Uniform Resource Identifier (URI)

Information Systems and the World Wide Web

International School of New Media
University of Lübeck

Erik Wilde, UC Berkeley School of Information
2007-01-02
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Abstract

A Uniform Resource Identifier (URI) identifies a resource in the context of the Web. A URI has several parts, most generally speaking a scheme (which indicates the way resources can be accessed), and a scheme-specific part. Rather than exposing a file system or similar resources through URIs, the namespace of a set of resources on the Web should be designed and maintained. This way, URIs can be used in a way which breaks fewer links by keeping URIs stable even when a Web site is completely redesigned and uses a different technology in its new incarnation.

URIs and URLs

Outline (Uniform Resource Identifier (URI))

  1. Uniform Resource Identifier (URI) [8]
  2. URI Namespaces [3]
  3. Cool URIs don't change [3]
  4. Conclusions [1]

Resource Identification

URI Schemes

URI = scheme ":" hier-part [ "?" query ] [ "#" fragment ]
[...] the URI syntax is a federated and extensible naming system wherein each scheme's specification may further restrict the syntax and semantics of identifiers using that scheme.

Uniform Resource Identifier (URI): Generic Syntax, RFC 3986, January 2005

Query Information

The query component contains non-hierarchical data that, along with data in the path component [...], serves to identify a resource within the scope of the URI's scheme and naming authority [...].

Uniform Resource Identifier (URI): Generic Syntax, RFC 3986, January 2005

Processing URIs

Resources vs. Representations

Bad Service

What's Bad?

Popular Screen Resolutions

Outline (URI Namespaces)

  1. Uniform Resource Identifier (URI) [8]
  2. URI Namespaces [3]
  3. Cool URIs don't change [3]
  4. Conclusions [1]

URI Design

Web Site Structure

URIs vs. File Systems

Outline (Cool URIs don't change)

  1. Uniform Resource Identifier (URI) [8]
  2. URI Namespaces [3]
  3. Cool URIs don't change [3]
  4. Conclusions [1]

Persistent URIs

URIs as Interfaces

Generic Links

Outline (Conclusions)

  1. Uniform Resource Identifier (URI) [8]
  2. URI Namespaces [3]
  3. Cool URIs don't change [3]
  4. Conclusions [1]

Handle With Care