There are two main challenges for flexible service provisioning on top of today's Internet. First the end-to-end networking paradigm which is based on a service and data unaware transport, and secondly a lack of high level communication abstractions.With this thesis we approach both challenges. To address the first point we propose a methodology to integrate the Network Provider into the process of service provisioning. The introduced cooperative service provisioning (CSP) enables an interaction between Service Provider, Network Provider and Client. CSP can be applied in classical Provider as well as novel Peerto-Peer scenarios.To address the second point, we adopt a Service Overlay approach. A new method based on the extension of Distributed Hash Tables (DHTs) is proposed to realise a distributed control plane for a decentral and reactive creation of Service Overlays. To archive this, a methodology to reduce Service Overlay related routing problems to search problems was developed. With regard to the required Quality of Service (QoS) measurements, the thesis focuses on scalable and time efficient estimation techniques. As a result, two new delay prediction schemes have been developed which improve estimation accuracy when compared to the state of the art.Furthermore, a novel approach to bandwidth estimation is investigated. It combines methods from landmark based delay estimation with a transformation step and has favourable estimation accuracy.

Wittgenstein's conception of logical and conceptual truth is often thought to rival that of the logical positivists. This paper argues that there are important respects in which these conceptions complement each other. Analyticity, in the positivists' sense, coincides, not with Wittgenstein's notion of a grammatical proposition, but rather with his notion of a tautology. Grammatical propositions can usually be construed as analyticity postulates in Carnap's sense of the term. This account of grammatical and analytic propositions will be illustrated by appeal to logical, conceptual and arithmetic truths. Its consequences for an analysis of corresponding modal notions will be indicated.

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