Today's electric power system is operated under increasingly stressed conditions. As electrical demand increases, the existing grid is operated closer to its stable operating limits while maintaining high reliability of electric power delivery to its customers. Protective schemes are designed to account for pressures towards unstable operation, but there is always a tradeoff between security and dependability of this protection. Adaptive relaying schemes that can change or modify their operation based on prevailing system conditions are an example of a protective scheme increasing reliability of the power system. The purpose of this thesis is to validate and analyze implementation of the Security-Dependability Adaptive Voting Scheme. It is demonstrated that this scheme can be implemented with a select few Phasor Measurement Units (PMUs) reporting positive sequence currents to a Phasor Data Concentrator (PDC). At the PDC, the state of the power system is defined as Stressed or Safe and a set of relays either vote or perform normal operation, respectively. The Adaptive Voting Scheme was implemented using two configurations: hardware- and software-based PDC solutions. Each was shown to be functional, effective, and practical for implementation. Practicality was based on the latency of Wide Area Measurement (WAM) devices and the added latency of relay voting operation during Stressed conditions. Phasor Measurement Units (PMUs), Phasor Data Concentrators (PDCs), and relay operation delays were quantified to determine the benefits and limitations of WAMS protection and implementation of the voting scheme. It is proposed that the delays injected into the existing protection schemes would have minimal effect on the voting scheme but must be accounted for when implementing power system controls due to the real-time requirements of the data. / Master of Science

Living in an increasingly networked world, with an abundant number of services available to consumers, the consumer electronics market is enjoying a boom. The average consumer in the developed world may own several networked devices such as games consoles, mobile phones, PDAs, laptops and desktops, wireless picture frames and printers to name but a few. With this growing number of networked devices comes a growing demand for services, defined here as functions requested by a client and provided by a networked node. For example, a client may wish to download and share music or pictures, find and use printer services, or lookup information (e.g. train times, cinema bookings). It is notable that a significant proportion of networked devices are now mobile. Mobile devices introduce a new dynamic to the service discovery problem, such as lower battery and processing power and more expensive bandwidth. Device owners expect to access services not only in their immediate proximity, but further afield (e.g. in their homes and offices). Solving these problems is the focus of this research. This Thesis offers two alternative approaches to service discovery in Wide Area Networks (WANs). Firstly, a unique combination of the Session Initiation Protocol (SIP) and the OSGi middleware technology is presented to provide both mobility and service discovery capability in WANs. Through experimentation, this technique is shown to be successful where the number of operating domains is small, but it does not scale well. To address the issue of scalability, this Thesis proposes the use of Peer-to-Peer (P2P) service overlays as a medium for service discovery in WANs. To confirm that P2P overlays can in fact support service discovery, a technique to utilise the Distributed Hash Table (DHT) functionality of distributed systems is used to store and retrieve service advertisements. Through simulation, this is shown to be both a scalable and a flexible service discovery technique. However, the problems associated with P2P networks with respect to efficiency are well documented. In a novel approach to reduce messaging costs in P2P networks, multi-destination multicast is used. Two well known P2P overlays are extended using the Explicit Multi-Unicast (XCAST) protocol. The resulting analysis of this extension provides a strong argument for multiple P2P maintenance algorithms co-existing in a single P2P overlay to provide adaptable performance. A novel multi-tier P2P overlay system is presented, which is tailored for service rich mobile devices and which provides an efficient platform for service discovery.

Software-Defined Wide Area Networks is a technology that has received a lot of attention in recent years. The technology enables direct Internet access without having to direct traffic through a data center. It also enables the use of less expensive Internet connections to build the Wide-Area Network, expensive Multiprotocol LabelSwitchingconnectionsarenolongernecessary. This results in greater responsibility for enterprises when it comes to ensuring performance within the network, where the previous dedicated links with a guaranteed performance by Internet Service Provider have been replaced with unpredictable best-effort connections. The project targets the challenges Software-Defined Wide Area Networks introduces in terms of monitoring, by examining the required network transparency between Wide-Area Network edges. A selection of Network Management Systems was evaluated with the requirements specification as a basis. The results show that more diligent monitoring at the edges is needed. Visibility into the underlay network, providing transportation, has to be available. Where the enterprises need to be able to examine path-selection of traffic per application. To ensure that the root of problems can be located in case of performance issues. This was not obtained by the evaluated Network Management Systems. Moreover, it turned out that there was no common standard available for monitoring the technology at the time of the project. The lack of knowledge in the field aimed to decrease with the degree project and the result is of greatest interest to companies that have made the transition to Software-Defined Wide Area Networks or are about to do so. / Software-Defined Wide Area Networks är en teknik som har fått mycket uppmärksamhet de senaste åren. Tekniken möjliggör direkt internetåtkomst utan att behöva dirigera trafik genom datacentret. Det möjliggör också användningavbilligareinternetanslutningar för att bygga Wide-AreaNetwork, dyra Multiprotocol Label Switching anslutningar är inte längre nödvändiga. Detta resulterar i ett större ansvar för företag när det gäller att säkerställa prestanda inom nätverket, där de tidigare dedikerade länkarna med garanterad prestanda av internetleverantörer har ersatts med oförutsägbara anslutningar som skickar trafik efter bästa förmåga. Examensarbetet riktar sig mot de utmaningar som Software-Defined Wide Area Networks innebär när det gäller övervakning, genom att undersöka den nödvändiga nätverkstransparensen mellan Wide-Area Network kanterna. Ett urval av nätverkshanteringssystem utvärderades med en definierad kravspecifikation som grund. Resultaten visar att det behövs mer noggrann övervakning i Wide-Area Network kanterna. Insyn i transportlagret måste vara tillgänglig och företagen behöver kunna granska vägval av trafik per applikation, för att säkerställa att ursprungsfel går att lokaliseras i händelse av prestandaproblem. Detta erhölls inte av de utvärderade nätverkshanteringssystemen. Det visade sig dessutom att det inte fanns någon gemensam standard tillgänglig för övervakning av tekniken vid tidpunkten för examensarbetet. Examensarbetet syftar till att minska kunskapsbristen inom området och resultatet är av störst intresse för företag som gjort övergången till Software-Defined Wide Area Networks eller är på väg att göra det.

ITC/USA 2006 Conference Proceedings / The Forty-Second Annual International Telemetering Conference and Technical Exhibition / October 23-26, 2006 / Town and Country Resort & Convention Center, San Diego, California / The Central Test and Evaluation Investment Program (CTEIP) Integrated Network Enhanced Telemetry (iNET) program is currently testing a wireless local area networking (WLAN) in an L-band telemetry (TM) channel to evaluate the feasibility and capabilities of enhancing traditional TM methods in a seamless wide area network (WAN). Several advantages of networking are real-time command and control of instrumentation formats, quick-look acquisition, data retransmission and recovery (gapless TM) and test point real-time verification. These networking functions, and all others, need to be tested and evaluated. The iNET team is developing a WLAN based on 802.x technologies to test the feasibility of the enhanced telemetry implementation for flight testing.

Approved for public release; distribution is unlimited. / The purpose of this thesis is to discuss the new features and enhancements of Windows Server 2003. Windows NT and Windows 2000 were known to have numerous security vulnerabilities; hence Microsoft focused on improving security by making Windows Server 2003 "secure by design, secure by default, secure in deployment." This thesis examines the differences between the five unique editions of the Windows Server 2003 family. Some of the pros and cons of migrating to Windows Server 2003 are highlighted. The author hopes this study will assist information technology professionals with their decision on whether or not to upgrade to this latest version of Microsoft's flagship network operating system. / Lieutenant Commander, United States Navy

M.Comm. / This study was conducted with the intent of understanding and evaluating the commercial use and possibilities that the Internet offers, as well as the strategic approach businesses should take when commencing with electronic commerce on the Internet. The potential value of Intranets and Extranets has also been examined briefly. The Internet is a very useful mechanism for marketing as well as sales of products or services on a domestic or international basis. Various other commercial possibilities and uses exist for the Internet, as well as for its derivatives — the Intranet and Extranet. In the fiercely competitive market of today, companies research, develop and invest resources in various methods and tools in the hope to gain competitive advantage over their rivals. The Internet, Intranet and Extranet, used in isolation or conjunction, pose an extremely attractive alternative to gaining competitive advantage in a specific sector or market niche.The success of the Internet as a business tool depends directly on the overall business strategy that is driving the approach. For optimum success the main business strategy must be aligned with the Information Technology Strategy, and especially include thorough consideration as well as planning when implementing the Internet or one of its derivatives as a business tool.

Submitted by PPG Engenharia El?trica (engenharia.pg.eletrica@pucrs.br) on 2018-06-08T13:54:41Z No. of bitstreams: 1 RICARDO_VINICIUS_DOTH_DIS.pdf: 9281309 bytes, checksum: d26fbf7274d4c8eb7158a2d987437b1b (MD5) / Approved for entry into archive by Sheila Dias (sheila.dias@pucrs.br) on 2018-06-18T12:49:23Z (GMT) No. of bitstreams: 1 RICARDO_VINICIUS_DOTH_DIS.pdf: 9281309 bytes, checksum: d26fbf7274d4c8eb7158a2d987437b1b (MD5) / Made available in DSpace on 2018-06-18T12:58:59Z (GMT). No. of bitstreams: 1 RICARDO_VINICIUS_DOTH_DIS.pdf: 9281309 bytes, checksum: d26fbf7274d4c8eb7158a2d987437b1b (MD5) Previous issue date: 2018-03-27 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Wide Area Motion Imagery (WAMI) systems acquire large area aerial images in real time to provide accurate situational awareness information from a region (BLASCH et al., 2014). This system is applied for urban aerial monitoring. Unfavorable environmental conditions, such as shadow regions, are factors that increase system complexity by compromising the effectiveness of tracking algorithms and human visual interpretation (PORTER; FRASER; HUSH, 2010). Several techniques of shadow removal in aerial images have been developed, however due to the characteristics of the shadow and aerial image, a specific method to evaluate and compare the removal is unknown. The main objective of this study is to develop a method to evaluate shadow removal algorithms in aerial images acquired by the WAMI system. This work proposes a radiometric approach modifying the illumination in a controlled environment, simulating an aerial scene, acquiring images with and without the presence of shadows. The image with shadows is processed by the evaluated shadow removal algorithm, with the ideal output being the shadow free image. Shadow detection is evaluated using the confusion matrix concept. Shadow removal is evaluated using the structural similarity index (SSIM). As a result the reduced scale aerial scene model is presented to generate shadow and freeshadow images and the evaluation of 3 shadow removal methods using the data sets of images obtained from the scale model applying the methodology developed. / Sistemas WAMI (Wide Area Motion Imagery) adquirem imagens a?reas de grandes ?reas em tempo real para prover informa??es precisas de uma determinada regi?o (BLASCH et al., 2014). Este sistema ? aplicado para monitoramento a?reo urbano. Condi??es ambientais desfavor?veis, como ?reas sombreadas, s?o fatores que aumentam a complexidade do sistema comprometendo a efic?cia de algoritmos de rastreamento e a interpreta??o visual humana (PORTER; FRASER; HUSH, 2010). Diversas t?cnicas de remo??o de sombra em imagens a?reas foram desenvolvidas, no entanto devido ?s caracter?sticas da sombra e da imagem a?rea ? desconhecido um m?todo espec?fico para avaliar e comparar a remo??o de sombras em imagens a?reas. O objetivo principal deste estudo ? desenvolver um m?todo para avaliar algoritmos de remo??o de sombra em imagens a?reas adquiridas pelo sistema WAMI. Este trabalho prop?e uma abordagem radiom?trica modificando a ilumina??o em um ambiente controlado, simulando uma cena a?rea, adquirindo imagens com e sem sombras. A imagem com sombra ? processada pelo algoritmo de remo??o de sombra avaliado, sendo a imagem sem sombra o resultado ideal a ser alcan?ado. A detec??o de sombra ? avaliada utilizando o conceito de matriz de confus?o (error matrix). A remo??o de sombra ? avaliada utilizando o ?ndice de similaridade estrutural entre duas imagens (SSIM). Foram desenvolvidos o modelo de cena a?rea em escala reduzida para gerar imagens com e sem sombra e a avalia??o de 3 m?todos de remo??o de sombras utilizando os data sets de imagens obtidas do modelo em escala aplicando a metodologia descrita.

Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references (p. 105-111).

Accelerated by on-demand computing, the number and diversity of the Internet services is increasing. Such online services often have unique requirements for the underlying wide-area network: For instance, online gaming service might benefit from low delay and jitter paths to client, while online data backup service might benefit from cheaper paths. Unfortunately, today's Internet does not accommodate fine-grained, service-specific wide-area route control. In this dissertation, I achieve the following goals: 1) improve the access to the routes, 2) quantify the benefits of fine-grained route control, and 3) evaluate the efficiency of current payment schemes for the wide-area routes. * Improving access to wide-area route control. Online services face significant technological and procedural hurdles in accessing the routes: Each service in need to control the Internet routes, has to obtain own equipment, Internet numbered resources, and establish contracts with upstream ISPs. In this dissertation, I propose and describe implementation and deployment of a secure and scalable system which provides on-demand access to the Internet routes. In setting such as cloud data center, the system can support multiple online services, providing each service with an illusion of direct connectivity to the neighboring Internet networks, which, for all practical purposes, allows services to participate fully in the Internet routing. * Quantifying the benefits of fine-grained route control. Even if online services are presented with wide-area route choice, it is not clear how much tangible benefit such choice provides. Most modern Online Service Providers (OSP) rely primarily on the content routing to improve network performance between the clients and the replicas. In this dissertation, I quantify the potential benefit the OSPs can gain if they perform a joint network and content routing. Among other findings, I find that by performing joint content and network routing, OSPs can achieve 22% larger latency reduction than can be obtained by content routing alone. * Modeling and evaluating the efficiency of the current payment schemes for wide-area routes. Finally, increasing diversity and sophistication of the online services participating in the Internet routing poses a challenge to payment models used in today's Internet. Service providers today charge business customers a blended rate: a single, "average" price for unit of bandwidth, without regard to cost or value of individual customer's flows. In my dissertation, I set to understand how efficient this payment model is and if more granular payment model, accounting for the cost and value of different flows could increase the ISP profit and the consumer surplus. I develop an econometric demand and cost model and map three real-world ISP data sets to it. I find that ISPs can indeed improve the economic efficiency with just a few pricing tiers.

Thesis (M.Eng.Sc.)--University of Adelaide, Dept. of Electrical and Electronic Engineering, 2001. / Bibliography: leaves 128-135.