Digital Object Identifier (DOI) Help
The Digital Object Identifier (DOI) is an identification system for intellectual property in the digital environment. Developed by the International DOI Foundation on behalf of the publishing industry, its goals are to provide a framework for managing intellectual content, link customers with publishers, facilitate electronic commerce, and enable automated copyright management.
Using DOIs: An Overview
Publishing on the Internet requires new tools for managing content. Where traditional printed texts such as books and journals provided a title page or a cover for specific identifying information, digital content needs its own form of unique identifier. This is important for both internal management of content within a publishing house and for dissemination on electronic networks.
In the fast-changing world of electronic publishing, there is the added problem that ownership of information changes, and location of electronic files changes frequently over the life of a work. Technology is needed that permits an identifier to remain persistent although the links to rights holders may vary with time and place.
The network environment creates an expectation among users that resources can be linked and that these links should be stable. The DOI system provides a way to identify related materials and to link the reader or user of content to them. DOI has wide applicability to all forms of intellectual content and can therefore be applied to all forms of related materials, such as articles, books, classroom exercises, supporting data, videos, electronic files, and so on.
DOI provides a basis for work now in progress to develop automated means of processing routine transactions such as document retrieval, clearinghouse payments, and licensing. Publishers and users are being encouraged to experiment with DOI usage, and to commonly develop guidelines for DOI scope and rules for usage.
The DOI System and how it works
The DOI system has two main parts (the identifier, and a directory system) and a third logical component, a database.
The identifier: The DOI, is made up of two components. The first element — the prefix — is assigned to the publisher by a registration agency. Eventually, there may be multiple registration agencies to serve separate geographical regions or for each intellectual property sector (such as text publishing, photographs, music, software, etc.). However, at this stage there is only one registration agency and Directory Manager. Prefixes all begin with 10 to designate the DOI directory manager, followed by a number designating the publisher who will be depositing the individual DOIs, which ensures that a publisher can designate its own DOIs without fear of creating duplicate numbers. Publishers may choose to request a prefix for each imprint or product line, or may use a single prefix.
The second element, following a slash mark, is the suffix. This is the designation assigned by the publisher to the specific content being identified. Many publishers have elected to use recognized existing international standards for their suffixes when such a standard applies to the object being identified (e.g., ISBN for a book), but may alternatively choose to use an internal code. In use, the DOI identifier is an opaque string without intelligent meaning other than as an identifier.
The suffix can follow any system of the publisher’s choosing, and be assigned to objects of any size — book, article, abstract, chart — or any file type — text, audio, video, image or software. An object (book) may have one DOI, and a component within that object (chapter) may have another DOI. The publisher decides the level or “granularity” of identification based on the nature of objects sold and distributed over the Internet. The suffix can be as simple as a sequential number or a publisher’s own internal numbering system.
The directory: The power of the DOI system is its function as a routing or “resolution” system. Because digital content may change ownership or location over the course of its useful life, the DOI system uses a central directory. When a user clicks on a DOI, a message is sent to the central directory where the current web address associated with that DOI appears. This location is sent back to the user’s Internet browser with a special message telling the system to “go to this particular Internet address.” In a split second the user sees a “response screen” — a Web page — on which the publisher offers the reader either the content itself, or, if not, then further information about the object, and information on how to obtain it. When the object is moved to a new server or the copyright holder sells the product line to another company, one change is recorded in the directory and all subsequent readers will be sent to the new site. The DOI remains reliable and accurate because the link to the associated information or source of the content is so easily and efficiently changed. The underlying technology used in the DOI system is optimised for speed, efficiency, and persistence.
The database: Information about the object identified is maintained by the publisher. However it is planned that the DOI system will also collect some minimum level of associated metadata to enable provision of automated efficient services such as look-up of DOIs from bibliographic data, citation linking, and so forth. Thus information about the object identified (metadata) might be distributed over several databases. It might include the actual content or the information on where and how to obtain the content or other related data. From these database systems is generated the information that the user has access to in response to a DOI query, forming the third component of the DOI system.
The DOI can also serve as an agent. In the future, the DOI will also be used to automate transactions. The DOI is being further developed to incorporate functionality which could enable the user to associate a function with the DOI.