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Technical Information for the 1998/99 Competition > Guidelines and Resources Prepared for Applicants > Handle Server: More on Handles and Naming Authorities |
Overview | More on Handles and Naming Authorities | A Global System of Handle Servers
Any form of Uniform Resource Name (URN) has three properties:
URN:hdl: naming authority / name
Each naming authority is associated with a home handle server. After an initial phase, the Library will have a local handle server under its own control.
The name portion of the handle has no meaning to the handle server; names can be generated by any conventions that guarantee uniqueness within the naming authority. The general form for handles for items in NDLP collections will consist of a collection or aggregate identifier followed by an identifier for the item.
Today's WWW browsers use Uniform Resource Locators which point to files on particular computers. A browser (or any other computer program) that supports URNs will present a location-independent URN to a URN server for resolution into a URL or some other form of locator. CNRI has developed software for a Handle System, which is being incorporated into some prototype digital libraries, including a prototype repository for American Memory. When a resource is moved, its record in the handle server is modified. Users of the handle will be unaware of the move. Links to the handle will automatically access the resource from its new location.
In comparison with some other candidate schemes for Uniform Resource Names, the CNRI system emphasizes persistence. There is no formal relationship between the scheme's naming authorities and existing network-related names such as Internet domain names, which may change if two publishers merge. Once an item has been named by an authority, its handle can be permanent. The naming authority can move its operations across the country or round the world without a need to alter handles. If an authority goes out of business and ceases to create new handles, the handles it had registered can remain in the system.
The Global Handle Registry will not permit the creation of duplicate naming authorities. Whenever a naming authority creates a new handle, the handle is checked for uniqueness.
NOTE: Links to resources outside the Library of Congress are to URLs that were active when this set of archived documentation was actively maintained. Some links may no longer be active because resources have been removed. If a link is active, the resource may have changed substantially since the documentation was created. No attempt will be made to trace the linked resources or to suppress bad links. The URLs are being retained for their value as historical evidence.
In this article, based on a presentation at the April 1995 meeting of the Coalition of Networked Information (CNI), Bill Arms of CNRI introduces the handle-server and repository in simple terms and diagrams.
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Content updated: 1998-05-04
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