URI Design and Ownership
RFC 7320

• Status
• IESG evaluation record
• IESG writeups
• Email expansions
• History

• Versions
• 00
• 01
• 02
• 03
• 04
• 05

Internet Engineering Task Force (IETF)                     M. Nottingham
Request for Comments: 7320
BCP: 190                                                       July 2014
Updates: 3986
Category: Best Current Practice
ISSN: 2070-1721

                        URI Design and Ownership

Abstract

   Section 1.1.1 of RFC 3986 defines URI syntax as "a federated and
   extensible naming system wherein each scheme's specification may
   further restrict the syntax and semantics of identifiers using that
   scheme."  In other words, the structure of a URI is defined by its
   scheme.  While it is common for schemes to further delegate their
   substructure to the URI's owner, publishing independent standards
   that mandate particular forms of URI substructure is inappropriate,
   because that essentially usurps ownership.  This document further
   describes this problematic practice and provides some acceptable
   alternatives for use in standards.

Status of This Memo

   This memo documents an Internet Best Current Practice.

   This document is a product of the Internet Engineering Task Force
   (IETF).  It represents the consensus of the IETF community.  It has
   received public review and has been approved for publication by the
   Internet Engineering Steering Group (IESG).  Further information on
   BCPs is available in Section 2 of RFC 5741.

   Information about the current status of this document, any errata,
   and how to provide feedback on it may be obtained at
   http://www.rfc-editor.org/info/rfc7320.

Nottingham                Best Current Practice                 [Page 1]
RFC 7320                  URI Design Ownership                 July 2014

Copyright Notice

   Copyright (c) 2014 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
     1.1.  Intended Audience . . . . . . . . . . . . . . . . . . . .   4
     1.2.  Notational Conventions  . . . . . . . . . . . . . . . . .   4
   2.  Best Current Practices for Standardizing Structured URIs  . .   4
     2.1.  URI Schemes . . . . . . . . . . . . . . . . . . . . . . .   5
     2.2.  URI Authorities . . . . . . . . . . . . . . . . . . . . .   5
     2.3.  URI Paths . . . . . . . . . . . . . . . . . . . . . . . .   5
     2.4.  URI Queries . . . . . . . . . . . . . . . . . . . . . . .   6
     2.5.  URI Fragment Identifiers  . . . . . . . . . . . . . . . .   6
   3.  Alternatives to Specifying Structure in URIs  . . . . . . . .   7
   4.  Security Considerations . . . . . . . . . . . . . . . . . . .   7
   5.  References  . . . . . . . . . . . . . . . . . . . . . . . . .   8
     5.1.  Normative References  . . . . . . . . . . . . . . . . . .   8
     5.2.  Informative References  . . . . . . . . . . . . . . . . .   8
   Appendix A.  Acknowledgments  . . . . . . . . . . . . . . . . . .   9

1.  Introduction

   URIs [RFC3986] very often include structured application data.  This
   might include artifacts from filesystems (often occurring in the path
   component) and user information (often in the query component).  In
   some cases, there can even be application-specific data in the
   authority component (e.g., some applications are spread across
   several hostnames to enable a form of partitioning or dispatch).

   Furthermore, constraints upon the structure of URIs can be imposed by
   an implementation; for example, many Web servers use the filename
   extension of the last path segment to determine the media type of the
   response.  Likewise, prepackaged applications often have highly
   structured URIs that can only be changed in limited ways (often, just
   the hostname and port on which they are deployed).

Nottingham                Best Current Practice                 [Page 2]
RFC 7320                  URI Design Ownership                 July 2014

   Because the owner of the URI (as defined in [webarch]
   Section 2.2.2.1) is choosing to use the server or the application,
   this can be seen as reasonable delegation of authority.  However,
   when such conventions are mandated by a party other than the owner,
   it can have several potentially detrimental effects:

   o  Collisions - As more ad hoc conventions for URI structure become
      standardized, it becomes more likely that there will be collisions
      between them (especially considering that servers, applications,