Christoph Ringelstein

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The processing of data is often restricted by contractual and legal requirements for protecting privacy and IPRs. Policies provide means to control how and by whom data is processed. Conditions of policies may depend on the previous processing of the data. However, existing policy languages do not provide means to express such conditions. In this work we(More)
Die Arbeitsberichte aus dem Fachbereich Informatik dienen der Darstellung vorläufiger Ergebnisse, die in der Regel noch für spätere Veröffentlichungen überarbeitet werden. Die Autoren sind deshalb für kritische Hinweise dankbar. Alle Rechte vorbehalten, insbesondere die der Übersetzung, des Nachdruckes, des Vortrags, der Entnahme von Abbildungen und(More)
Service-oriented systems facilitate business workflows to span multiple organizations (e.g. by means of Web services). As a side effect, data may be more easily transferred over organizational boundaries. Thus, privacy issues arise. At the same time, there are personal, business and legal requirements for protecting privacy and IPR and allowing customers to(More)
With novel centralized information management systems, users benefit from collective data organization. Centraliza-tion, however, also imposes privacy and availability constraints. With this work we present SEA, a semantic exchange architecture for distributed information management that employs Peer-to-Peer networking, social information management, and(More)
1 ABSTRACT Web services are software components that are – in general – distributed over multiple organizations. They provide functionality without showing implementation details for the purpose of abstracting from implementation as well as for the purpose of hiding private, i.e. organization-internal, processes. Nevertheless, to use a web service one must(More)