URI-related RFC's and Documents

A Framework for Identifying, Locating, and Describing Networked Information Resources,
Clifford Lynch, March 1993.

As networked information resources proliferate on the Internet, systematic, standard means for identifying, locating, and describing these resources become increasingly necessary. While motivations for developing such schemes have been diverse, there are at least three major classes of applications that have been driving developments. First, the library community needs to extend traditional descriptive catalog practices to networked resources -- in essence, to permit bibliographic description and control of such resources in order to incorporate them integrally into library collections (in the sense that libraries are shifting from collections to access, and increasingly view their catalogs and other databases as bibliographies of materials to which they are prepared to provide, and perhaps subsidize, access) and to improve access to them. As networked information resources become critical to scholarship and research, and come to represent significant investments by institutions, it also becomes essential to apply the practices of information management to this new class of resources.

Universal Resource Identifiers in WWW: A Unifying Syntax for the Expression of Names and Addresses of Objects on the Network as used in the World-Wide Web (RFC 1630),
T. Berners-Lee, June 1994.

This document defines the syntax used by the World-Wide Web initiative to encode the names and addresses of objects on the Internet. The web is considered to include objects accessed using an extendable number of protocols, existing, invented for the web itself, or to be invented in the future. Access instructions for an individual object under a given protocol are encoded into forms of address string. Other protocols allow the use of object names of various forms. In order to abstract the idea of a generic object, the web needs the concepts of the universal set of objects, and of the universal set of names or addresses of objects.

A Vision of an Integrated Internet Information Service (RFC 1727),
C. Weider, P. Deutsch, December 1994.

This paper lays out a vision of how Internet information services might be integrated over the next few years, and discusses in some detail what steps will be needed to achieve this integration.

Resource Transponders (RFC 1728),
C. Weider, 12/16/1994.

Although a number of systems have been created in the last several years to provide resource location and navigation on the Internet, the information contained in these systems must be maintained and updated by hand. This paper describes an automatic mechanism, the resource transponder, for maintaining resource location information.

Functional Recommendations for Internet Resource Locators (RFC 1736),
J. Kunze, February 1995.

This document specifies a minimum set of requirements for Internet resource locators, which convey location and access information for resources. Typical examples of resources include network accessible documents, WAIS databases, FTP servers, and Telnet destinations.

Functional Requirements for Uniform Resource Names (RFC 1737),
K. Sollins, L. Masinter, December 1994.

This document specifies a minimum set of requirements for a kind of Internet resource identifier known as Uniform Resource Names (URNs). URNs fit within a larger Internet information architecture, which in turn is composed of, additionally, Uniform Resource Characteristics (URCs), and Uniform Resource Locators (URLs). URNs are used for identification, URCs for including meta-information, and URLs for locating or finding resources. It is provided as a basis for evaluating standards for URNs. The discussions of this work have occurred on the mailing list uri@bunyip.com and at the URI Working Group sessions of the IETF.

Uniform Resource Locators (URL) (RFC 1738),
T. Berners-Lee, L. Masinter, M. McCahill, December 1994. Updated by RFC 3986.

This document specifies a Uniform Resource Locator (URL), the syntax and semantics of formalized information for location and access of resources via the Internet.

Relative Uniform Resource Locators (RFC 1808),
R. Fielding, June 1995, Obsoleted by RFC 3986.

A Uniform Resource Locator (URL) is a compact representation of the location and access method for a resource available via the Internet. When embedded within a base document, a URL in its absolute form may contain a great deal of information which is already known from the context of that base document's retrieval, including the scheme, network location, and parts of the url-path. In situations where the base URL is well-defined and known to the parser (human or machine), it is useful to be able to embed URL references which inherit that context rather than re-specifying it in every instance. This document defines the syntax and semantics for such Relative Uniform Resource Locators.

An LDAP URL Format (RFC 1959),
T. Howes and M. Smith, June 1996.

LDAP is the Lightweight Directory Access Protocol, defined in [1] and [2]. This document describes a format for an LDAP Uniform Resource Locator which will allow Internet clients to have direct access to the LDAP protocol. While LDAP currently is used only as a front end to the X.500 directory, the URL format described here is general enough to handle the case of stand-alone LDAP servers (i.e., LDAP servers not back-ended by X.500).

Uniform Resource Locators for Z39.50 (RFC 2056),
R. Denenberg, J. Kunze, D. Lynch, November 1996.

Z39.50 is an information retrieval protocol that does not fit neatly into a retrieval model designed primarily around the stateless fetch of data. Instead, it models a general user inquiry as a session-oriented, multi-step task, any step of which may be suspended temporarily while the server requests additional parameters from the client before continuing.

Content-ID and Message-ID Uniform Resource Locators (RFC 2111),
E. Levinson, March 1997. Obsoleted by RFC 2392.

The Uniform Resource Locator (URL) schemes, "cid:" and "mid:" allow references to messages and the body parts of messages. For example, within a single multipart message, one HTML body part might include embedded references to other parts of the same message. This document is a product of the MIME Encapsulation of Aggregate HTML Documents Working Group of the IETF.

VEMMI URL Specification (RFC 2122),
D. Mavrakis, H. Layec, K. Kartmann, March 1997.

A new URL scheme, "vemmi" is defined. It allows VEMMI client software and VEMMI terminals to connect to multimedia interactive services compliant to the VEMMI standard (Enhanced Man-Machine Interface for Videotex and Multimedia/Hypermedia Information Retrieval Services), sometimes abbreviated as "VErsatile MultiMedia Interface".

URN Syntax (RFC 2141),
R. Moats, May 1997.

Uniform Resource Names (URNs) are intended to serve as persistent, location-independent, resource identifiers. This document sets forward the canonical syntax for URNs. A discussion of both existing legacy and new namespaces and requirements for URN presentation and transmission are presented. Finally, there is a discussion of URN equivalence and how to determine it.

IMAP URL Scheme (RFC 2192),
C. Newman, September 1997.

IMAP [IMAP4] is a rich protocol for accessing remote message stores. It provides an ideal mechanism for accessing public mailing list archives as well as private and shared message stores. This document defines a URL scheme for referencing objects on an IMAP server.

NFS URL Scheme (RFC 2224),
B. Callaghan, October 1997.

A new URL scheme, 'nfs' is defined. It is used to refer to files and directories on NFS servers using the general URL syntax defined in RFC 1738, "Uniform Resource Locators (URL)".

The LDAP URL Format (RFC 2255),
LDAP-WG, T. Howes, M. Smith, December 1997, Obsoletes RFC 1959.

LDAP is the Lightweight Directory Access Protocol, defined in [1], [2] and [3]. This document describes a format for an LDAP Uniform Resource Locator. The format describes an LDAP search operation to perform to retrieve information from an LDAP directory. This document replaces RFC 1959. It updates the LDAP URL format for version 3 of LDAP and clarifies how LDAP URLs are resolved. This document also defines an extension mechanism for LDAP URLs, so that future documents can extend their functionality, for example, to provide access to new LDAPv3 extensions as they are defined.

The mailto URL scheme (RFC 2368),
P. Hoffman, L. Masinter, J. Zawinski, July 1998.

This document defines the format of Uniform Resource Locators (URL) for designating electronic mail addresses. It is one of a suite of documents which replace RFC 1738, 'Uniform Resource Locators', and RFC 1808, 'Relative Uniform Resource Locators'. The syntax of 'mailto' URLs from RFC 1738 is extended to allow creation of more RFC 822 messages by allowing the URL to express additional header and body fields.

The Use of URLs as Meta-Syntax for Core Mail List Commands and their Transport through Message Header Fields (RFC 2369),
G. Neufeld, J. Baer, July 1998.

This is a proposal for additional header fields to be added to email messages sent by email distribution lists. The content of each new field is typically a URL - usually mailto [RFC2368] - which locates the relevant information or performs the command directly. MTAs generating the header fields SHOULD usually include a mailto based command, in addition to any other protocols used, in order to support users who do not have access to non-mail-based protocols.

POP URL Scheme (RFC 2384),
R. Gellens, August 1998.

This memo defines a URL scheme for referencing a POP mailbox.

Content-ID and Message-ID Uniform Resource Locators (RFC 2392),
E. Levinson, August 1998.

The Uniform Resource Locator (URL) schemes, "cid:" and "mid:" allow references to messages and the body parts of messages. For example, within a single multipart message, one HTML body part might include embedded references to other parts of the same message.

Uniform Resource Identifiers (URI): Generic Syntax (RFC 2396),
T. Berners-Lee, R. Fielding, L. Masinter, August 1998. Obsoleted by RFC 3986.
XML edition of RFC 2396.
HTML edition of RFC 2396.

A Uniform Resource Identifier (URI) is a compact string of characters for identifying an abstract or physical resource. This document defines the generic syntax of URI, including both absolute and relative forms, and guidelines for their use; it revises and replaces the generic definitions in RFC 1738 and RFC 1808.

This document defines a grammar that is a superset of all valid URI, such that an implementation can parse the common components of a URI reference without knowing the scheme-specific requirements of every possible identifier type. This document does not define a generative grammar for URI; that task will be performed by the individual specifications of each URI scheme.

The "data" URL scheme (RFC 2397),
L. Masinter, August 1998.

A new URL scheme, "data", is defined. It allows inclusion of small data items as "immediate" data, as if it had been included externally.

URI Resolution Services Necessary for URN Resolution (RFC 2483),
M. Mealling, R. Daniel, Jr., January 1999.

Retrieving the resource identified by a Uniform Resource Identifier (URI) [1] is only one of the operations that can be performed on a URI. One might also ask for and get a list of other identifiers that are aliases for the original URI or a bibliographic description of the resource the URI denotes, for example. This applies to both Uniform Resource Names (URNs) and Uniform Resource Locators (URLs). Uniform Resource Characteristics (URCs) are discussed in this document but only as descriptions of resources rather than identifiers.

Registration Procedures for URL Scheme Names (RFC 2717),
R. Petke, I. King, November 1999.
XML edition of RFC 2717.
HTML edition of RFC 2717.

This document defines the process by which new URL scheme names are registered.

Guidelines for new URL Schemes (RFC 2718),
L. Masinter, H. Alvestrand, D. Zigmond, R. Petke, November 1999.
XML edition of RFC 2718.
HTML edition of RFC 2718.

A Uniform Resource Locator (URL) is a compact string representation of the location for a resource that is available via the Internet. This document provides guidelines for the definition of new URL schemes.

Preferred Format for Literal IPv6 Addresses in URL's (RFC 2732),
R. Hinden, B. Carpenter, L. Masinter, December 1999. Obsoleted by RFC 3986.

This document defines the format for literal IPv6 Addresses in URL's for implementation in World Wide Web browsers. This format has been implemented in the IPv6 versions of several widely deployed browsers including Microsoft Internet Explorer, Mozilla, and Lynx. It is also intended to be used in the IPv6 version of the service location protocol.

This document includes an update to the generic syntax for Uniform Resource Identifiers defined in RFC 2396 [URL]. It defines a syntax for IPv6 addresses and allows the use of "[" and "]" within a URI explicitly for this reserved purpose.

Uniform Resource Identifier (URI): Generic Syntax (STD 66, RFC 3986),
T. Berners-Lee, R. Fielding, L. Masinter, January 2005.
XML edition of RFC 3986.
HTML edition of RFC 3986.
Roy Fielding's URI parsing test cases.

A Uniform Resource Identifier (URI) is a compact sequence of characters that identifies an abstract or physical resource. This specification defines the generic URI syntax and a process for resolving URI references that might be in relative form, along with guidelines and security considerations for the use of URIs on the Internet. The URI syntax defines a grammar that is a superset of all valid URIs, allowing an implementation to parse the common components of a URI reference without knowing the scheme-specific requirements of every possible identifier. This specification does not define a generative grammar for URIs; that task is performed by the individual specifications of each URI scheme.

Internationalized Resource Identifiers (IRIs) (RFC 3987),
M. Dürst and M. Suignard, January 2005.

This document defines a new protocol element, the Internationalized Resource Identifier (IRI), as a complement to the Uniform Resource Identifier (URI). An IRI is a sequence of characters from the Universal Character Set (Unicode/ISO 10646). A mapping from IRIs to URIs is defined, which means that IRIs can be used instead of URIs, where appropriate, to identify resources.

The approach of defining a new protocol element was chosen instead of extending or changing the definition of URIs. This was done in order to allow a clear distinction and to avoid incompatibilities with existing software. Guidelines are provided for the use and deployment of IRIs in various protocols, formats, and software components that currently deal with URIs.