The development of electronic commerce (e-commerce) is the most visible business use of the World Wide Web. The primary goal of an e-commerce site is to sell goods and services online. This project deals with developing an e-commerce platform for marginalized communities of the Eastern Cape region, South Africa. An online “shopping mall” to support the marketing of art and crafts from disadvantaged communities is presented, with Linux-Apache-MySQL-PHP (LAMP) as the development environment. Free and Open Source Software has been chosen to develop the virtual shopping mall system because the use of Open Source allows easy localization and extensions to the system developed and long term sustainability, as the source code is available. Also, it might start a “virtuous” circle, whereby young members of the communities hosting art and craft makers become involved in maintenance, and then production, of software systems. One important design constraint from the e-commerce platform presented in this thesis is the possibility for the art and craft makers to manage their shops directly, from the initial loading of their wares to the day-to-day maintenance, such as changes of price or items. The user requirement elicitation and initial field testing were conducted in Dwesa, an area on the wild coast, South Africa. The system currently comprising two shops is live at the time of writing this thesis at www.dwesa.com.

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The purpose of this project was to explore the use of Web services to solve enterprise computing problems. XML-based Web services allow complex information systems to be subdivided. In order to explore this architectural paradigm, two systems were built: an employee records sytem, and a vacation system.

Multihoming allows nodes to be multiply connected to the network. It forms the basis of features which can improve network responsiveness and robustness; e.g. load balancing and fail-over, which can be considered as a choice between network locations. However, IP today assumes that IP addresses specify both network location and node identity. Therefore, these features must be implemented at routers. This dissertation considers an alternative based on the multihoming approach of the Identifier Locator Network Protocol (ILNP). ILNP is one of many proposals for a split between network location and node identity. However, unlike other proposals, ILNP removes the use of IP addresses as they are used today. To date, ILNP has not been implemented within an operating system stack. I produce the first implementation of ILNP in FreeBSD, based on a superset of IPv6 – ILNPv6 – and demonstrate a key feature of ILNP: multihoming as a first class function of the operating system, rather than being implemented as a routing function as it is today. To evaluate the multihoming capability, I demonstrate one important application of multihoming – load distribution – at three levels of network hierarchy including individual hosts, a singleton Site Border Router (SBR), and a novel, dynamically instantiated, distributed SBR (dSBR). For each level, I present empirical results from a hardware testbed; metrics include latency, throughput, loss and reordering. I compare performance with unmodified IPv6 and NPTv6. Finally, I evaluate the feasibility of dSBR-ILNPv6 as an alternative to existing multihoming approaches, based on measurements of the dSBR's responsiveness to changes in site connectivity. We find that multihoming can be implemented by individual hosts and/or SBRs, without requiring additional routing state as is the case today, and without any significant additional load or overhead compared to unicast IPv6.

Indiana University-Purdue University Indianapolis (IUPUI) / The study of this thesis is focused on reducing the link failure detection time in OSPF network. When a link failure occurs, OSPF protocol detects it using RouterDeadInterval time. This timer is fired only after a predefined time interval, thus increasing the time of convergence after the link failure. There are previous studies to reduce the RouterDeadInterval time, but they introduce other effects which are discussed later in the thesis. So, a novel approach is proposed in this thesis to reduce the link failure detection time with the help of emerging network architecture Software Defined Networking (SDN) and OpenFlow Protocol.

The field buses, and particularly the ‘PROFIBUS’, are currently widely used in automation systems, with the intention to automate industrial applications. It is of the utmost importance that one should understand how these systems operate, because failure to understand may result in improper applications, which can ultimately lead to intense network problems and, consequently, lead to potential catastrophic failures in industrial equipment, as well as compromising the health and safety of the people. This research was the performance evaluation of SAMANCOR PROFIBUS network that controls the chrome manufacturing plant. The problem with the network was that it was failing intermittently. These network failures resulted in loss of production, loss of throughput, compromised quality, downtime due to reworks, high costs in energy used to rework, and equipment damage or failure. One of the OBJECTIVES of the research was to carry out a performance evaluation of the PROFIBUS network in terms of the possible electromagnetic interference (EMI) within the plant’s PLC network. This topic emanated from the network service providers that kept insisting that the network was unstable, due to possible electromagnetic interference caused by possible high voltage cables running next to the plant network cables. This assumption was without fact, and hence the research was conducted. The QUANTITATIVE research method was used to conduct the research, where simulation of the plant network, using external parameters, were used to carry out the research. Furthermore, experiments were conducted and the physical measurements were performed on the network, where parameters derived from these measurements were used to compare the two networks. In essence, the network was tested under known configurations. The manner in which the network was simulated was that of stepping up the electrical current from the external device, and recording the response of the network. A stand-alone network rig was built and used to carry out the tests, and the results were compared with those obtained from the plant network. / Electrical and Mining Engineering / M. Tech. (Electrical Engineering)

In recent years, middleware for mobile social network has attracted the attention of academia, causing the design and development of various approaches by researchers. This type of middleware facilitates and makes more efficient the development process of mobile social networking applications. Furthermore, middleware solutions also abstract the communication process with others applications, allowing the acquisition, persistence and reuse of social context information and location of users, besides providing API so that developers can access this information quickly and build new social applications. With a view to supporting this new trend of research, this thesis proposes a middleware for mobile social networking, called My-Direct, which makes use of Wi-Fi Direct technology together with the Bluetooth, aiming to provide flexible communication between the nodes of the mobile social network. Along with My-Direct also was be created a mechanism for user privacy based on information available on mobile device, so that the execution of social activities occurs just between partners with some degree of affinity. / Nos últimos anos, o tema middleware para redes sociais móveis têm atraído a atenção do meio acadêmico, causando o projeto e desenvolvimento de diversas soluções por parte dos pesquisadores. Esse tipo de middleware facilita e torna mais eficiente o pro­cesso de desenvolvimento de aplicações de redes sociais para o ambiente móvel. Além disso, essas soluções de middleware também abstraem o processo de comunicação entre parceiros e permitem a aquisição, persistência e reuso de informações de contexto social e de localização do usuário, além de disponibilizarem API para que os desenvolvedores possam acessar essas informações rapidamente e construir novas aplicações sociais Tendo em vista colaborar para esta nova tendência de pesquisa, esta dissertação propõe uma arquitetura de middleware para redes sociais móveis chamada de My-Direct que faz uso da tecnologia Wi-Fi Direct em conjunto com o Bluetooth, visando proporci­onar comunicação flexível entre os nós da rede social móvel. Junto ao My-Direct, tam­bém foi criado um mecanismo de privacidade para o usuário baseado em informações disponíveis no dispositivo móvel, de forma que a execução de atividades sociais ocorra apenas entre parceiros com algum grau de afinidade.

Orientadores: Mauricio Ferreira Magalhães, Fabio Luciano Verdi / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e Computação / Made available in DSpace on 2018-08-09T14:41:11Z (GMT). No. of bitstreams: 1 Wong_Walter_M.pdf: 1265045 bytes, checksum: 15a2435e5676b973ffe726e4757323e4 (MD5) Previous issue date: 2007 / Resumo: A concepção original da arquitetura da Internet foi baseada em uma rede fixa e confiável. Hoje em dia, a Internet se tornou dinâmica e vulnerável aos ataques de segurança. Também não era prevista a necessidade de integração de tecnologias heterogêneas nem de ambientes sem fio. A arquitetura atual apresenta uma série de barreiras técnicas para prover estes serviços, sendo uma das maiores a sobrecarga semântica do Internet Protocol (IP). O endereço IP atua como localizador na camada de rede e como identificador na camada de transporte, impossibilitando novas funcionalidades como a mobilidade e abrindo brechas de segurança. Este trabalho apresenta uma proposta de implementação de uma arquitetura para Internet de nova geração para o provisionamento de novos serviços de forma natural e integrada para a Internet atual. A proposta de arquitetura de implementação oferece suporte à mobilidade, ao multihoming, à segurança, à integração de redes heterogêneas e às aplicações legadas através da introdução de uma nova camada de identificação na arquitetura atual. Esta nova camada tem por objetivo separar a identidade da localização e se tornar uma opção de comunicação para as redes heterogêneas. Mecanismos adicionais foram propostos para prover o suporte às funcionalidades da arquitetura, tais como a resolução de nomes em identificadores, o roteamento baseado no identificador, a gerência de localização e um plano de controle para a troca de mensagens de sinalização fim-a-fim entre os componentes da arquitetura. Para a validação da arquitetura proposta, um protótipo foi implementado e vários testes de desempenho foram realizados para avaliação do overhead da implementação, do modelo de segurança, da robustez e do suporte à mobilidade e às aplicações legadas / Abstract: The original concept of the Internet architecture was based on static and reliable networks. Nowadays, the Internet became more dynamic and vulnerable to security attacks. The integration of heterogeneous technologies and wireless environment were not predicted. The current architecture presents some technical barriers to provide these services. One of these problems is the semantic overload of the Internet Protocol (IP). The IP address acts as locator in the network layer and identifier in the transport layer, preventing new features such as mobility and allowing security flaws. This work presents an implementation proposal of a next generation Internet architecture to provide new services naturally integrated to the Internet. The implementation proposal supports mobility, multihoming, security, heterogeneous networks integration and legacy applications by the introduction of a new identification layer in the current architecture. This new layer will separate the identity from the location and become an option for communication between heterogeneous networks. Additional mechanisms were proposed to support the new functionalities of the architecture, e.g., resolution of names to identifiers, identifier-based routing, location management and a control plane to exchange end-toend signalling control messages between the components of the architecture. In order to evaluate the proposed architecture, a prototype was implemented and some tests were performed considering implementation overhead, security model, robustness and support for mobility and legacy applications / Mestrado / Engenharia de Computação / Mestre em Engenharia Elétrica

Indiana University-Purdue University Indianapolis (IUPUI) / In today's internet world with such a high traffic, it becomes inevitable to have multiple servers representing a single logical server to share enormous load. A very common network configuration consists of multiple servers behind a load balancer. The load balancer determines which server would service a clients request or incoming load from the client. Such a hardware is expensive, runs a fixed policy or algorithm and is a single point of failure. In this paper, we will implement and analyze an alternative load balancing architecture using OpenFlow. This architecture acquires flexibility in policy, costs less and has the potential to be more robust. This paper also discusses potential usage of OpenFlow based load balancing for media gateway selection in SIP-PSTN networks to improve VoIP performance.

Indiana University-Purdue University Indianapolis (IUPUI) / Mobile IP though allows mobility features to a node it suffers from signaling Latencies which are mainly incurred due to the fact that the MN itself is involved in the handover process. To overcome this problem proxy mobile IPv6(PMIPv6) was defined where the mobility signaling is taken care of by a proxy server while keeping track of the MN's movement. PMIPv6 has considerably reduced the handover latency but the demand for real time applications over the network has increased tremendously due to recent explosion of the cloud era. My thesis focuses on increasing the L3 handoff signaling efficiency by reducing the latency. This is achieved by our idea to do both the AAA authentication as well as the LMA registration in PMIPv6 at the same time. The simulation results show that our proposed approach perform better than the current PMIPv6 L3 handover signaling reducing the latency as well as packet loss.