A digital resource harvesting approach for distributed heterogeneous repositories

OAI-PMH has been widely adopted as a simple solution for harvesting the metadata of different repositories automatically. Harvesting digital resources described by the metadata is outside of the scope of the OAI-PMH data model. However, there are some growing needs to make resources, not only metadata, harvestable by an interoperable manner in the distributed heterogeneous environments. In this paper, we present the new approach of digital resource harvesting, which uses Message Queue-based communication mechanism as the datastream transfer method, and ensures the request and response message specification built on METS during the course of data transfer. The approach can harvest digital resources solely or synergically with OAI-PMH. A case study about this approach applied in CALIS_ETD digital library will be introduced in the end.