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But PURL are actually persistent locators ? that is after all their name. A PURL does not offer any service except that of resolution to its destination. There is no way to get metadata about the object, and no way to determine an institutions commitment to maintain a PURL. No way to store alternate, or backup URL?s, and no way to provide context specific resolution.
Handles
http://www.handle.net/introduction.html
The LOC has this writeup on Handles: http://lcweb2.loc.gov/ammem/award/docs/h-s2.html
http://www.handle.net/rfc/rfc3650.html
http://www.handle.net/rfc/rfc3651.html
DOI?s ? I think DOI?s are an implementation of handles, but commercially, so each DOI costs money. Other than that, I don?t see any difference between doi?s and handles.
To quote:
The DOI System is an application of the Handle System to intellectual property. The DOI is managed and developed by the International DOI Foundation, a not-for-profit membership organization. The DOI system adds to the Handle System an approach based on structured associated metadata; policies regarding scope and application; procedures for ensuring consistency and quality control across applications; business models; and specific application tools. Initial implementations are now being supplemented by increasingly sophisticated value-added tools for metadata management and content management, which will use the Handle System multiple resolution function. More information is available in the DOI Handbook.
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