Improving the real-time performance of heterogeneous extremely large datasets

The POWDER protocol is a Semantic Web technology --and W3C Recommendation- that takes advantage of natural groupings of URIs, as identifiers as well as navigational paths, to annotate all the resources in a regular expression-delineated sub-space of the URI space. POWDER was designed as a mechanism for accreditation, trustmarking and resource discovery, emphasizing the publishing of attributed metadata by third parties and trusted authorities. However, its versatility allows the application of POWDER in different use cases such as repository compression. In this paper, we present the POWDER protocol, briefly discuss current implementations and use cases and present how POWDER can be implemented over existing well-tested and robust semantic storage systems. Furthermore, we discuss a novel solution for the scalable storing data summaries in the form of metadata for the purposes of source selection and source schema coordination in large-scale, heterogeneous federations of semantic querying endpoints. Our solution takes advantage of POWDER's ability to exploit naming conventions and other natural groupings of URIs in order to compress instance-level metadata about the nodes of a data service federation, especially in situations where URI hashing cannot be used to efficiently resolve the sources that hold statements regarding a given URI resource.