Home automation systems (HASs)seek to improve the quality of life for individuals through the automation of household devices. Recently, there has been a trend, in academia and industry, to research and develop low-cost Wireless Sensor Network (WSN) based HASs (Varchola et al. 2007). WSNs are designed to achieve a low-cost wireless networking solution, through the incorporation of limited processing, memory, and power resources. Consequently, providing secure and reliable remote access for resource limited WSNs, such as WSN based HASs, poses a significant challenge (Perrig et al. 2004). This thesis introduces the development of a hybrid communications approach to increase the resistance of WSN based HASs to remote DoS flooding attacks targeted against a third party. The approach is benchmarked against the dominant GHS remote access approach for WSN based HASs (Bergstrom et al. 2001), on a WSN based HAS test-bed, and shown to provide a minimum of a 58.28%, on average 59.85%, and a maximum of 61.45% increase in remote service availability during a DoS attack. Additionally, a virtual home incorporating a cryptographic based DoS detection algorithm, is developed to increase resistance to remote DoS flooding attacks targeted directly at WSN based HASs. The approach is benchmarked against D-WARD (Mirkovic 2003), the most effective DoS defence identified from the research, and shown to provide a minimum 84.70%, an average 91.13% and a maximum 95.6% reduction in packets loss on a WSN based HAS during a DoS flooding attack. Moreover, the approach is extended with the integration of a virtual home, hybrid communication approach, and a distributed denial of defence server to increase resistance to remote DoS attacks targeting the home gateway. The approach is again benchmarked against the D-WARD defence and shown to decrease the connection latency experienced by remote users by a minimum of 90.14%, an average 90.90%, and a maximum 91.88%.

Em um mundo tecnológico e globalmente interconectado, em que indivíduos e organizações executam transações na web com frequência, a questão da segurança de software é imprescindível, ela é necessária em diversos nichos: segurança das redes de computadores, dos computadores e dos softwares. A implantação de um sistema de segurança que abrange todos os aspectos é extensa e complexa, ao mesmo tempo em que a exploração de vulnerabilidades e ataques é exponencialmente crescente. Por causa da natureza do software e de sua disponibilidade na web, a garantia de segurança nunca será total, porém é possível planejar, implementar, medir e avaliar o sistema de segurança e finalmente melhorá-la. Atualmente, o conhecimento específico em segurança é detalhado e fragmentado em seus diversos nichos, a visão entre os especialistas de segurança é sempre muito ligada ao ambiente interno da computação. A medição de atributos de segurança é um meio de conhecer e acompanhar o estado da segurança de um software. Esta pesquisa tem como objetivo apresentar uma abordagem top-down para medição da segurança de acesso de aplicações web. A partir de um conjunto de propriedades de segurança reconhecidas mundialmente, porém propriedades estas intangíveis, é proposta uma metodologia de medição e priorização de atributos de segurança para conhecer o nível de segurança de aplicações web e tomar as ações necessárias para sua melhoria. Define-se um modelo de referência para segurança de acesso e o método processo de análise hierárquica apoia a obtenção de atributos mensuráveis e visualização do estado da segurança de acesso de uma aplicação web. / In a technological world and globally interconnected, in which individuals and organizations perform transactions on the web often, the issue of software security is essential, it is needed in several niches: security of computer networks, computers and software. The implementation of a security system that covers all aspects is extensive and complex, while the exploitation of vulnerabilities and attacks are increasing exponentially. Because of the nature of software and its availability on the web, ensure security will never be complete, but it is possible to plan, implement, measure and evaluate the security system and ultimately improve it. Currently, the specific knowledge in security is detailed and fragmented into its various niches; the view among security experts is always connected to the internal environment of computing. The measurement of security attributes is a way to know and monitor the state of software security. This research aims to present a top-down approach for measuring the access security of web applications. From a set of security properties globally recognized, however these intangible properties, I propose a measurement methodology and prioritization of security attributes to meet the security level of web applications and take necessary actions for improvement. It is defined a reference model for access security and a method of analytic hierarchy process to support the achievement of measurable attributes and status of the access security of a web application.

Em um mundo tecnológico e globalmente interconectado, em que indivíduos e organizações executam transações na web com frequência, a questão da segurança de software é imprescindível, ela é necessária em diversos nichos: segurança das redes de computadores, dos computadores e dos softwares. A implantação de um sistema de segurança que abrange todos os aspectos é extensa e complexa, ao mesmo tempo em que a exploração de vulnerabilidades e ataques é exponencialmente crescente. Por causa da natureza do software e de sua disponibilidade na web, a garantia de segurança nunca será total, porém é possível planejar, implementar, medir e avaliar o sistema de segurança e finalmente melhorá-la. Atualmente, o conhecimento específico em segurança é detalhado e fragmentado em seus diversos nichos, a visão entre os especialistas de segurança é sempre muito ligada ao ambiente interno da computação. A medição de atributos de segurança é um meio de conhecer e acompanhar o estado da segurança de um software. Esta pesquisa tem como objetivo apresentar uma abordagem top-down para medição da segurança de acesso de aplicações web. A partir de um conjunto de propriedades de segurança reconhecidas mundialmente, porém propriedades estas intangíveis, é proposta uma metodologia de medição e priorização de atributos de segurança para conhecer o nível de segurança de aplicações web e tomar as ações necessárias para sua melhoria. Define-se um modelo de referência para segurança de acesso e o método processo de análise hierárquica apoia a obtenção de atributos mensuráveis e visualização do estado da segurança de acesso de uma aplicação web. / In a technological world and globally interconnected, in which individuals and organizations perform transactions on the web often, the issue of software security is essential, it is needed in several niches: security of computer networks, computers and software. The implementation of a security system that covers all aspects is extensive and complex, while the exploitation of vulnerabilities and attacks are increasing exponentially. Because of the nature of software and its availability on the web, ensure security will never be complete, but it is possible to plan, implement, measure and evaluate the security system and ultimately improve it. Currently, the specific knowledge in security is detailed and fragmented into its various niches; the view among security experts is always connected to the internal environment of computing. The measurement of security attributes is a way to know and monitor the state of software security. This research aims to present a top-down approach for measuring the access security of web applications. From a set of security properties globally recognized, however these intangible properties, I propose a measurement methodology and prioritization of security attributes to meet the security level of web applications and take necessary actions for improvement. It is defined a reference model for access security and a method of analytic hierarchy process to support the achievement of measurable attributes and status of the access security of a web application.

This diploma thesis deals with the methods used to ensure access and communication security in large-scale SAP information systems. It deals with the analysis of existing methods, compares them, and identifies how the methods are usable in the operation of large-scale SAP information systems, as well as it identifies methods that fail in this environment. Justification of methods usability is carried out. Attention is focused on the use and implementation of single sign-on safe authentication methods, secure sharing of user identity and secure communication within the framework of a large-scale SAP information system. In this thesis is carried out a design proposal of the architecture in order to ensure access and communication security in SAP information systems using the LDAP service, SNC Kerberos and single sign-on authentication. In the practical example is documented the detailed technical implementation of this architecture. Furthermore, this thesis deals with the specifics which exist especially in large-scale SAP information systems in the area of access and communication security and documents the appropriate ways to address them.

M. Tech. Business Information Systems / Although owners of Internet cafés extend the freedom to have Internet access to the community, they fail to tighten their computer security to safeguard the private information of their customers. This dissertation provides a conceptual framework for improving information security in the Internet Café, to help and ensure data privacy, data integrity, risk management and information security (IS) behaviour. The study investigated the information security issues that are faced by users of Internet cafés and explored the effects of these issues. The framework shows how users can improve their physical security to reach higher standards of information privacy over the Internet.

Auf der Grundlage der Analyse der infrastrukturellen Bedingungen im Lehr- und Forschungsbergwerk der TU Bergakademie Freiberg wurden Möglichkeiten zur Weiterentwicklung des Bergwerkes untersucht. Der vorgestellte Ansatz zur Lösung der logistischen Probleme und damit verbundener Möglichkeiten zur effizienten Nutzung des Bergwerkes für Lehre und Forschung durch den Bau einer Rampe verkörpert die Basis weiterer Untersuchungen. Die Vielfalt der Probleme, die sich aus der Implementierung einer neuen Struktur in das bestehende historische Bergwerk ergeben, wurde erörtert. Gleichzeitig wurde ausführlich auf die sich ergebenden Probleme zur Gewährleistung der Personensicherheit und der Sicherheit technischer Einrichtungen, veränderter Bedingungen der Zutrittskontrolle zum Grubenbetrieb und der komplexen Struktur der Informationsverwaltung hingewiesen. Abschließend wurde die neue administrative Struktur des Bergwerkes unter wirtschaftlichen Aspekten dargestellt.

Auf der Grundlage der Analyse der infrastrukturellen Bedingungen im Lehr- und Forschungsbergwerk der TU Bergakademie Freiberg wurden Möglichkeiten zur Weiterentwicklung des Bergwerkes untersucht. Der vorgestellte Ansatz zur Lösung der logistischen Probleme und damit verbundener Möglichkeiten zur effizienten Nutzung des Bergwerkes für Lehre und Forschung durch den Bau einer Rampe verkörpert die Basis weiterer Untersuchungen. Die Vielfalt der Probleme, die sich aus der Implementierung einer neuen Struktur in das bestehende historische Bergwerk ergeben, wurde erörtert. Gleichzeitig wurde ausführlich auf die sich ergebenden Probleme zur Gewährleistung der Personensicherheit und der Sicherheit technischer Einrichtungen, veränderter Bedingungen der Zutrittskontrolle zum Grubenbetrieb und der komplexen Struktur der Informationsverwaltung hingewiesen. Abschließend wurde die neue administrative Struktur des Bergwerkes unter wirtschaftlichen Aspekten dargestellt.