Catalogue: graph representation of file relations for a globally distributed environment

Text-based search engines are widely used to find files in the Internet. However, the users require to understand contexts existing in files and notice appropriate keywords even if the users do not have deep insights of the topic. In addition, text-based search engines require exhaustive search to make keyword indexes. This paper proposes the concept of catalogue that represents relations among files based on grouping and associating by a directed graph. Grouping of files by a catalogue without any text label lets us notice some relations represented by the catalogue. Moreover, a directed graph within a catalogue which associates files can express more detailed relations. We design catalogue system that stores and shares catalogues globally in a distributed and autonomous way. Generalized graph expression of catalogues shared over the Internet bridges any owners, types, and fields of files as long as the files share a same relation. Various services such as digital museums and digital archives are expected to work on top of the shared catalogues.