Uniform Resource Identifier

Architecture of the World Wide Web (Vol 1)

graybeal — Thu, 22 Mar 2007 06:07:00 -0700

This document by W3C (the World Wide Web Consortium) presents the architecture of the World Wide Web. It extensively describes the purpose and use of Universal Resource Identifiers. It describes their relationship to the resources they identify, and how URIs and other web resources are resolved by the agents (servers and clients) to provide the desired content. This document includes many best practices for the use of URIs.

Archival Resource Keys

graybeal — Thu, 22 Mar 2007 06:51:00 -0700

This persistent digital object identifer technology is currently being implemented and tested by the California Digital Library (CDL) for collections that it manages. The ARK identifier is a specially constructed, globally unique, actionable URL designed to be without semantic association to the related item. Each ARK links end-users to three things:

Citations - They're Not Just for Publications Anymore

carynn — Mon, 09 Jun 2008 14:37:12 -0700

By definition, metadata exists to describe data or information. Descriptive metadata enables appropriate use, and facilitates re-use of data. Once data has been discovered and used, it should be cited. Publications frequently reference data sets, but the question remains - how should authors cite data?

As part of its Data Policy, the International Polar Year (IPY) indicates

Community Updates Team

Cool URIs Don't Change

graybeal — Tue, 27 Nov 2007 13:57:00 -0800

This document argues for the feasibility and value of maintaining Uniform Resource Identifiers (URIs) indefinitely. It finds the both Universal Resource Names (URNs) and the familiar Universal Resource Locators (URLs) should remain the same (and in the case of URLs, resolvable) indefinitely, through good design and implementation practices.

Encoding URIs in ISO 19139

luisBer — Thu, 10 Jan 2008 18:07:00 -0800

Motivation

Ontologies Team

GML Object Identifiers

graybeal — Tue, 27 Nov 2007 13:57:00 -0800

This document by the SEE GRID community describes GML object identifiers (providing many examples)/

IANA Namespaces for URNs

graybeal — Thu, 22 Mar 2007 05:44:00 -0700

This IANA registry provides links to the document that describes each URN scheme.

Identifying Web Resources

graybeal — Thu, 22 Mar 2007 06:50:00 -0700

This discussion on the SeeGRID pages provides considerable context for the question of web identifiers.

IETF Internet Engineering Task Force, RFC 3986: Uniform Resource Identifier (URI)

luisBer — Fri, 07 Dec 2007 08:17:00 -0800

IETF Internet Engineering Task Force, RFC 3986: Uniform Resource Identifier (URI): Generic Syntax, in T. Berners-Lee, F. R. and L. Masinter, eds., 2005, http://www.ietf.org/rfc/rfc3986.txt.

Implementing Persistent Identifiers

graybeal — Tue, 27 Nov 2007 13:46:00 -0800

This document, by Hans-Werner Hilse and Jochen Kothe in November 2006, is a fairly complete reference to key issues on Persistent identifiers. It discusses various types of identifiers including Handles, Digital Object Identifiers (DOIs), Archival Resource Keys (ARKs), Persistent Uniform Resource Locators (PURLs), Uniform Resource Names (URNs), National Bibliography Numbers (NBNs), and the OpenURLs. Examples and references are provided for each type of identifier.

International Resource Identifiers (IRIs)

graybeal — Tue, 27 Nov 2007 13:54:00 -0800

International Resource Identifiers may replace URIs in a lot of Semantic Web activities. URLs are limited since the construct can use only ASCII characters, while IRIs can contain characters from the Universal Character Set ISO/IEC 10646.

MMI Guide for Ontology Providers

graybeal — Sun, 02 Nov 2008 17:34:25 -0800

MMI Guide for Ontology Providers
Marine Metadata Interoperability Project
Version: November 2, 2008

Ontologies Team

OGC Best Practices for URNs

graybeal — Thu, 22 Mar 2007 05:43:00 -0700

a best practice document that describes a standard mechanism for using URNs to reference various abstract concepts and resources, especially those relating to coordinate reference systems (e.g. datums, ellipsoids, prime meridians, etc). The URNs follow the format "urn:ogc:def:crs:EPSG:6.3:26986" (for a CRS defined in the EPSG codespace, in this example)

Persistent Uniform Resource Locators (PURL)

graybeal — Thu, 22 Mar 2007 07:00:00 -0700

A PURL provides a reference to an intermediate resolution service. The PURL resolution service associates the PURL with the actual URL and returns that URL to the client. A PURL has three parts: (1) a protocol, (2) a resolver address, and (3) a name. A PURL looks like any of the following:

Term Resolution Discussion

graybeal — Thu, 22 Mar 2007 06:54:00 -0700

This discussion on the SeeGRID pages provides a number of options to consider when trying to define resolvable unique terms.

The Handle System Digital Object Architecture

graybeal — Thu, 22 Mar 2007 06:50:00 -0700

This system provides an architecture, upon which other systems can be built, for handling and referencing digital objects. It is a fee-based service to offset the costs of its operation.

Universally Unique Identifiers (UUIDs)

graybeal — Tue, 26 Feb 2008 18:25:00 -0800

A Universally Unique Identifier is a code (sequence of characters or binary value) which is generated on request, and is expected to not be duplicated across all computer applications. It is an important capability when trying to refer to objects uniquely, that is, by a unique reference number. This important topic is discussed in many places, but a reasonable overview with many references is at Wikipedia.

URI Generic Syntax (IETF)

graybeal — Thu, 22 Mar 2007 05:45:00 -0700

Original Request for Comment document of IETF describing URIs. Includes the following: ...although many URI schemes (e.g. URLs) are named after protocols, this does not imply that use of these URIs will result in access to the resource via the named protocol. URIs are often used simply for the sake of identification...

URIs: What, Why, and How?

luisBer — Fri, 07 Dec 2007 08:00:00 -0800

Definition of URIs

A URI, or Unique Resource Identifier, is a Web naming/addressing technology that uses short strings to refer to resources in the Web. These resources could be Web Documents, services, electronic mailboxes, images, downloadable files, or other electronic entities. URI encompasses both URLs (Universe Resource Locators) and URNs (Uniform Resource Names).

Ontologies Team

URN Namespace for OGC

graybeal — Tue, 27 Nov 2007 13:48:00 -0800

Document by Carl Reed on the URN namespace for OGC.