Orientador: Lee Luan Ling / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-04T02:56:17Z (GMT). No. of bitstreams: 1 Pereira_TatianaBrito_M.pdf: 2502862 bytes, checksum: 4f913e9451b6cbf542c6f1335b1619d8 (MD5) Previous issue date: 2004 / Resumo: O crescimento explosivo e a natureza heterogênea da Internet demandam ferramentas ¿inteligentes¿ que permitam aos protocolos de roteamento adaptarem-se à situação corrente da rede (topologia e situação de congestionamento). Ferramentas inteligentes, porém, significam, na maioria das vezes, grande sobrecarga de processamento e comunicação. O presente trabalho apresenta, além de uma nova estratégia de roteamento OSPF adaptativo baseado em estimação de banda, uma plataforma de simulação capaz de expor o desempenho de uma rede de interconexão submetida (ou não) a esta nova estratégia. A avaliação de desempenho é realizada graças a um modelo, desenvolvido no simulador OPNET, que adiciona ao modelo de um roteador os módulos para estimação de banda e atualização de custos. Os módulos (de estimação de banda e de atualização de custo) adicionados permitem que o protocolo OSPF tome suas decisões de roteamento baseando-se nas condições de congestionamento da rede e nos índices de qualidade desejados para os enlaces. Neste ambiente de simulação, a topologia da rede é representada por um grafo e o tráfego, a que estará sujeita a rede, durante o período de simulação, é especificado por funções de distribuição que atuam durante um intervalo determinado em um roteador específico da rede. A possibilidade de se estabelecer diversas funções de geração de tráfego, atuando a partir de diversos pontos da rede em intervalos independentes, garante certa representação do dinamismo do tráfego encontrado nas redes atuais. Como resultado das simulações, temos uma análise do impacto desta estratégia adaptativa em parâmetros de desempenho de rede, em comparação com o impacto do roteamento OSPF tradicional / Abstract: Internet increase and diversity demand ¿smart¿ tools that could make possible to routing protocols self-adapt to network current state (its topology and congestion situation). Smart tools, although, can result in great processing and communication overload. This work presents, besides a new adaptive OSPF routing strategy based on bandwidth estimations, a simulation platform able to expose results of network performance while experimenting (or not) the proposed adaptive routing strategy. The performance analysis is accomplished due to a model, developed in OPNET network simulator, that adds to a router model modules to bandwidth estimation and link cost updating. These additional modules allow OSPF protocol to take its routing decisions based on network link conditions and on desired link qualities. Network topology is represented by a graph and the traffic presented during simulation is specified by distribution functions acting in specific routers during established intervals. The possibility of configuring various traffic generation functions, acting from various network points in independent intervals, ensures certain network traffic dynamic representation. The simulation results offer an analysis of the proposed OSPF adaptive routing strategy, in comparison to the conventional OSPF routing, in terms of network performance parameters / Mestrado / Telecomunicações e Telemática / Mestre em Engenharia Elétrica

With the rapid adoption of multimedia network technologies, a number of companies and standards bodies are introducing technologies that enhance user experience in networked multimedia environments. These technologies focus on device discovery, connection management, control, and monitoring. This study focused on control and monitoring. Multimedia networks make it possible for devices that are part of the same network to reside in different physical locations. These devices contain parameters that are used to control particular features, such as speaker volume, bass, amplifier gain, and video resolution. It is often necessary for changes in one parameter to affect other parameters, such as a synchronised change between volume and bass parameters, or collective control of multiple parameters. Thus, relationships are required between the parameters. In addition, some devices contain parameters, such as voltage, temperature, and audio level, that require constant monitoring to enable corrective action when thresholds are exceeded. Therefore, a mechanism for monitoring networked devices is required. This thesis proposes relationships that are essential for the proper functioning of a multimedia network and that should, therefore, be incorporated in standard form into a protocol, such that all devices can depend on them. Implementation mechanisms for these relationships were created. Parameter grouping and monitoring capabilities within mixing console implementations and existing control protocols were reviewed. A number of requirements for parameter grouping and monitoring were derived from this review. These requirements include a formal classification of relationship types, the ability to create relationships between parameters with different underlying value units, the ability to create relationships between parameters residing on different devices on a network, and the use of an event-driven mechanism for parameter monitoring. These requirements were the criteria used to govern the implementation mechanisms that were created as part of this study. Parameter grouping and monitoring mechanisms were implemented for the XFN protocol. The mechanisms implemented fulfil the requirements derived from the review of capabilities of mixing consoles and existing control protocols. The formal classification of relationship types was implemented within XFN parameters using lists that keep track of the relationships between each XFN parameter and other XFN parameters that reside on the same device or on other devices on the network. A common value unit, known as the global unit, was defined for use as the value format within value update messages between XFN parameters that have relationships. Mapping tables were used to translate the global unit values to application-specific (universal) units, such as decibels (dB). A mechanism for bulk parameter retrieval within the XFN protocol was augmented to produce an event-driven mechanism for parameter monitoring. These implementation mechanisms were applied to an XFN-protocol-compliant graphical control application to demonstrate their usage within an end user context. At the time of this study, the XFN protocol was undergoing standardisation within the Audio Engineering Society. The AES-64 standard has now been approved. Most of the implementation mechanisms resulting from this study have been incorporated into this standard.

Rural Internet connectivity projects aimed at bridging the digital divide have mushroomed across many developing countries. Most of the projects are deployed as community centred projects. In most of the cases the initial deployment of these projects is funded by governments, multilateral institutions and non-governmental organizations. After the initial deployment, financial sustainability remains one of the greatest challenges facing these projects. In the light of this, externally funded ICT4D interventions should just be used for “bootstrapping” purposes. The communities should be “groomed” to take care of and sustain these projects, eliminating as soon as possible a dependency on external funding. This master thesis presents the design and the implementation of a generic architecture for the management of the costs associated with running a computer network connected to the Internet, The proposed system, called the Network Revenue Management System, enables a network to generate revenue, by charging users for the utilization of network resources. The novelty of the system resides in its flexibility and adaptability, which allow the exploration of both conventional and non-conventional billing options, via the use of suitable ‘adapters’. The final goal of the exploration made possible by this system is the establishment of what is regarded as equitable charging in rural, marginalized communities - such as the community in Dwesa, South Africa.

The basis of this thesis is a discussion of the pros and cons of incorporating the Internet as an educational tool for exploring career pathways.

The purpose of this study was to describe the attitudes of a group of nurses towards the use of computers in a Southern California Veterans Affairs hospital.

This study looks at the impact of E-commerce on direct selling companies, and examines how the direct selling companies react to the effects of E-commerce business.

This study looks at the impact of E-commerce on direct selling companies, and examines how the direct selling companies react to the effects of E-commerce business.

South African home users of the Internet use the Internet to perform various everyday functions. These functions include, but are not limited to, online shopping, online gaming, social networking and online banking. Home users of online banking face multiple threats, such as phishing and social engineering. These threats come from hackers attempting to obtain confidential information, such as online banking authentication credentials, from home users. It is, thus, essential that home users of online banking be made aware of these threats, how to identify them and what countermeasures to implement to protect themselves from hackers. In this respect, information security awareness (ISA) programmes are an effective way of making the home users of online banking aware of both the threats they face and the countermeasures available to protect themselves from these threats. There are certain legal requirements with which South African banks have to comply when implementing ISA initiatives. Non-compliance or failure to demonstrate due care and due diligence should a security incident occur will result in financial penalties for the bank as well as possible brand damage and loss of customers. Banks implement international best practice recommendations in an effort to comply with legislation. These include recommendations for information security awareness. This research investigated both information security best practice recommendations and information security legal requirements for information security awareness. A selected list of information security best practices was investigated for best practice recommendations while a selected list of information security legislation was investigated for legal requirements imposed on South African banks. A gap analysis was performed on both these recommendations and requirements to determine whether the implementation of best practice recommendations resulted in compliance with legal requirements. The gap analysis found that the implementation of best practice recommendations does not result in compliance with legal requirements. Accordingly, the outcome of this research highlighted the importance of understanding the legal requirements and ensuring that adequate controls are in place with which to achieve compliance. / Business Information systems / Msc. (Information systems)

No description available.

Thesis ( M. Tech. (School of Information Technology )) - Central University of Technology, Free State, 2014 / The aim of this study has been to find out how the community in the remote areas of South Africa access government information. The study is based on four villages, two in the Northern Cape Province (Heuningvlei and Galeshewe) and two in Limpopo Province (The Oaks and Finala). A quantitative design was used. Open and closed-ended questionnaires were used to collect data from the community. Out of 200 questionnaires distributed only 144 responses were received. Responses in the questionnaires were tabulated, coded and processed using the Statistical Package for Social Sciences (SPSS) programme. Based on the analysis in Table 4.13, the study showed that 44 percent of the sampled community have access to information through Television which they classified as technology. Shortage of telecentres, distance to telecentres, age, lack of education, monthly income, infrastructure and transport cost were some of the important factors contributing to a lack of access to information. Some of the findings are that most of the telecentres are located far from towns, more than 7 kilometres from the village. Ideally, telecentres should be located near the community, within a short walking distance. It is recommended that provision/establishment for easy access to information and communication services by the Universal Service and Access Agency of South Africa (USAASA) in the remote areas in the Northern Cape and Limpopo province is strongly considered for implementation. This will overcome the gap that exists between the urban and semi-urban communities regarding access to human rights information such as rights to life, equality, freedom of speech, assembly and access to information. It is also assumed that the implementation of telecentres and Internet Cafes, in order to facilitate the adoption of e-government information by people residing in remote areas (semi-urban areas) such as Heuningvlei, Galeshewe, The Oaks and Finala will contribute to better access to human rights. The study also recommends that the service costs charged by the telecentre and Internet Cafes should not be expensive. This will assist the community to afford to pay Internet services. Information is important for decision-making. For this reason, it is recommended that continued campaigns on awareness about the mportance of access to information through telecentres and Internet Cafes should be conducted.