Voice Over IP (VoIP) telephony is becoming widespread, and is often integrated into computer networks. Because of his, it is likely that malicious software will threaten VoIP systems the same way traditional computer systems have been attacked by viruses, worms, and other automated agents. While most users have become familiar with email spam and viruses in email attachments, spam and malicious traffic over telephony currently is a relatively unknown threat. VoIP networks are a challenge to secure against such malware as much of the network intelligence is focused on the edge devices and access environment. A novel security architecture is being developed which improves the security of a large VoIP network with many inexperienced users, such as non-IT office workers or telecommunication service customers. The new architecture establishes interaction between the VoIP backend and the end users, thus providing information about ongoing and unknown attacks to all users. An evaluation of the effectiveness and performance of different implementations of this architecture is done using virtual machines and network simulation software to emulate vulnerable clients and servers through providing apparent attack vectors.

Approved for public release, distribution is unlimited / Converging voice and data networks has the potential to save money and is the main reason Voice over Internet Protocol (VoIP) is quickly becoming mainstream in corporate America. The potential VoIP offers to more efficiently utilize the limited connectivity available to ships at sea makes it an attractive option for the Navy. This thesis investigates the usefulness of VoIP for the communications needs of a unit level ship. This investigation begins with a review of what VoIP is and then examines the ship to shore connectivity for a typical unit level ship. An OMNeT++ model was developed and used to examine the issues that affect implementing VoIP over this type of link and the results are presented. / Lieutenant Commander, United States Navy

-- The advent of Internet, the phone mobile and the globalization have modified the forms of communication in the world and the enterprises in general. All this has brought the search of facilities of communications permanents, mobilities and secures with quality of service to improve the Internet and the new aplications on devices mobile. The studies of the new protocol of internet as Ipv6 are in a proces that consist in finding new focus to improve the quality of service. This thesis consists in analyzing and give recomendations of Ipv6 with Business Intelligence to demonstrate that the use improve the management in the enterprises. Ipv6 is the best solution to improve the throughput in the network. The other side, it proposes a new way of business on internet y the born the new aplications as for example the m-commerce and Business Intelligence since any devices mobile. / Determinar el grado de influencia que el Business Intelligence bajo plataforma IP versión6 ejerce en la Gestión empresarial. Además de realizar un analisis de IPv6 sobre redes inalámbricas y su desempeño con las aplicaciones que permiten el acceso a la información. Comparativos entre los protocolos IPv4 y/o IPv6. En base a estos estudios, se proponen una serie de recomendaciones para el modelado de aplicaciones, mismas que ayudan a obtener un mejor desempeño de ellas sobre las redes alámbricas e inalámbricas. Su enfoque está enmarcado en la importancia de la consecución, análisis y difusión de la información para producir inteligencia que ayude a las empresas en la toma de mejores decisiones, aunado a todo ello el avance tecnológico y la revolución de la redes de hoy y ello se obtiene con el aporte del Ipv6. / Determinar el grado de influencia que el Business Intelligence bajo plataforma IP versión6 ejerce en la Gestión empresarial. Además de realizar un analisis de IPv6 sobre redes inalámbricas y su desempeño con las aplicaciones que permiten el acceso a la información. Comparativos entre los protocolos IPv4 y/o IPv6. En base a estos estudios, se proponen una serie de recomendaciones para el modelado de aplicaciones, mismas que ayudan a obtener un mejor desempeño de ellas sobre las redes alámbricas e inalámbricas. Su enfoque está enmarcado en la importancia de la consecución, análisis y difusión de la información para producir inteligencia que ayude a las empresas en la toma de mejores decisiones, aunado a todo ello el avance tecnológico y la revolución de la redes de hoy y ello se obtiene con el aporte del Ipv6.

Les retours et les études dont on dispose sur les réseaux IP par satellite ne permettent pas d’apprécier les performances dont ils sont capables. Pourtant, les difficultés de transmettre de l’IP par satellite persistent encore. L’inadaptation du protocole IP, initialement conçu pour des réseaux terrestres, au large produit délai-bande du média satellite est une raison. Le fonctionnement souvent dé-corrélé entre les niveaux supérieurs de la pile TCP/IP et les couches physique et MAC du média satellite, est une autre. Dans le cadre de ce travail de thèse nous adoptons une démarche expérimentale basée sur l’observation, l’analyse et l’évaluation de systèmes implantant des technologies IP par satellite tels que le standard DVB-RCS, la technologie propriétaire iDirect ou la nouvelle norme DVB-S2. Nous étudions l’impact des règles de qualité de service IP sur les performances des applications dans un contexte de bande limitée. Nous nous penchons notamment sur l’évaluation des efficacités de l’encapsulation IP en termes de consommation de bande. Notre premier objectif est de déceler les niveaux auxquels un opérateur peut agir en vue d’optimiser la configuration d’un système IP par satellite et en accroître les performances / Despite of a number of IP satellite networks developed and deployed, only a limited number of studies and feedbacks about the performance is available. IP over satellite systems raises several constraints. One of the main reasons is the lack of adaptation of IP protocol, initially designed for terrestrial wired networks, to the large bandwidth delay product of the satellite media. Another reason is a lack of coordination between the IP protocol stack upper layer and the satellite MAC and physical layer. The purpose of this PhD study is to evaluate and assess the behaviour of IP applications when conveyed over satellite systems. We mainly focus on the IP quality of service performance, bandwidth encapsulation efficiency as well as IP applications metrics. Through the observation, we try to find how it’s possible to modify the IP satellite systems configuration in order to improve IP applications performance. We also suggest some ideas about the way to refine these technologies with regards to the design aspects. Experimentations have been performed over test beds implementing both standardised satellite technologies such as DVB-RCS as well as proprietary systems such as iDirect in addition to the new normalised technology DVB-S2

Approved for public release, distribution is unlimited / Internet Protocol version six (IPv6), the next generation Internet Protocol, exists sparsely in today's world. However, as it gains popularity, it will grow into a vital part of the Internet and communications technology in general. Many large organizations, including the Department of Defense, are working toward deploying IPv6 in many varied applications. This thesis focuses on the design and implementation issues that accompany a migration from Internet Protocol version four (IPv4) to IPv6 in the Monterey Security Enhanced Architecture (MYSEA). The research for this thesis consists of two major parts: a functional comparison between the IPv6 and IPv4 designs, and a prototype implementation of MYSEA with IPv6. The current MYSEA prototype relies on a subset of Network Address Translation (NAT) functionality to support the network's operation; and, due to the fact that IPv6 has no native support for NAT, this work also requires the creation of a similar mechanism for IPv6. This thesis provides a preliminary examination of IPv6 in MYSEA, which is a necessary step in determining whether the new protocol will assist with or detract from the enforcement of MYSEA policies. / Ensign, United States Navy

A relação entre o Grau de Internacionalização (GI) e o desempenho das empresas multinacionais (EMNs) tem sido amplamente estudada na literatura de negócios internacionais. Entretanto, a maior parte dos estudos é realizada com empresas dos países desenvolvidos. De modo a contribuir com o desenvolvimento da teoria de internacionalização-desempenho, o presente estudo analisou essa relação no universo das EMNs de economias em desenvolvimento: Brasil, Rússia, Índia, China e África do Sul (BRICS). O principal objetivo do trabalho foi analisar se a estratégia de expansão internacional dessas EMNs está sendo traduzida em forma de eficiência e eficácia na gestão do negócio da empresa. O modelo hipotético do trabalho considera duas variáveis moderadoras da relação internacionalizaçãodesempenho: (1) Folga Organizacional (FO); e (2) Intensidade de Pesquisa e Desenvolvimento (IP&D). A amostra do estudo corresponde a 219 EMNs dos países integrantes dos BRICS, sendo que as informações levantadas referem-se a um período de 9 anos (2002-2010), totalizando 834 pares de observações para cada variável presente no modelo. Os dados foram obtidos junto a duas fontes: (1) Compustat Data; e (2) Thomson One. Após análises de regressão múltipla, utilizando o método dos Mínimos Quadrados Ordinários (MQO), verificou-se uma relação não linear quadrática em forma de \"U\" entre o grau de internacionalização e o desempenho das EMNs dos países integrantes dos BRICS. Adicionalmente, os resultados mostram um positivo e significante efeito moderador da FO sobre a relação internacionalização-desempenho, entretanto, o mesmo não se verificou para a IP&D. Duas importantes implicações deste estudo para os gestores de negócios internacionais nas regiões dos BRICS é que: (1) os benefícios da expansão internacional não surgem de uma hora pra outra, mas exigem paciência para serem alcançados; (2) os gestores devem enxergar a FO como uma ferramenta estratégica de atuação no contexto internacional. Com base nos resultados encontrados, implicações e indicações para futuras pesquisas são fornecidas. / The relationship between the degree of internationalization and performance of multinational companies (MNCs) has been widely studied in the literature of international business. However, most studies are conducted with companies from developed countries. In order to contribute to the development of the theory of internationalization-performance, this study examined this relationship in the universe of MNCs in developing economies: Brazil, Russia, India, China and South Africa (BRICS). The main objective of this study was to analyze the strategy of international expansion of these MNCs is being translated in the form of efficiency and effectiveness in managing the company\'s business. The hypothetical model of the work considers two moderating variables of internationalization-performance relationship: (1) Organizational Slack (OS); and (2) Research and Development Intensity (R&DI). Sample corresponds 219 MNCs from BRICS countries, and collected data refers to 2002-2010 period, totaling 834 pairs of observations for each variable in the model. Data were obtained from two sources: (1) Compustat Data; and (2) Thomson One. Multiple regression analysis, using Ordinary Least Squares (OLS) method, showed a U-Shaped curvilinear relationship between the degree of internationalization and performance in MNCs from BRICS countries. Additionally, results show a positive and significant moderating effect of FO on internationalization-performance relationship, however, the same was not true for R&DI. Two important implications of this study for managers of international business in the regions of the BRICS is that: (1) the benefits from international expansion require patience to achieve; and (2) managers must see FO as strategic tool for performance in an international context. Based on the findings, implications and directions for future research are provided.

A expansão do tecido urbano e o adensamento das cidades têm um impacto negativo sobre os recursos hídricos, tanto na quantidade quanto na qualidade das águas no ambiente, pois aumenta as cargas de poluentes no meio e altera o ciclo hidrológico natural, criando riscos à população. É possível reduzir tais riscos através do diagnóstico, planejamento e gestão adequada das áreas de risco para a proteção civil e das comunidades. A abordagem ecohidrológica, que considera a relação funcional entre hidrologia, sistemas aquáticos e sua biota na escala de bacia hidrográfica, incorporando aspectos quantitativos e qualitativos da água em uma visão de interdependência entre Ecologia e Hidrologia, permite o diagnóstico, planejamento e manejo adequado dos cursos hídricos em benefício tanto dos humanos quando dos demais seres vivos. Este trabalho busca investigar a dinâmica ecohidrológica no espaço e no tempo da Bacia do Rio Monjolinho, localizada no Município de São Carlos (SP), no contexto de gestão de riscos de desastres hidrológicos. Os processos quantitativos são investigados por meio de simulações com o SWMM (Storm Water Management Model) e os dados de simulação são utilizados, por vez, na determinação do IP (Índice de Perigo) de pontos estratégicos da bacia hidrográfica e também das áreas com maior risco de inundação. Com relação à qualidade, onze variáveis clássicas de qualidade dágua são determinadas experimentalmente em 15 pontos da bacia a fim de caracterizar a dinâmica das cargas de poluentes, permitindo desta maneira a avaliação do risco biológico na bacia. Os resultados quali-quantitativos mostram que os vales dos rios oferecem riscos tanto devido às inundações quanto devido ao alto risco de contaminação. / The urban tissue expansion and the urban area densification have a negative impact on water resources, in terms of quality and quantity of available water, since it increases the polutant load at the same time it changes the natural hydrological cycle, exposing population to risk. It is possible to reduce the risks by means of assessment, planning and correct management of risk areas in order to protect the communities. The ecohydrology, which takes into account the functional relationship between hydrology, aquatic systems and biota in watershed scale, considering quali-quantitative aspects and their interdependecies, enable us to assess, plan and manage risks in an advantageous way for humans and living beings as well. This work investigates the ecohydrology dynamics in space and time of Rio Monjolinho basin, located within the municipality of São Carlos (SP), Brazil, in the context of disaster risk management. The quantitative aspects are investigated using the SWMM (Storm Water Management Model) simulation model, and the simulation data generated are used to calculate the Risk Index (RI) and to map the flooding risk areas in the basin. Eleven classic water quality variables are experimentaly determined to assess the polutant load dynamics and its distribution in the sub-basins, enabling us to assess the biologic risks. The results show that some areas in the catchment are not just flood risk areas but also areas of high biological risk of contamination.

El presente trabajo analiza los principales y más básicos componentes que actúan en un Sistema de Transporte Inteligente, de tal manera que se diseñe una infraestructura de red capaz de transmitir la información, recogida de las vías, que necesitan los operadores del tránsito, y poder así controlar mejor el transporte urbano. / Tesis

La aparición de nuevas tecnologías en las redes de datos, han dado origen a modelos de red que brindan elevados índices de calidad y nuevas prestaciones a los clientes. Entre estos nuevos modelos se tiene a la Red IP, la cual es una red de transmisión de datos basada en el uso del protocolo IP (Internet Protocol) ampliamente difundido en Internet. La red IP esta físicamente implementada con equipos ruteadores, nodos conmutadores, servidores y aplicaciones de software, orientada a dar conectividad a las redes y computadoras que trabajan bajo este protocolo. El núcleo de la red esta formado por una malla ATM de alto rendimiento, la cual brinda el transporte de los paquetes IP entre los diferentes nodos de acceso. Actualmente las plataformas de gestión de tráfico y la de operación y mantenimiento centralizado de las centrales telefónicas de conmutación digital a nivel nacional están basadas en conexiones X.25 a cada una de las centrales. Estas conexiones dedicadas generan altos costos de alquiler, operación y mantenimiento para la administración. El presente trabajo tiene como objetivo usar la Red IP como medio de transporte para una red de conmutación de paquetes X.25 utilizada por las plataformas de gestión y mantenimiento centralizado para la conexión a las centrales telefónicas de conmutación digital. Lo que se va a diseñar es una solución que va a reemplazar el medio de transporte de la red X.25 por un medio de transporte IP. Este trabajo se divide en dos partes principales: En la Primera Parte se hace un breve marco teórico sobre la Redes X.25 e IP, también se presenta como esta estructurada e implementada la Red IP en el Perú, luego se explica en detalle como están conformadas y cual es la función dentro de la administración de las plataformas de Gestión de Tráfico (SGT) y la de Operación y Mantenimiento Centralizado (EOC). / Tesis

La presente Tesis consiste en brindar una propuesta técnica para la migración del core de la red NGN de una operadora implementada en IP hacia IP/MPLS. Durante el desarrollo de este proyecto se presenta el marco teórico de las redes NGN y se realiza la comparación entre las tecnologías IP y MPLS con el objetivo de observar las ventajas que presenta MPLS al brindar QoS. Luego, se presenta la Propuesta de migración en la cual se presenta el escenario inicial así como los aspectos técnicos, plan de trabajo y el escenario final de la migración. Por último, se detallan las conclusiones obtenidas al final de este proyecto, recomendaciones y trabajos futuros. / Tesis