2.16. OAI Support

2.16. OAI Support
The Open Archives Initiative(開放典藏計劃) [http://www.openarchives.org/] has developed a protocol for metadata harvesting(後設資料的擷取)[http://www.openarchives.org/OAI/openarchivesprotocol.html]. This allows sites to programmatically retrieve or 'harvest' the metadata from several sources, and offer services using that metadata, such as indexing or linking services. Such
a service could allow users to access information from a large number of sites from one place.
DSpace exposes(公開) the Dublin Core metadata for items that are publicly (anonymously) accessible. Additionally, the collection structure is also exposed via the OAI protocol's 'sets' mechanism. OCLC's open source OAICat [http:// www.oclc.org/research/software/oai/cat.shtm] framework is used to provide this functionality. You can also configure the OAI service to make use of any crosswalk plugin to offer additional metadata formats, such as MODS.
DSpace's OAI service does support the exposing of deletion information for withdrawn items(制定項目), but not for items that are 'expunged' (see above). DSpace also supports OAI-PMH resumption tokens.