Public government data refers to documents and proceedings which are freely available and accessible. Repositories facilitate the collection, publishing and distribution of data in a centralized and possibly standardized way. Metadata is used to catalog and organize the provided data. The operationality and interoperability depends on the metadata quality. In order to measure the efficiency of a repository the metadata quality needs to be quantified. Quality assessment is considered to be most reliable when carried out by a human expert. This approach, however, is not always feasible. Hence, an automatic assessment of the quality of metadata should be pursued.Proposed metrics from the field of metadata quality assessment are taken, implemented and applied to three public government data repositories, namely GovData.de (Germany), data.gov.uk (United Kingdom) and publicdata.eu (Europe). Five quality metrics were applied: completeness, weighted completeness, accuracy, richness of information and accessibility. The metrics and their implementation will be discussed in detail and the results evaluated.

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This chapter covers the scientific background for the Service Level Module of the Unified Service Description Language (USDL). In addition to general service level concepts, we expand on two specific service level fields: security and trust. For that end we first review the state of the art in service level modeling, then we explain the design of the Service Level Module and position it among the rest of USDL. For security, two possible perspectives, a high level business view and a low level engineering approach, are introduced. With regards to trust, USDL is suitable to specify how a service can be rated by its consumers and to ensure that ratings of competing services are comparable, and hence to determine trustworthiness. Additionally, we present a description of non-security-related elements that can be exploited for trust estimation.

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We present a mechanism for reliable multicast based on autonomic principles (AutoRM). So-called Beamon nodes exchange information in a peer-to-peer manner, deriving a subjective view of the environment. Applications connect to a Beamon network to participate in reliable communication within groups they declare to be joined to. This short paper describes the general AutoRM concepts, the architecture and protocols used between application and Beamon, as well as between the nodes themselves.