Exposure
The access continuum on its own is not enough to ensure the benefits of open
access. The contents of the repository also need to be exposed and discoverable.
This can be via a range of techniques: search engine spidering, the Open Archives
Initiative Protocol for Metadata Harvesting (OAI-PMH), RSS (Really Simple
Syndication – often used for podcast and blog alerting services) feeds, and/or
SRU/SRW (a search protocol designed as the successor to Z39.50) access through
federated search techniques. At one end of this continuum, there is limited or no
exposure to such harvesting software, meaning that even data objects with no
access restrictions are unlikely to be discovered. At the other end of this continuum,
the contents of repositories (such as the ARROW repositories) are exposed using a
range of technologies to provide the maximum accessibility.