Building the InfoBus:
A Review of Technical Choices in the Stanford Digital Library Project

Andreas Paepcke
Stanford University


Our approach to digital library infrastructure is based on the premise that DLs will not just be online catalogs and collections, but that they will be made up of geographically wide-spread, interoperating services that support users in their tasks. Our infrastructure, called the 'InfoBus' is based on CORBA distributed object technology. We build proxy objects to provide uniform interfaces to online services that present different interaction models and access protocols. For this talk, we will select several aspects of our digital library, and discuss the tradeoffs we made. First, we explain how we distributed user interface functionality among clients and services. Second, we present our experience with an object-centric information retrieval protocol we developed for the project. Third, we explain how metadata plays an important role in DL interoperability, and why existing metadata representations fall short when used for digital libraries. Finally, we will explain how user traditions and expectations have impacted our designs at a deeply technical level.