A software product line is a set of software-intensive systems that share a common, managed set of features satisfying the specific needs of a particular market segment or demand. Software product lines capitalize commonality and manage variation to reduce the time, effort, cost and complexity when creating and maintaining products in a product line. Therefore reusing core assets, software product line can address problems such as cost, time-to-market, quality, complexity of developing and maintaining variants, and need to quickly respond to market’s demands. The development of a software product line is different from conventional software development and in the area of education and research of product line there is a lack of a suitable purposefully designed and developed software product line (SPL) that can be used for educational or research purposes. In this thesis we have developed a software product line for turn-based two players distributed board games environment that can be used for educational and research purposes. The software product line supports dynamic runtime update, including games, chat, and security features, via OSGi framework. Furthermore, it supports remote gameplay via local area network and dynamic runtime activity recovery. We delivered a product configuration tool that is used to derive and configure products from the core assets based on feature selection. We have also modeled the software product line’s features and documented its requirements, architecture and user guides. Furthermore, we performed functional and integration tests of the software product line to ensure that the requirements are met according to the requirements specification prescribed by the stakeholders.

Provisioning for power failure is an important element of data center design. It is important to assess both tangible and intangible costs of unplanned data center downtime. These costs must be compared with the capital cost of providing various levels of backup power infrastructure to compute and cooling equipment. Various levels of backup power infrastructure each lead to a most probable transient scenario after utility power failure. Because of differences between facilities, the level of risk that unacceptable compute equipment inlet temperature associated with each level of backup power infrastructure is not standardized; in particular, facilities with differing compute equipment power densities may require different levels of backup power infrastructure to maintain safe operation. Choosing one level of backup power infrastructure above another is not necessarily obvious for every facility, as there may be large gaps in costs and unknown levels of risk for lower levels of provisioning. A first order model is also used to compare inclusion of various thermal capacitance values with experimental results. Room level experiments also illustrate the relative level of risk associated with various levels of provisioning for the same control volume and compute equipment. Although provisioning to back up as much equipment as possible remains the "safest" solution, cost will continue to play a factor in facility design decisions. This work offers a step toward appropriate modeling of data center power failure events and suggests further steps to continue the process.

Universiẗat, Diss.--Heidelberg, 1996.

Today’s massive usage of smartphones has put a high demand on all application developers in the matter of security. For us to be able to keep using all existing and new applications, a process that removes significant security vulnerabilities is essential. To remove these vulnerabilities, the applications have to be tested. In this thesis, we identify six methods for functional and security testing of client-server applications running Android and Python Flask. Regarding functional testing, we implement Espresso testing and RESTful API testing. In regards to the security testing of the system, we do not only implement fuzz testing, sniffing, reverse engineering and SQL injection testing on a system developed by a student group in a parallel project, but also discover a significant security vulnerability that directly affects the integrity and reliability of this system. Out of the six identified testing techniques, reverse engineering exposed the vulnerability. In conjunction with this, we verified that the system’s functionality works as it is supposed to.

Este trabalho descreve a avaliação do Processo Unificado Rational (RUP) realizada com base no Modelo de Maturidade da Capacitação (CMM ou SW-CMM), e a utilização de um sistema de gerência de workflow comercial, Exchange 2000 Server, na implementação de um protótipo de um ambiente de apoio a este processo, chamado de Ambiente de Gerenciamento de Projetos (AGP). O Processo Unificado Rational (RUP) foi avaliado com relação às práticas-chave descritas pelo Modelo de Maturidade da Capacitação (CMM) do Software Engineering Institute (SEI), da Carnegie Mellon University. A avaliação identificou o suporte fornecido por este modelo de processo às organizações que desejam alcançar níveis 2 e 3 do CMM. A avaliação resultou na elaboração de propostas para complementar as macro-atividades (Core Workflows) do RUP, visando satisfazer as práticas-chave do CMM. O CMM apresenta um modelo de avaliação de processo que busca atingir a maturidade dos processos da organização, é específico para o desenvolvimento de software, os aspectos de melhoria contínua são fortemente evidenciados e várias organizações já estão utilizando-o com sucesso. O RUP surgiu como uma proposta de unificar as melhores práticas de desenvolvimento de software. Foi experimentada a utilização de um sistema de gerência de workflow, de fato um servidor de colaboração, para apoiar o processo de desenvolvimento de software. A ferramenta desenvolvida foi avaliada com base em requisitos considerados, por alguns autores da área, desejáveis em um ambiente de apoio ao processo de desenvolvimento. O protótipo do ambiente de gerenciamento de projetos é uma ferramenta de suporte baseada na Web, que visa auxiliar os gerentes de projeto de software nas atividades de gerenciamento e controle, e ajudar na interação e troca de informações entre os membros da equipe de desenvolvimento. O Processo Unificado apresenta uma abordagem bem-definida dos processos de engenharia de software e de gerenciamento de projetos de software, mas não se concentra em atividades de gerenciamento de sistemas. Ele apresenta lacunas em atividades envolvendo gerenciamento de recursos humanos, gerenciamento de custos e gerenciamento de aquisição. AGP é uma ferramenta flexível que pode ser acessada pela Internet, suporta a colaboração entre os membros de uma equipe, e oferece os benefícios da Web, como navegação intuitiva através de links e páginas. Esta ferramenta ajuda no suporte ao gerenciamento, fornecendo opções para planejar e monitorar o projeto, e suporta eventos, como mudança de estados, e comunicação aos usuários de suas novas tarefas. / This master dissertation describes the assessment of the Rational Unified Process (RUP) based on the Capability Maturity Model for Software (SW-CMM or CMM), and the implementation of a prototype tool to support this process based on of-the-shelf Workflow Management System, Exchange 2000 Server. The prototype developed is called Project Management Environment (PME). Rational Unified Process (RUP) was assessed based on the key practices described for the Capability Maturity Model (CMM) at the Carnegie Mellon Software Engineering Institute. The assessment identified the facilities that RUP offers to support an organization aiming at CMM levels 2 and 3. The assessment resulted in the elaboration of propositions to complement the Rational Unified Process in order to satisfy the key process areas of CMM. CMM shows a process model that is far fetched to reach the process maturity of an organization, is specific for the software development, and strongly emphasizes the aspects of continuous improvement and several organizations already used it with success. RUP describes how to apply best practices of software engineering. It was experimented the use of a Workflow Management System, in fact a collaboration server, to support the software development process. The experimental environment was assessed considering the requirements identified by various researchers for an environment to effectively support a software development process. The prototype software development environment is a web-based process support system, which provides means to assist the management of software development projects and help the interaction and exchange of information between disperse members of a development. The Rational Unified Process presents a well defined approach on software project management and software engineering processes, but it is not an approach centered on systems management concerns. Therefore it lacks activities involving issues as cost management, human resource management, communications management, and procurement management. PME is a flexible tool that can be accessed through the Internet, supporting the collaboration between team members, and offering the benefits of the Web, with intuitive navigation through of links and pages. It helps to support management control, providing options to plan and monitor the project, and supports events of the process, as changing states, and communicates users of their attributed tasks.

This study analyses the nature and implementation of electronic commerce in order to identify possible problems for taxation and pinpoint those problems which may be relevant to South Africa. Solutions suggested by certain countries and institutions are evaluated for possible implementation in South Africa. The study suggests that although current taxation legislation in South Africa is apP'icable to electronic commerce transactions it is not sufficient to cater effectively for this type of business. The conclusion reached Is that international co-operation is essential in finding solutions. A number of recommendations are made regarding aspects of South African taxation legislation which need to be clarified through policy decisions. Title of / Taxation / M.Comm.

Several technologies and languages exist for the development and implementation of distributed systems. Furthermore, several models for teaching computer programming and teaching programming in a distance-based educational environment exist. Limited literature, however, is available on models for teaching distributed computing in a distance-based educational environment. The focus of this study is to examine how distributed computing should be taught in a distance-based educational environment so as to ensure effective and quality learning for students. The required effectiveness and quality should be comparable to those for students exposed to laboratories, as commonly found in residential universities. This leads to an investigation of the factors that contribute to the success of teaching distributed computing and how these factors can be integrated into a distance-based teaching model. The study consisted of a literature study, followed by a comparative study of available tools to aid in the learning and teaching of distributed computing in a distance-based educational environment. A model to accomplish this teaching and learning is then proposed and implemented. The findings of the study highlight the requirements and challenges that a student of distributed computing in a distance-based educational environment faces and emphasises how the proposed model can address these challenges. This study employed qualitative research, as opposed to quantitative research, as qualitative research methods are designed to help researchers to understand people and the social and cultural contexts within which they live. The research methods employed are design research, since an artefact is created, and a case study, since “how” and “why” questions need to be answered. Data collection was done through a survey. Each method was evaluated via its own well-established evaluation methods, since evaluation is a crucial component of the research process. / Computing / M. Sc. (Computer Science)

This work reports on virtualization and cloud computing technologies. It evaluates their strengths and weaknesses as well as describes the examples of its deployment. The document serves as a concise and comprehensive guide, describing the necessary theory along with the practical use. It is all demonstrated on a real project. The practical part refers to the data environment of the Fire Rescue Service of South Bohemia Region and represents the usage of studied technologies. The analysis also includes project´s financial and technical aspects.

Este trabalho descreve a avaliação do Processo Unificado Rational (RUP) realizada com base no Modelo de Maturidade da Capacitação (CMM ou SW-CMM), e a utilização de um sistema de gerência de workflow comercial, Exchange 2000 Server, na implementação de um protótipo de um ambiente de apoio a este processo, chamado de Ambiente de Gerenciamento de Projetos (AGP). O Processo Unificado Rational (RUP) foi avaliado com relação às práticas-chave descritas pelo Modelo de Maturidade da Capacitação (CMM) do Software Engineering Institute (SEI), da Carnegie Mellon University. A avaliação identificou o suporte fornecido por este modelo de processo às organizações que desejam alcançar níveis 2 e 3 do CMM. A avaliação resultou na elaboração de propostas para complementar as macro-atividades (Core Workflows) do RUP, visando satisfazer as práticas-chave do CMM. O CMM apresenta um modelo de avaliação de processo que busca atingir a maturidade dos processos da organização, é específico para o desenvolvimento de software, os aspectos de melhoria contínua são fortemente evidenciados e várias organizações já estão utilizando-o com sucesso. O RUP surgiu como uma proposta de unificar as melhores práticas de desenvolvimento de software. Foi experimentada a utilização de um sistema de gerência de workflow, de fato um servidor de colaboração, para apoiar o processo de desenvolvimento de software. A ferramenta desenvolvida foi avaliada com base em requisitos considerados, por alguns autores da área, desejáveis em um ambiente de apoio ao processo de desenvolvimento. O protótipo do ambiente de gerenciamento de projetos é uma ferramenta de suporte baseada na Web, que visa auxiliar os gerentes de projeto de software nas atividades de gerenciamento e controle, e ajudar na interação e troca de informações entre os membros da equipe de desenvolvimento. O Processo Unificado apresenta uma abordagem bem-definida dos processos de engenharia de software e de gerenciamento de projetos de software, mas não se concentra em atividades de gerenciamento de sistemas. Ele apresenta lacunas em atividades envolvendo gerenciamento de recursos humanos, gerenciamento de custos e gerenciamento de aquisição. AGP é uma ferramenta flexível que pode ser acessada pela Internet, suporta a colaboração entre os membros de uma equipe, e oferece os benefícios da Web, como navegação intuitiva através de links e páginas. Esta ferramenta ajuda no suporte ao gerenciamento, fornecendo opções para planejar e monitorar o projeto, e suporta eventos, como mudança de estados, e comunicação aos usuários de suas novas tarefas. / This master dissertation describes the assessment of the Rational Unified Process (RUP) based on the Capability Maturity Model for Software (SW-CMM or CMM), and the implementation of a prototype tool to support this process based on of-the-shelf Workflow Management System, Exchange 2000 Server. The prototype developed is called Project Management Environment (PME). Rational Unified Process (RUP) was assessed based on the key practices described for the Capability Maturity Model (CMM) at the Carnegie Mellon Software Engineering Institute. The assessment identified the facilities that RUP offers to support an organization aiming at CMM levels 2 and 3. The assessment resulted in the elaboration of propositions to complement the Rational Unified Process in order to satisfy the key process areas of CMM. CMM shows a process model that is far fetched to reach the process maturity of an organization, is specific for the software development, and strongly emphasizes the aspects of continuous improvement and several organizations already used it with success. RUP describes how to apply best practices of software engineering. It was experimented the use of a Workflow Management System, in fact a collaboration server, to support the software development process. The experimental environment was assessed considering the requirements identified by various researchers for an environment to effectively support a software development process. The prototype software development environment is a web-based process support system, which provides means to assist the management of software development projects and help the interaction and exchange of information between disperse members of a development. The Rational Unified Process presents a well defined approach on software project management and software engineering processes, but it is not an approach centered on systems management concerns. Therefore it lacks activities involving issues as cost management, human resource management, communications management, and procurement management. PME is a flexible tool that can be accessed through the Internet, supporting the collaboration between team members, and offering the benefits of the Web, with intuitive navigation through of links and pages. It helps to support management control, providing options to plan and monitor the project, and supports events of the process, as changing states, and communicates users of their attributed tasks.

A virtualização é uma tecnologia chave para a computação em nuvem que permite fornecer recursos computacionais, em forma de máquinas virtuais, para o consumo de serviços de computação. Nos ambientes de computação em nuvem, é importante manter sob controle a alocação de máquinas virtuais nos servidores físicos. Uma alocação adequada implica na redução de custos com hardware, energia e refrigeração, além da melhora da qualidade de serviço. Hipervisores recentes implementam mecanismos para reduzir o consumo de memória RAM através do compartilhamento de páginas idênticas entre máquinas virtuais. Esta dissertação apresenta um novo algoritmo de alocação de máquinas virtuais que busca o equilíbrio no uso dos recursos de CPU, memória, disco e rede e, sobretudo, considera o potencial de compartilhamento de memória entre máquinas virtuais. Através de simulações em cenários distintos, verificou-se que o algoritmo é superior à abordagem padrão na questão do uso equilibrado de recursos e que, considerando o compartilhamento de memória, houve um ganho significativo na disponibilidade deste recurso ao final das alocações. / Virtualization is a key technology for cloud computing, it provides computational resources as virtual machines for consumption of computing services. In cloud computing environments it is important to keep under control the allocation of virtual machines in physical servers. A good allocation brings benefits such as reduction costs in hardware, power, and cooling, also improving the quality of service. Recent hypervisors implement mechanisms to reduce RAM consumption by sharing identical pages between virtual machines. This dissertation presents a new algorithm for virtual machines allocation that seeks the balanced use of CPU, memory, disk, and network. In addition, it considers the potential for sharing memory among virtual machines. Simulations on three distinct scenarios demonstrate that it is superior to the standard approach when considering the balanced use of resources. Considering shared memory, there was an appreciable gain in availability of resources.