Diese Arbeit betrachtet zwei anspruchsvolle Probleme aus dem Bereich Computer- und Kommunikationssicherheit und Vertrauen. Beim Datenbank-Serviceprovider-Problem moechte ein Anwender seine Datenbank an einen Datenbank-Serviceprovider (DSP) uebergeben, damit dieser sie betreiben und ihm zur Verfuegung stellen kann. Er vertraut diesem DSP, und damit auch vertraglichen Abmachungen, nur bedingt und muss die Vertraulichkeit seiner Daten durch technische Massnahmen sicherstellen. Das zweite Problem ist das Verbreiten verlaesslicher Reputationsinformation ueber eine (moeglicherweise sehr grosse) Anzahl von Netzwerk-Knoten in einer Peer-to-Peer-Umgebung (P2P). Beide Probleme straeuben sich hartnaeckig gegen einfache Loesungen. Im Gegensatz zu traditionellen Sicherheitsproblemen in der Informatik hat der Gegner in beiden ein hohes Mass an Kontrolle ueber die Situation. Der nicht ausreichend vertrauenswuerdige DSP muss in der Lage sein, die Daten seines Kunden zu verarbeiten, ohne etwas ueber sie zu lernen, was intuitiv wie ein Widerspruch erscheint. In P2P-Anwendungen ist es wuenschenswert, dass Knoten anonym beitreten und jederzeit wieder austreten koennen, aber diese Anonymitaet erleichtert es, falsche Reputationsinformation zu verbreiten. Ein Knoten, der erstmalig in ein P2P-Netzwerk eintritt, muss den behaupteten Beobachtungen anderer Knoten vertrauen. Die Resultate dieser Arbeit sind keine Idealloesungen, und dennoch aufschlussreich in mehrerlei Hinsicht: Es werden gelockerte, aber immer noch nuetzliche Sicherheitsbegriffe fuer das DSP-Problem vorgeschlagen; es werden theoretische Grenzen des DSP-Loesungsraums gezogen; und die Auswirkung feindseligen Verhaltens in P2P-Reputationssystemen wird durch heuristische Methoden reduziert. Ein Nebeneffekt unserer Arbeit ist ein speziell fuer Reputationssysteme in P2P-Netzwerken geeignetes Simulations-Tool, das zum Vergleich und zum Fine-Tuning bestehender und zukuenftiger Forschungsarbeiten genutzt werden kann. / In this thesis we discuss two demanding problems from the field of computer and communication security that involve trust. The first is known as the database service provider problem: A database owner wants a database service provider (DSP) to host her database. She only trusts this DSP to a limited extent, so she does not want to rely solely on contractual solutions. It is therefore necessary to enforce confidentiality of her data by technical means. The second problem concerns a (potentially very large) number of network nodes in a peer-to-peer (P2P) environment. Both problems are notoriously hard because, other than in traditional computer security problems, the adversary has a lot of control over the situation. The untrusted DSP needs to be able to process the data without learning anything about it, which seems to be a contradiction. In P2P applications it is desirable that nodes can join anonymously, but anonymity makes it easy to spread false reputation information. A node that enters a P2P application network for the first time needs to trust the claimed observations of other nodes, independent of the rate of malicious behaviour. Our findings are not perfect solutions, but nevertheless instructive in several ways: We propose relaxed, but still practically useful, notions of security for the DSP problem; we identify theoretical limitations of the DSP solution space; and we gradually reduce the impact of adversarial behaviour in P2P reputation systems using heuristic methods. As a side effect of our work, we present a special-purpose framework for simulation of P2P reputation systems that can be used to compare and fine-tune previous and upcoming work.

Die vorliegende Dissertation präsentiert eine umfassende Analyse und Strukturierung des Marktes für netzbasierte Dienste. Basierend auf einer detaillierten Untersuchung des ASP-Angebotes und der ASP-Nachfrage in Europa werden geeignete Institutionen und Informationssubstitute für die Anpassung (Matching) des ASP-Angebotes und der ASP-Nachfrage identifiziert und getestet. Die Strukturierung der Angebotsseite umfasst neben der Bewertung der Marktlage die Entwicklung der ASP-Wertschöpfungskette, die Einordnung in die Systematik der digitalen Güter, die Beschreibung der ASP-Technologien und -Geschäftsmodelle und den Vergleich des ASP-Geschäftsmodells mit der klassischen Softwarenutzung und dem Konzept der virtuellen Organisationen. Die Ergebnisse der Untersuchungen zeigen vorhandene Defizite in der Informations- und Kommunikationspolitik der ASP-Angebotsseite auf. Für die Strukturierung der Nachfrageseite für netzbasierte Dienste werden die Theorien der Auslagerung (Outsourcing) von Informationstechnologien, die Methoden und Instrumente der Kosten- und Nutzenmessung und die Theorie der Transaktionsphasen der Auslagerung angewendet. Kern der wissenschaftlichen Untersuchung bildet die empirische Untersuchung des ASP-Nachfragemarktes in Deutschland und anderen europäischen Ländern. Die Erkenntnisse der Analyse des ASP-Angebotes und der ASP-Nachfrage werden gegenübergestellt und Methoden zur Abstimmung von ASP-Angebot und Nachfrage mit Hilfe der Transaktionskostentheorie und den Theorien der Informations- und Institutionenökonomie abgeleitet. Barrieren, Intransparenzen und Informationsasymmetrien werden auf beiden Seiten aufgezeigt und darauf aufbauend Informationssubstitute für netzbasierte Dienste identifiziert. Erfahrungs- und Vertrauenseigenschaften werden mit Hilfe von Informationssubstituten in einem Onlinebefragungsexperiment hinsichtlich der Wahrnehmung, Wirkung und möglicher Zahlungsbereitschaften überprüft. Aus den Ergebnissen des Onlinebefragungsexperimentes werden Anforderungen an die Informations- und Kommunikationspolitik und Strategien zur Reduzierung der Informationsasymmetrie für netzbasierte Dienste entwickelt. Das Ergebnis der Arbeit ist die Ableitung relevanter Kriterien für die Darstellung und Bewertung der Leistungsbündel netzbasierter Dienste und die Entwicklung von Strategien zur Reduzierung der Transaktionsunsicherheit durch die Identifizierung und Integration von Informationssubstituten für netzbasierte Dienste. / This dissertation presents a comprehensive analysis and conceptual framework of the web-based Application Service Provider (ASP) market. Based on a detailed analysis of ASP supply and demand in Europe, appropriate institutions and information substitutes for the matching process on the ASP market are identified and evaluated. The conceptual framework for the supply side is developed by evaluating the market situation, designing an ASP value chain, classifying digital goods, describing the ASP technologies and business models. These are then compared with the classic model of software utilization and the concept of virtual organizations. The results indicate present deficits in the supply-side information and communication policy. For ASP demand, theories of outsourcing of information technologies, methods and instruments of cost-and-utility-measuring and the theory of transaction phases of outsourcing are used. The basis for both supply-side and demand-side evaluations is an empirical analysis of the European ASP market. We compare the outcome of the supply and demand analyses and derive methods for their coordination by the transaction cost theory and the theories of information and institution economy. Barriers, lack of transparencies and information asymmetries are identified on both sides and thus, information substitutes for web-based services are developed. Information substitutes for experience and trust characteristics are evaluated with an online-questionnaire completed by key participants based on their perception, action and willingness to pay. From those results, we deduce strategies for reducing the information asymmetry. The result of the work is the deduction of relevant criteria for the presentation and evaluation for the supply of web-based services and the development of strategies for reducing the transaction uncertainty by identifying and integrating information substitutes.

Am 29. und 30. November 2012 fand am Hasso-Plattner-Institut für Softwaresystemtechnik GmbH in Potsdam der 5. Deutsche IPv6 Gipfel 2012 statt, als dessen Dokumentation der vorliegende technische Report dient. Wie mit den vorhergegangenen nationalen IPv6 Gipfeln verfolgte der Deutsche IPv6-Rat auch mit dem 5. Gipfel, der unter dem Motto „IPv6- der Wachstumstreiber für die Deutsche Wirtschaft” stand, das Ziel, Einblicke in aktuelle Entwicklungen rund um den Einsatz von IPv6 zu geben. Unter anderem wurden die Vorzüge des neue Internetstandards IPv6 vorgestellt und über die Anwendung von IPv6 auf dem Massenmarkt, sowie den Einsatz von IPv6 in Unternehmen und in der öffentlichen Verwaltung referiert. Weitere Themen des Gipfels bezogen sich auf Aktionen und Bedingungen in Unternehmen und Privathaushalten, die für den Umstieg auf IPv6 notwendig sind und welche Erfahrungen dabei bereits gesammelt werden konnten. Neben Vorträgen des Bundesbeauftragten für Datenschutz Peter Schaar und des Geschäftsführers der Technik Telekom Deutschland GmbH, Bruno Jacobfeuerborn, wurden weiteren Beiträge hochrangiger Vertretern aus Politik, Wissenschaft und Wirtschaft präsentiert, die in diesem technischen Bericht zusammengestellt sind. / The 5th German IPv6 Summit took place at the Hasso Plattner Institute for Software System Engineering in Potsdam at November 29-30, 2012. This technical report is summarizing the talks and presentations and serves as a documentation of the summit. Like with previous IPv6 summits, the goal of this summit was to present current developments concerning the implementation of the new IPv6 technology from political and economic perspectives, as well as from a technological point of view. According to the motto "IPv6- der Wachstumstreiber für die Deutsche Wirtschaft", the advantages of the new Internet standards have been presented. Furthermore the application of IPv6 in industry, politics and administration has been discussed. The actions and procedures have been identified, which have to be applied for the change to IPv6 in industry and private households and gained experiences have been discussed. Besides presentations of the Federal Commissioner for Data Protection, Peter Schaar and Bruno Jacob Feuerborn, CTO at Deutsche Telekom, the summit was complemented by talks and presentations of high-ranking representatives from industry, government, and research.

Am 1. und 2. Dezember 2011 fand am Hasso-Plattner-Institut für Softwaresystemtechnik GmbH in Potsdam der 4. Deutsche IPv6 Gipfel 2011 statt, dessen Dokumentation der vorliegende technische Report dient. Wie mit den vorhergegangenen nationalen IPv6-Gipfeln verfolgte der Deutsche IPv6-Rat auch mit dem 4. Gipfel, der unter dem Motto „Online on the Road - Der neue Standard IPv6 als Treiber der mobilen Kommunikation” stand, das Ziel, Einblicke in aktuelle Entwicklungen rund um den Einsatz von IPv6 diesmal mit einem Fokus auf die automobile Vernetzung zu geben. Gleichzeitig wurde betont, den effizienten und flächendeckenden Umstieg auf IPv6 voranzutreiben, Erfahrungen mit dem Umstieg auf und dem Einsatz von IPv6 auszutauschen, Wirtschaft und öffentliche Verwaltung zu ermutigen und motivieren, IPv6-basierte Lösungen einzusetzen und das öffentliche Problembewusstsein für die Notwendigkeit des Umstiegs auf IPv6 zu erhöhen. Ehrengast war in diesem Jahr die EU-Kommissarin für die Digitale Agenda, Neelie Kroes deren Vortrag von weiteren Beiträgen hochrangiger Vertretern aus Politik, Wissenschaft und Wirtschaft ergänzt wurde. / This technical report is summarizing the talks and presentations of the 4th German IPv6 Summit 2011 at the Hasso Plattner Institute for Software System Engineering in Potsdam on December 1./2. 2011. The goal of this summit was to present current developments concerning the implementation of the new IPv6 technology from political and economic perspectives, as well as from a technological point of view. According to the motto 'Online on the Road - The New Technology Standard IPv6 as Driving Force for Mobile Communications" this year's focus was on automobile networking and communication. This year's guest of honor was EU commissioner for Digital Agenda Neelie Kroes. Besides her, the conference was complemented by talks and presentations of high-ranking representatives from industry, government, and research.

Univ., Diss.--Jena, 2000. / Literaturverz. S. 213 - 220.

Sedan den finanskris som uppstod år 2008 har ökade krav ställts beträffande säkerhet ochstabilitet inom den finansiella sektorn. Av den orsaken har etablerade aktörer, vilka omfattas avde alltmer extensiva regelverken, påförts ytterligare krav avseende exempelvis tillsyn ochlikviditet. De ökade säkerhetskraven har, i sin tur, tvingat berörda aktörer att agera merrestriktivt beträffande finansiell innovation och vid utvecklandet av nya finansiella lösningar. Den tekniska utvecklingen har möjliggjort för uppkomsten av nya typer av betaltjänster ochprodukter. Det har resulterat i att etablerade finansiella aktörer, under det senaste decenniet, harmött nya utmaningar i form av en ökad konkurrens från fintechbolag vilka, vid sidan avbefintliga regelverk, har utvecklat innovativa tjänster och produkter specialiserade inom ettspecifikt led inom kundkontaktskedjan. Med anledning av ikraftträdandet av det andrabetaltjänstdirektivet omfattas även fintechbolag av de bestämmelser som reglerarbetaltjänstmarknaden. Genom införandet av regelverket utökas omfattningen till att äveninbegripa leverantörer av kontoinformationstjänster och betalningsinitieringstjänster, så kalladetredjepartsleverantörer. Syftet med det andra betaltjänstdirektivet är bland annat att främjakonkurrens samt att effektivisera den finansiella marknaden. Samtidigt får inte den finansiellastabiliteten äventyras på bekostnad av ifrågavarande ändamål. För att främja finansiell innovation har vissa nationella tillsynsmyndigheter vidtagit olikaregleringsrelaterade åtgärder, såsom exempelvis en regulatorisk sandlåda, en innovationshubbeller ett innovationscenter. Med åtgärderna avses att med olika medel tillvarata den potentialsom fintech har att erbjuda finansmarknaden. Regleringsrelaterade åtgärder, vidtagna pånationell nivå, måste emellertid utvecklas och förhållas till gällande regelverk och får inte sättakonsumentskyddet på spel. I förevarande uppsats behandlas huruvida såväl det andra betaltjänstdirektivet som nationelltvidtagna regleringsrelaterade åtgärder förmår att främja tredjepartsleverantörersinnovationsförmåga på betaltjänstmarknaden, särskilt med beaktande av deras möjligheter attkonkurrera på den finansiella marknaden, utan att det sker på bekostnad av det finansiellasystemets stabilitet och säkerhet.

Safety is the main concern of the aviation industry. All Air Navigation Service Providers must have a Safety Management System (SMS) which states how safety is handled, promoted and prioritized. By developing Key Performance indicators (KPIs), it is possible to quantify the effectiveness of a SMS, discover potential flaws and improvement measures. This thesis identifies principles behind the SMS, the development of KPIs and suggest potential KPIs for the Swedish air navigation service provider LFVs’ SMS. A literature study was performed and organisation specific documents were analysed to develop potential KPIs within the areas timely compliance with international obligations, competency and adoption and sharing of best practices based on an EASA questionnaire. This work presents a set of 27 performance indicators and recommends 6 as potential KPIs for the three areas together. The KPIs are developed specifically for LFV but could be applicable for other organisations with similar SMS structure and processes. They should be analysed within the organisation and, potentially, have thresholds set before implementation.

A terceirização e a primarização constituem estratégias de gestão que vem sendo adotadas por empresas florestais brasileiras. Entretanto, apesar de sua crescente utilização, suas diferenças em termos técnicos, econômicos e estratégicos, tais práticas não têm sido objeto de muitos estudos no Brasil, principalmente no que se refere ao setor florestal. Em virtude dessa realidade, o objetivo principal desta pesquisa foi comparar os modelos terceirizados e primarizados dos processos de produção de mudas, formação florestal, colheita e carregamento de madeira, em florestas plantadas, avaliando riscos, oportunidades e recomendando melhores alternativas segundo a percepção ou o ponto de vista dos principais envolvidos, ou seja, a empresa florestal contratante e o prestador de serviços. Para a realização das análises financeiras e de custos dos processos florestais abrangidos no estudo foram utilizadas informações levantadas junto a empresas prestadoras de serviços florestais localizadas no extremo sul da Bahia, cedidas pela Cia Suzano Papel e Celulose, Unidade Mucuri-BA (contratante) e mais outras cotações realizadas com diferentes fornecedores de materiais, mão-de-obra, serviços e insumos. A partir das análises, verificou-se que os processos florestais produção de mudas (com viveiro próprio) e carregamento de madeira, quando terceirizados, apresentaram custo operacional menor do que quando primarizados. Já os processos formação florestal e colheita mecanizada, quando primarizados com a aquisição de máquinas, resultaram em custo operacional menor do que quando terceirizados. Porém, em virtude da necessidade de investimento para aquisição de equipamentos e estruturas, o resultado da análise financeira de todos os processos primarizados tornou-se negativo (VPL < 0). Constatou-se também que os principais fatores contrários à primarização foram: custo com mão-de-obra (significativamente maior para a atividade primarizada), custo com estrutura de apoio e remuneração do capital investido. Já os principais fatores favoráveis à primarização foram: carga de taxas e impostos incidentes sobre o custo do serviço de terceiros e a margem de lucro aplicada pelo prestador de serviço. Ainda que apresente resultados financeiros negativos, a primarização das atividades florestais pode trazer outros benefícios, viabilizando-a estratégica e até economicamente, possibilitando o livre-arbítrio ao administrador quanto à melhor forma de gestão de acordo com a sua realidade e necessidade dentro do mercado. Palavras-chave: Operaçõ / The Outsourcing and the Primarization constitute management strategies been used by Brazilians forest companies. However, although its use is increasing, technical, economics and strategy terms are not being studied in Brazil, mainly on the forestry sector. Therefore, the principal goal on this research was to compare Outsourcing and Primarization Models including the process of seedlings production, forest formation, harvest and loading for planted forest, evaluating risk, opportunity and recommendation about better practices by the perception or point of view of the forest company and the service provider. The database for realize the financial and cost analyses from forest processes came from forest services providers, in the Extreme South of Bahia Estate, and Suzano Pulp and Paper Company (contractor). Seedling production, with own nursery, and wood loading presented lower operational costs when done by services providers. The costs of forest formation and harvest processes, when done by the contractor, including machines acquisition, were lower than the same operations done by services providers. However, because of necessary investment for machinery and structure acquisition, the financial analysis of all primarized processes resulted negative (NPV < 0). The main negative factors were labor cost (significantly higher for primarized activities) and the cost of payment for invested capital. The main factors favoring the primarization were taxes paid by services providers and the profit margin earned by them.

<p>This thesis puts forward a new solution to provide the reliable network to the Internet Service Provider (ISP). This study mainly focuses on the ISPs network to provide reliability and the load balancing. It offers a guide line for the best reliable solution to the ISPs, individual organizations or other types of service providers which are engaged in providing reliable communications to their subscribers. These reliable services may be real time communications which include weather forecasts, tracking systems, online Internet protocol TV (IPTV) programs and many other ISPs services which are totally depend on the reliable network.</p><p>With the appearance and expansion of Internet subscribers all over the world, ISPs services are becoming more popular. The rapid increase of connection-demand and highly traffic network is the main reason behind the need to scale reliable network. To offer better solutions, a new theoretical and practical approach should be considered that can cover the reliable network.</p><p>The suggested network structure monitors the links, spreads the network traffic with multiple devices and takes a backup (redundant) link automatically when changes occur in the network topology. In order to support the redundancy, load balancing and reduce the failover time, the hot standby routing protocol (HSRP) is implemented on the suggested network. As we have analyzed that in any network, scalability bringing to raised the network traffic broadcast issue. Broadcast storms can be prevented by setting threshold values of traffic-filters. The threshold level helps to control broadcast traffic in networks.</p><p>With regard to suggested solutions, it is necessary to observe the limitations and advantages of the recommended reliable network structure. Therefore, this research will include the advantages and limitations of the techniques used to offer ISP services such as scalability, security and IPv6.</p>

User desire for ubiquitous applications on-board a vehicle motivates the necessity for Network Mobility (NEMO) solutions for Vehicular Ad-Hoc Networks (VANETs). Due to the dynamic topology of VANETs, this approach incurs excessive infrastructure cost to maintain stable connectivity and support these applications. Our solution to this problem is focused on a novel NEMO-based Network Architecture where vehicles are the main network infrastructure. Within this Architecture, we present a Network Criticality-based clustering algorithm, which adapts to mobility changes to form stable self-organizing clusters of vehicles and dynamically builds on vehicle clusters to form more stable Mobile Networks. Simulation results show that the proposed method provides more stable clusters, lower handoffs and better connectivity compared to popular density-based vehicle clustering methods. In addition, they confirm the validity of the proposed Network Architecture. The proposed method is also robust to channel error and exhibits better performance when the heterogeneity of vehicles is exploited.