Network Working Group L. Hunt Internet-Draft Opera Software, ASA. Expires: July 29, 2008 January 26, 2008 The "about" URI Scheme draft-lachy-about-uri-00 Status of this Memo By submitting this Internet-Draft, each author represents that any applicable patent or other IPR claims of which he or she is aware have been or will be disclosed, and any of which he or she becomes aware will be disclosed, in accordance with Section 6 of BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet- Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt. The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. This Internet-Draft will expire on July 29, 2008. Abstract This document describes the "about" Uniform Resource Identifier (URI) scheme. About URIs are designed to be an internal, application-level identifier. Unlike many other URI schemes, the resolution of, and resources represented by, about URIs is left entirely to each individual application. Table of Contents 1. Introduction 2. Syntax 3. Resolving About URIs 3.1. about:blank 3.2. Examples 4. Security Considerations Author's Address Intellectual Property and Copyright Statements 1. Introduction An about URI is designed to be used internally by applications for almost any desired purpose. Such URIs have commonly been used by web browsers for proving access to built-in functionality, such as application preferences and settings, information about the application, or "easter eggs". 2. Syntax abouturl = "about:" segment Where "segment" is imported from [RFC2396] 3. Resolving About URIs In general, applications are free to resolve any about URI to any resource, either internal or external, or redirect to an alternative URI, with about:blank (Section 3.1) being the only exception. As about URIs are designed to be internal to each application, there is no expectation of any URI, except about:blank, returning the same resource among different applications. However, it is worth noting that some conventions have arisen for providing particular functionality via common about URIs. The about:blank URI is the only about URI reserved by this specification. 3.1. about:blank Applications resolving this URI must return an empty resource, with the media type "text/html" and the character encoding "UTF-8". 3.2. Examples The following examples illustrate some known URIs supported by existing applications. about:config Commonly provides access to application preferences and settings about:cache Commonly provides access to information about resources stored in the browsers cache. about:plugins Commonly provides access to information about installed plugins about:mozilla An easter egg supported by Mozilla showing a passage from the fictional Book of Mozilla about:internets An easter egg supported by Google Chrome depicting the internet as a series of tubes. Applications are also permitted redirect such URIs. For example, Opera redirects all about: URIs, with the exception of about:blank, to the equivalent URI using their internal opera: scheme. e.g. about: config redirects to opera:config. This is not an exhaustive list. Many more are supported by numerous applications. For more examples, consult Wikipedia's entry on the "about: URI Scheme". 4. Security Considerations [insert information about Origin] Author's Address Lachlan Hunt Opera Software, ASA. Email: lachlan.hunt@lachy.id.au URI: http://lachy.id.au/ Full Copyright Statement Copyright (C) The IETF Trust (2008). This document is subject to the rights, licenses and restrictions contained in BCP 78, and except as set forth therein, the authors retain all their rights. This document and the information contained herein are provided on an "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY, THE IETF TRUST AND THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. 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