IJDL special issue on complex digital objects: Guest editors' introduction

Abstract

Although the Web of today looks very different from the Web of 10 years ago, digital library (DL) file formats still look much the same. Using terminology from the Open Archival Information System (OAIS), the submission information packages (SIPs) and archival information packages (AIPs) were frequently the same application specific formats of the dissemination information packages (DIPs). Driven by the proliferation of enabling technologies such as XML, Resource Description Format (RDF) and Dublin Core, there has been increasing interest in the DL community to use complex digital objects: objects that aggregate data, metadata and sometimes services into a single, logical digital entity. For example, instead of just a bare PDF file, a complex object could aggregate the PDF, the descriptive metadata (perhaps in multiple formats), provenance and rights statements and links to format conversion services. While the end-user continues to receive the PDF, DLs would ingest and exchange the complex digital object, building extended services based on the additional encapsulated and aggregated data. In much the same way that metadata formats arise from different communities, so have complex digital objects. In the realm of scientific and high-performance computing, data formats such as NetCDF [1], HDF [2], SmartFiles [3] and ELFS [4] have been in widespread use. In the commercial content provider industry, complex objects can be traced to the persistent stores of object-oriented databases