Defining Well-Known Uniform Resource Identifiers (URIs)
RFC 5785
Document | Type |
RFC - Proposed Standard
(April 2010; Errata)
Obsoleted by RFC 8615
Was draft-nottingham-site-meta (individual in app area)
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|
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Authors | Eran Hammer-Lahav , Mark Nottingham | ||
Last updated | 2020-01-21 | ||
Stream | IETF | ||
Formats | plain text html pdf htmlized with errata bibtex | ||
Reviews | |||
Stream | WG state | (None) | |
Document shepherd | No shepherd assigned | ||
IESG | IESG state | RFC 5785 (Proposed Standard) | |
Consensus Boilerplate | Unknown | ||
Telechat date | |||
Responsible AD | Lisa Dusseault | ||
Send notices to | (None) |
Internet Engineering Task Force (IETF) M. Nottingham Request for Comments: 5785 E. Hammer-Lahav Updates: 2616, 2818 April 2010 Category: Standards Track ISSN: 2070-1721 Defining Well-Known Uniform Resource Identifiers (URIs) Abstract This memo defines a path prefix for "well-known locations", "/.well-known/", in selected Uniform Resource Identifier (URI) schemes. Status of This Memo This is an Internet Standards Track document. 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 Internet Standards 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/rfc5785. Copyright Notice Copyright (c) 2010 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. Nottingham & Hammer-Lahav Standards Track [Page 1] RFC 5785 Defining Well-Known URIs April 2010 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 2 1.1. Appropriate Use of Well-Known URIs . . . . . . . . . . . . 3 2. Notational Conventions . . . . . . . . . . . . . . . . . . . . 3 3. Well-Known URIs . . . . . . . . . . . . . . . . . . . . . . . . 3 4. Security Considerations . . . . . . . . . . . . . . . . . . . . 4 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 4 5.1. The Well-Known URI Registry . . . . . . . . . . . . . . . . 4 5.1.1. Registration Template . . . . . . . . . . . . . . . . . 5 6. References . . . . . . . . . . . . . . . . . . . . . . . . . . 5 6.1. Normative References . . . . . . . . . . . . . . . . . . . 5 6.2. Informative References . . . . . . . . . . . . . . . . . . 5 Appendix A. Acknowledgements . . . . . . . . . . . . . . . . . . . 7 Appendix B. Frequently Asked Questions . . . . . . . . . . . . . . 7 1. Introduction It is increasingly common for Web-based protocols to require the discovery of policy or other information about a host ("site-wide metadata") before making a request. For example, the Robots Exclusion Protocol <http://www.robotstxt.org/> specifies a way for automated processes to obtain permission to access resources; likewise, the Platform for Privacy Preferences [W3C.REC-P3P-20020416] tells user-agents how to discover privacy policy beforehand. While there are several ways to access per-resource metadata (e.g., HTTP headers, WebDAV's PROPFIND [RFC4918]), the perceived overhead (either in terms of client-perceived latency and/or deployment difficulties) associated with them often precludes their use in these scenarios. When this happens, it is common to designate a "well-known location" for such data, so that it can be easily located. However, this approach has the drawback of risking collisions, both with other such designated "well-known locations" and with pre-existing resources. To address this, this memo defines a path prefix in HTTP(S) URIs for these "well-known locations", "/.well-known/". Future specifications that need to define a resource for such site-wide metadata can register their use to avoid collisions and minimise impingement upon sites' URI space. Nottingham & Hammer-Lahav Standards Track [Page 2] RFC 5785 Defining Well-Known URIs April 2010 1.1. Appropriate Use of Well-Known URIs There are a number of possible ways that applications could use Well- known URIs. However, in keeping with the Architecture of the World- Wide Web [W3C.REC-webarch-20041215], well-known URIs are not intended for general information retrieval or establishment of large URI namespaces on the Web. Rather, they are designed to facilitate discovery of information on a site when it isn't practical to use other mechanisms; for example, when discovering policy that needs to be evaluated before a resource is accessed, or when using multipleShow full document text