter 7.1 --- Parameter Tuning --- p.75 / Chapter 7.2 --- CBR UDP Traffic --- p.82 / Chapter 7.3 --- TCP Traffic --- p.94 / Chapter 7.4 --- Performance in Multi-hop Networks --- p.101 / Chapter Chapter 8 - --- Conclusions --- p.105 / Bibliography --- p.107

Ip, Yin Ki. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 96-102). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgement --- p.iv / Chapter 1 --- Introduction --- p.1 / Chapter 2 --- Background Study --- p.6 / Chapter 2.1 --- DTN Reference Implementation Model --- p.7 / Chapter 2.2 --- DTN Applications --- p.9 / Chapter 2.3 --- Multiple-copy Routing Strategies --- p.11 / Chapter 2.4 --- Buffer Management Strategies --- p.12 / Chapter 2.5 --- Performance Modeling of Multiple-copy Routing --- p.14 / Chapter 2.6 --- Conclusion on Background Study --- p.18 / Chapter 3 --- DTN with Resource Constraints --- p.20 / Chapter 3.1 --- Introduction --- p.20 / Chapter 3.2 --- Related Work --- p.21 / Chapter 3.3 --- "System Model, Replication, Forwarding and Buffer Management Strategies" --- p.22 / Chapter 3.4 --- Performance Evaluation --- p.29 / Chapter 3.4.1 --- Analysis on single-message-delivery with unlimited network resource --- p.29 / Chapter 3.4.2 --- Simulation study on multi-message-delivery with limited resource constraint --- p.34 / Chapter 3.5 --- Conclusion on DTN with Resource Constraints --- p.39 / Chapter 4 --- Multiple-copy Routing in DTN with Heteroge- neous Node Types --- p.41 / Chapter 4.1 --- Introduction --- p.41 / Chapter 4.2 --- Related Work --- p.44 / Chapter 4.3 --- System Model --- p.44 / Chapter 4.4 --- Performance Modeling --- p.46 / Chapter 4.4.1 --- Continuous Time Markov Chain (CTMC) Model --- p.46 / Chapter 4.4.2 --- Fluid Flow Approximation (FFA) --- p.53 / Chapter 4.5 --- Conclusion on DTN with Node Heterogeneity --- p.73 / Chapter 5 --- Conclusion and Future Work --- p.75 / Chapter A --- Random Direction Mobility Model --- p.78 / Chapter A.1 --- Mean Inter-encounter Interval --- p.79 / Chapter A.2 --- Inter-encounter Interval Distribution --- p.86 / Chapter A.3 --- Concluding Remarks --- p.88 / Chapter B --- Additional Results by Fluid Flow Approximation and Moment Closure Methods --- p.92 / Bibliography --- p.96

Traditionally, on-chip network communication was achieved with shared medium networks where devices shared the transmission medium with only one device driving the network at a time. To avoid performance losses, it required a fast bus arbitration logic. However, a single shared bus has serious limitations with the heterogeneous and multi-core communication requirements of today's chip designs. Point-to-point or direct networks solved some of the scalability issues, but the use of routers and of rather complex algorithms to connect nodes during each cycle caused new bottlenecks. As technology scales, the on-chip physical interconnect presents an increasingly limiting factor for performance and energy consumption. Network-on-chip, an emerging interconnect paradigm, provide solutions to these interconnect and communication challenges. Motivated by future bottom-up self-assembled fabrication techniques, which are believed to produce largely unstructured interconnect fabrics in a very inexpensive way, the goal of this thesis is to explore the design trade-offs of such irregular, heterogeneous, and unreliable networks. The important measures we care about for our complex on-chip network models are the information transfer, congestion avoidance, throughput, and latency. We use two control parameters and a network model inspired by Watts and Strogatz's small-world network model to generate a large class of different networks. We then evaluate their cost and performance and introduce a function which allows us to systematically explore the trade-offs between cost and performance depending on the designer's requirement. We further evaluate these networks under different traffic conditions and introduce an adaptive and topology-agnostic ant routing algorithm that does not require any global control and avoids network congestion.

In the late 1990s a number of law firms and other organisations began to market online products which &quotpackage&quot legal knowledge. Unlike spreadsheets, word processing software and email, these products are not designed to provide efficiency improvements. Rather, online legal knowledge products, which package and apply the law, were and are viewed by many as having the potential to make major changes to legal practice. Many used the term &quitrevolution&quot to describe the anticipated impact. Like any new technology development, many intersecting factors contributed to their development. In many ways they built on existing uses of technology in legal practice. The various information technology paradigms which underpin them - text retrieval, expert systems/artificial intelligence, document automation, computer aided instruction (CAI) and hypertext - were already a part of the &quotcomputerisation of law&quot. What is new about online legal knowledge products is that as well as using technology paradigms such as expert systems or document automation to package and apply the law, they are developed using browser-based technologies. In this way they leverage the comparative ease of development and distribution capabilities of the Internet (and/or intranets). There has been particular interest in the impact of online legal knowledge products on the legal services provided to large commercial organisations. With the increasing burden of corporate compliance, expanding role of the in-house lawyer and pressure to curb costs, online legal knowledge products should flourish in commercial organisations and many have been adamant that they will. However, there is no convincing evidence that anything like a &quotrevolution&quot has taken place. Success stories are few and far between. Surprisingly few have asked whether this &quotrevolution&quot has failed, or seriously analysed whether it lies ahead. If it does lie ahead, what factors, if any, need to taken into account in order for it to take place? If there is to be no revolution, what value should be placed on online legal knowledge products? In this dissertation I use the findings of my own empirical work, supported by a literature survey, to demonstrate that the impact of online legal knowledge products has been modest. I argue that in order to build successful online legal knowledge products it is necessary to appreciate that a complex system of interacting factors underpins their development and use,and address those factors. I propose a schematic representation of the relationships involved in producing an online legal knowledge product and use the findings of some empirical work, together with a review the literature in related fields, to identify the factors relevant to the various components of this framework. While there are many interacting factors at play, four sets of considerations emerge from my research as particularly important: integrating different technology paradigms, knowledge acquisition, usability, and implementation. As a practical matter, the implication of these findings is that some online legal knowledge products are more likely to be successful than others, and that there are other technology applications that may represent a better investment of the limited in-house technology budget than many online legal knowledge products. I also argue that while most of the challenges involved in integrating different technology paradigms, improving usability, and effective implementation can be addressed with varying levels of effort, the problem of the knowledge acquisition bottleneck is intractable. New approaches to knowledge acquisition are required to overcome the knowledge acquisition bottleneck. I identify some potential approaches that emerge from my research: automation, collaboration and coalition, phasing and simple solutions.