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Versions: 00 01 02 03 04 05 06 07 08 09 10 11 RFC 4287

Network Working Group                                 M. Nottingham, Ed.
Internet-Draft                                              July 8, 2004
Expires: January 6, 2005


                      The Atom Syndication Format
                      draft-ietf-atompub-format-00

Status of this Memo

   By submitting this Internet-Draft, I certify that any applicable
   patent or other IPR claims of which I am aware have been disclosed,
   and any of which I become aware will be disclosed, in accordance with
   RFC 3668.

   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 January 6, 2005.

Copyright Notice

   Copyright (C) The Internet Society (2004).  All Rights Reserved.

Abstract

   This specification describes Atom, an XML-based Web content and
   metadata syndication format.











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Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  4
     1.1   Editorial Notes  . . . . . . . . . . . . . . . . . . . . .  4
     1.2   Example  . . . . . . . . . . . . . . . . . . . . . . . . .  5
     1.3   Conformance  . . . . . . . . . . . . . . . . . . . . . . .  5
     1.4   Notational Conventions . . . . . . . . . . . . . . . . . .  5
   2.  Atom Documents . . . . . . . . . . . . . . . . . . . . . . . .  6
   3.  Common Atom Constructs . . . . . . . . . . . . . . . . . . . .  7
     3.1   Content Constructs . . . . . . . . . . . . . . . . . . . .  7
       3.1.1   "type" Attribute . . . . . . . . . . . . . . . . . . .  7
       3.1.2   "mode" Attribute . . . . . . . . . . . . . . . . . . .  7
     3.2   Person Constructs  . . . . . . . . . . . . . . . . . . . .  7
       3.2.1   "atom:name" Element  . . . . . . . . . . . . . . . . .  7
       3.2.2   "atom:url" Element . . . . . . . . . . . . . . . . . .  8
       3.2.3   "atom:email" Element . . . . . . . . . . . . . . . . .  8
     3.3   Date Constructs  . . . . . . . . . . . . . . . . . . . . .  8
     3.4   Link Constructs  . . . . . . . . . . . . . . . . . . . . .  8
       3.4.1   "rel" Attribute  . . . . . . . . . . . . . . . . . . .  8
       3.4.2   "type" Attribute . . . . . . . . . . . . . . . . . . .  8
       3.4.3   "href" Attribute . . . . . . . . . . . . . . . . . . .  9
       3.4.4   "hreflang" Attribute . . . . . . . . . . . . . . . . .  9
       3.4.5   "title" Attribute  . . . . . . . . . . . . . . . . . .  9
   4.  The "atom:feed" Element  . . . . . . . . . . . . . . . . . . .  9
     4.1   "version" Attribute  . . . . . . . . . . . . . . . . . . .  9
     4.2   "xml:lang" Attribute . . . . . . . . . . . . . . . . . . . 10
     4.3   "atom:title" Element . . . . . . . . . . . . . . . . . . . 10
     4.4   "atom:link" Element  . . . . . . . . . . . . . . . . . . . 10
     4.5   "atom:author" Element  . . . . . . . . . . . . . . . . . . 10
     4.6   "atom:contributor" Element . . . . . . . . . . . . . . . . 10
     4.7   "atom:tagline" Element . . . . . . . . . . . . . . . . . . 10
     4.8   "atom:id" Element  . . . . . . . . . . . . . . . . . . . . 11
     4.9   "atom:generator" Element . . . . . . . . . . . . . . . . . 11
     4.10  "atom:copyright" Element . . . . . . . . . . . . . . . . . 11
     4.11  "atom:info" Element  . . . . . . . . . . . . . . . . . . . 12
     4.12  "atom:modified" Element  . . . . . . . . . . . . . . . . . 12
     4.13  "atom:entry" Element . . . . . . . . . . . . . . . . . . . 12
       4.13.1  "atom:title" Element . . . . . . . . . . . . . . . . . 13
       4.13.2  "atom:link" Element  . . . . . . . . . . . . . . . . . 13
       4.13.3  "atom:author" Element  . . . . . . . . . . . . . . . . 13
       4.13.4  "atom:contributor" Element . . . . . . . . . . . . . . 13
       4.13.5  "atom:id" Element  . . . . . . . . . . . . . . . . . . 13
       4.13.6  "atom:modified" Element  . . . . . . . . . . . . . . . 14
       4.13.7  "atom:issued" Element  . . . . . . . . . . . . . . . . 14
       4.13.8  "atom:created" Element . . . . . . . . . . . . . . . . 14
       4.13.9  "atom:summary" Element . . . . . . . . . . . . . . . . 14
       4.13.10   "atom:content" Element . . . . . . . . . . . . . . . 14
       4.13.11   "atom:copyright" Element . . . . . . . . . . . . . . 15



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   5.  Managing Feed State  . . . . . . . . . . . . . . . . . . . . . 15
   6.  Embedding Atom in Other Formats  . . . . . . . . . . . . . . . 15
   7.  Extending Atom . . . . . . . . . . . . . . . . . . . . . . . . 15
   8.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 15
   9.  Security Considerations  . . . . . . . . . . . . . . . . . . . 16
   10.   Normative References . . . . . . . . . . . . . . . . . . . . 16
       Author's Address . . . . . . . . . . . . . . . . . . . . . . . 17
   A.  Contributors . . . . . . . . . . . . . . . . . . . . . . . . . 17
   B.  Revision History . . . . . . . . . . . . . . . . . . . . . . . 17
       Intellectual Property and Copyright Statements . . . . . . . . 19









































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1.  Introduction

   Atom is an XML-based file format intended to allow lists of related
   information, known as "feeds", to be synchronised between publishers
   and consumers.  Feeds are composed of a number of items, known as
   "entries", each with an extensible set of attached metadata.  For
   example, each entry has a title.

   The primary use case that Atom addresses is the syndication of Web
   content such as Weblogs and news headlines, to Web sites as well as
   directly to consumers.  However, nothing precludes it from being used
   for other purposes and kinds of content.

   Details of comunication protocols between software agents using Atom
   can be found in the Atom Protocol specification [Atom-protocol].

   [[ more motivation / design principles ]]

1.1  Editorial Notes

   The Atom format is a work-in-progress, and this draft is both
   incomplete and likely to change rapidly.  As a result, THE FORMAT
   DESCRIBED BY THIS DRAFT SHOULD NOT BE DEPLOYED, either in production
   systems or in any non-experimental fashion on the Internet.

   Discussion of this draft happens in two fora;

      The mailing list [1]
      The Atom Wiki Web site [2]

   Active development takes place on the mailing list, while the Wiki is
   used for issue tracking and new proposals.

   This document is an early draft and known to be incomplete.  Topics
   marked [[like this]] indicate where additional text is likely to be
   added.















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1.2  Example

   A minimal, single-entry Atom feed serialized as XML 1.0:

   <?xml version="1.0" encoding="utf-8"?>
   <feed version="draft-ietf-atompub-format-00.txt: do not deploy"
    xmlns="http://purl.org/atom/ns#draft-ietf-atompub-format-00">
     <title>Example</title>
     <link rel="alternate" type="text/html"
      href="http://example.org/"/>
     <modified>2003-12-13T18:30:02Z</modified>
     <author>
       <name>John Doe</name>
     </author>
     <entry>
       <title>Atom 0.3 snapshot</title>
       <link rel="alternate" type="text/html"
        href="http://example.org/2003/12/13/atom03"/>
       <id>tag:example.org,2003:3.2397</id>
       <issued>2003-12-13T08:29:29-04:00</issued>
       <modified>2003-12-13T18:30:02Z</modified>
     </entry>
   </feed>


1.3  Conformance

   [[ talk about atom documents and atom consumers, and how requirements
   are placed on them ]]

1.4  Notational Conventions

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in [RFC2119].

   This specification uses XML Namespaces [W3C.REC-xml-names-19990114]
   to uniquely identify XML elements and attribute names.  It uses the
   following namespace prefixes for the indicated namespace URIs;

   "atom":  http://purl.org/atom/ns#draft-ietf-atompub-format-00

   Note that the choice of any namespace prefix is arbitrary and not
   semantically significant.

   Atom is specified using the XML Infoset
   [W3C.REC-xml-infoset-20011024].  However, this specification uses a
   shorthand for common terms; the phrase "Information Item" is not used



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   when naming XML constructs.

   Therefore, when this specification uses the term "element," it is
   refering to an Element Information Item in Infoset terms.  Likewise,
   when it uses the term "attribute," it is refering to an Attribute
   Information Item.

2.  Atom Documents

   An Atom document is an XML document whose document element is the
   atom:feed element, as described below.

   Atom documents are specified in terms of the XML Information Set,
   serialised as XML 1.0 and identified with the "application/atom+xml"
   media type.

   Atom documents MAY have a Document Type Declaration.

   [[Entities]]

   Atom documents SHOULD NOT contain Processing Instructions, unless
   they are a commonly used convention outside the scope of Atom (e.g.,
   the PI for XSLT processing).

   Atom documents MAY contain Comments.

   All elements and attributes in an Atom document MUST be
   namespace-qualified.  Note that this requirement does not preclude
   the use of a default namespace.

   Any element in an Atom document MAY have an xml:base attribute.  XML
   Base [W3C.REC-xmlbase-20010627] processing MUST be applied to any
   relative URI reference present in an Atom document.  This includes
   such elements and attributes as specified by Atom itself, as well as
   those specified by extensions to Atom.

   Any element in an Atom document MAY have an xml:lang attribute, whose
   content indicates the default natural language of the element's
   content.  The content of this attribute MUST be a language tag
   [RFC3066].  When determining element content's natural language, the
   first xml:lang attribute encountered in that element's ancestors MUST
   be used.

   Atom is extensible.  See the section titled 'Extending Atom' later in
   this document for a full description of how extensions can be made to
   the format.





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3.  Common Atom Constructs

   Many of Atom's elements share a common structure.  This section
   defines a few such structures and their requirements, for convenient
   reference by the appropriate element definitions.

   When an element is identified as being a construct, it inherits the
   corresponding requirements from that construct's definition in this
   section.

3.1  Content Constructs

   A Content construct is an element with arbitrary child content, whose
   properties are described by the following attributes:

3.1.1  "type" Attribute

   Content constructs MAY have a "type" attribute, whose value indicates
   the media type of the content.  When present, this attribute's value
   MUST be a registered media type [RFC2045].  If not present, its value
   MUST be considered to be "text/plain".

3.1.2  "mode" Attribute

   Content constructs MAY have a "mode" attribute, whose value indicates
   the method used to encode the content.  When present, this
   attribute's value MUST be listed below.  If not present, its value
   MUST be considered to be "xml".

   "xml":  A mode attribute with the value "xml" indicates that the
      element's content is inline xml (for example, namespace-qualified
      XHTML).
   "escaped":  A mode attribute with the value "escaped" indicates that
      the element's content is an escaped string.  Processors MUST
      unescape the element's content before considering it as content of
      the indicated media type.
   "base64":  A mode attribute with the value "base64" indicates that
      the element's content is base64-encoded [RFC2045].  Processors
      MUST decode the element's content before considering it as content
      of the the indicated media type.

3.2  Person Constructs

   A Person construct is an element with the following children:

3.2.1  "atom:name" Element

   The "atom:name" element's content conveys a human-readable name for



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   the author.  It MAY be the name of a corporation or other entity no
   individual authors can be named.  Person constructs MUST contain
   exactly one "atom:name" element, whose content MUST be a string.

3.2.2  "atom:url" Element

   The "atom:url" element's content conveys a URI associated with the
   author.  Person constructs MAY contain an atom:url element, but MUST
   NOT contain more than one.  The content of atom:url in a Person
   construct MUST be a URI [RFC2396].

   xml:base [W3C.REC-xmlbase-20010627] processing MUST be applied to the
   atom:url element's content.

3.2.3  "atom:email" Element

   The "atom:email" element's content conveys an e-mail address
   associated with the Person construct.  Person constructs MAY contain
   an atom:email element, but MUST NOT contain more than one.  Its
   content MUST be an e-mail address [RFC2822].

   Ordering of the element children of Person constructs MUST NOT be
   considered significant.

3.3  Date Constructs

   A Date construct is an element whose child content is a W3C Date-Time
   string [W3C.NOTE-datetime-19980827].

3.4  Link Constructs

   A Link construct is an element that MUST NOT have any child content,
   and has the following attributes:

3.4.1  "rel" Attribute

   The "rel" attribute indicates the type of relationship that the link
   represents.  Link constructs MUST have a rel attribute, whose value
   MUST be a string, and MUST be one of the values enumerated in the
   Atom Protocol specification [Atom-protocol].

3.4.2  "type" Attribute

   The "type" attribute indicates an advisory media type; it MAY be used
   as a hint to determine the type of the representation which should be
   returned when the URI in the href attribute is dereferenced.  Note
   that the type attribute does not override the actual media type
   returned with the representation.



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   Link constructs MUST have a type attribute, whose value MUST be a
   registered media type [RFC2045].

3.4.3  "href" Attribute

   The "href" attribute contains the link's URI.  Link constructs MUST
   have a href attribute, whose value MUST be a URI [RFC2396].

   xml:base [W3C.REC-xmlbase-20010627] processing MUST be applied to the
   href attribute's content.

3.4.4  "hreflang" Attribute

   The "hreflang" attribute's content describes the language of the
   resource pointed to by the href attribute.  When used together with
   the rel="alternate", it implies a translated version of the entry.
   Link constructs MAY have an hreflang attribute, whose value MUST be a
   language tag [RFC3066].

3.4.5  "title" Attribute

   The "title" attribute conveys human-readable information about the
   link.  Link constructs MAY have a title attribute, whose value MUST
   be a string.

4.  The "atom:feed" Element

   The "atom:feed" element is the document (i.e., top-level) element of
   the format described by this specification.  Its children are a
   (potentially partial) representation of the state of the feed.

   The atom:feed element MAY contain any namespace-qualified
   [W3C.REC-xml-names-19990114] elements as children.  Ordering of the
   element children of atom:feed element MUST NOT be considered
   significant.

   The following attributes and child elements are defined by this
   specification (note that it requires the presence of some of these
   elements):

4.1  "version" Attribute

   atom:feed elements MUST have a "version" attribute whose content
   indicates the version of the Atom specification that the construct
   conforms to.  The content of this attribute is unstructured text.

   The version identifier for this specification is
   "draft-ietf-atompub-format-00: do not deploy".



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4.2  "xml:lang" Attribute

   atom:feed elements SHOULD have an "xml:lang" attribute whose content
   indicates the default natural language of the feed.  The content of
   this attribute MUST be a language tag [RFC3066].

4.3  "atom:title" Element

   The "atom:title" element is a Content construct that conveys a
   human-readable title for the feed.  atom:feed elements MUST contain
   exactly one atom:title element.  If the feed describes a Web
   resource, its content SHOULD be the same as that resource's title.

4.4  "atom:link" Element

   The "atom:link" element is a Link construct that conveys a URI
   associated with the feed.  The nature of the relationship as well as
   the link itself is determined by the element's content.

   atom:feed elements MUST contain at least one atom:link element with a
   rel attribute value of "alternate".

   atom:feed elements MUST NOT contain more than one atom:link element
   with a rel attribute value of "alternate" that has the same type
   attribute value.

   atom:feed elements MAY contain additional atom:link elements beyond
   those described above.

4.5  "atom:author" Element

   The "atom:author" element is a Person construct that indicates the
   default author of the feed.  atom:feed elements MUST contain exactly
   one atom:author element, UNLESS all of the atom:feed element's child
   atom:entry elements contain an atom:author element.  atom:feed
   elements MUST NOT contain more than one atom:author element.

   [[explain inheritence]]

4.6  "atom:contributor" Element

   The "atom:contributor" element is a Person construct that indicates a
   person or other entity who contributes to the feed.  atom:feed
   elements MAY contain one or more atom:contributor elements.

4.7  "atom:tagline" Element

   The "atom:tagline" element is a Content construct that conveys a



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   human-readable description or tagline for the feed.  atom:feed
   elements MAY contain an atom:tagline element, but MUST NOT contain
   more than one.

4.8  "atom:id" Element

   The "atom:id" element's content conveys a permanent, globally unique
   identifier for the feed.  It MUST NOT change over time, even if the
   feed is relocated.  atom:feed elements MAY contain an atom:id
   element, but MUST NOT contain more than one.  The content of this
   element, when present, MUST be a URI.

   xml:base [W3C.REC-xmlbase-20010627] processing MUST be applied to the
   atom:id element's content.

4.9  "atom:generator" Element

   The "atom:generator" element's content indentifies the software agent
   used to generate the feed, for debugging and other purposes.
   atom:feed elements MAY contain an atom:generator element, but MUST
   NOT contain more than one.

   The content of this element, when present, MUST be a string that is a
   human-readable name for the generating agent.

   The atom:generator element MAY have a "url" attribute whose value
   MUST be a URI.  When dereferenced, that URI SHOULD produce a
   representation that is relevant to that agent.

   The atom:generator element MAY have a "version" attribute that
   indicates the version of the generating agent.  When present, its
   value MUST be a string.

4.10  "atom:copyright" Element

   The "atom:copyright" element is Content construct that conveys a
   human-readable copyright statement for the feed.  atom:feed elements
   MAY contain an atom:copyright element, but MUST NOT contain more than
   one.

   The atom:copyright element SHOULD NOT be used to convey
   machine-readable licensing information.

   The atom:copyright may be assumed to apply to all entries contained
   by the feed except those entries which contain atom:copyright
   elements.  The atom:copyright element MUST, if present, be considered
   to apply to the feed as a collection of entries.




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4.11  "atom:info" Element

   The "atom:info" element is a Content construct that conveys a
   human-readable explanation of the feed format itself.  atom:feed
   elements MAY contain an atom:info element, but MUST NOT contain more
   than one.

   The atom:info element SHOULD NOT considered meaningful by processors;
   it is a convenience to publishers in certain situations.

4.12  "atom:modified" Element

   The "atom:modified" element is a Date construct that indicates the
   time when the state of the feed was last modified, including any
   changes to entries therein.  atom:feed elements MUST contain exactly
   one atom:modified element.

   The content of an atom:modified element SHOULD have a time zone whose
   value MUST be "UTC".

4.13  "atom:entry" Element

   The "atom:entry" element represents an individual entry that is
   contained by the feed.  atom:feed elements MAY contain one or more
   atom:entry elements.

   atom:entry elements MAY have an "xml:lang" attribute whose content
   indicates the default natural language of the entry.  If the language
   of the atom:entry is different from the language of the feed then the
   atom:entry SHOULD have an "xml:lang" attribute.  The content of this
   attribute element MUST be a language tag [RFC3066] or an empty string
   (e.g., xml:lang=""), which indicates that there is no language
   information available.

   If used alone, atom:entry elements MUST have a "version" attribute
   whose content indicates the version of the Atom specification that
   the construct conforms to.

   The atom:entry element MAY contain any namespace-qualified
   [W3C.REC-xml-names-19990114] elements as children.  Ordering of the
   element children of atom:entry element MUST NOT be considered
   significant.

   The following child elements are defined by this specification (note
   that it requires the presence of some of these elements):






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4.13.1  "atom:title" Element

   The "atom:title" element is a Content construct that conveys a
   human-readable title for the entry.  atom:entry elements MUST have
   exactly one "atom:title" element.  If an entry describes a Web
   resource, its content SHOULD be the same as that resource's title.

4.13.2  "atom:link" Element

   The "atom:link" element is a Link construct that conveys a URI
   associated with the entry.  The nature of the relationship as well as
   the link itself is determined by the element's content.

   atom:entry elements MUST contain at least one atom:link element with
   a rel attribute value of "alternate".

   atom:entry elements MUST NOT contain more than one atom:link element
   with a rel attribute value of "alternate" that has the same type
   attribute value.

   atom:entry elements MAY contain additional atom:link elements beyond
   those described above.

4.13.3  "atom:author" Element

   The "atom:author" element is a Person construct that indicates the
   default author of the entry.  atom:entry elements MUST contain
   exactly one atom:author element, UNLESS the atom:feed element
   containing them contains an atom:author element itself.  atom:entry
   elements MUST NOT contain more than one atom:author element.

   [[explain inheritence]]

4.13.4  "atom:contributor" Element

   The "atom:contributor" element is a Person construct that indicates a
   person or other entity who contributes to the entry.  atom:entry
   elements MAY contain one or more atom:contributor elements.

4.13.5  "atom:id" Element

   The "atom:id" element's content conveys a permanent, globally unique
   identifier for the entry.  It MUST NOT change over time, even if
   other representations of the entry (such as a web representation
   pointed to by the entry's atom:link element) are relocated.  If the
   same entry is syndicated in two atom:feeds published by the same
   entity, the entry's atom:id MUST be the same in both feeds.




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4.13.6  "atom:modified" Element

   The "atom:modified" element is a Date construct that indicates the
   time that the entry was last modified.  atom:entry elements MUST
   contain an atom:modified element, but MUST NOT contain more than one.

   The content of an atom:modified element MUST have a time zone whose
   value SHOULD be "UTC".

4.13.7  "atom:issued" Element

   The "atom:issued" element is a Date construct that indicates the time
   that the entry was issued.  atom:entry elements MUST contain an
   atom:issued element, but MUST NOT contain more than one.

   The content of an atom:issued element MAY omit a time zone.

4.13.8  "atom:created" Element

   The "atom:created" element is a Date construct that indicates the
   time that the entry was created.  atom:entry elements MAY contain an
   atom:created element, but MUST NOT contain more than one.

   The content of an atom:created element MUST have a time zone whose
   value SHOULD be "UTC".

   If atom:created is not present, its content MUST considered to be the
   same as that of atom:modified.

4.13.9  "atom:summary" Element

   The "atom:summary" element is a Content construct that conveys a
   short summary, abstract or excerpt of the entry.  atom:entry elements
   MAY contain an atom:created element, but MUST NOT contain more than
   one.

4.13.10  "atom:content" Element

   The "atom:content" element is a Content construct that conveys the
   content of the entry.  atom:entry elements MAY contain one or more
   atom:content elements.

   If @type="multipart/alternative", @mode MUST NOT be specified, and
   content element MUST contain 1 or more content elements.  These
   content elements MUST NOT specify @type="multipart/alternative" (i.e.
   only one level of nesting is allowed).  Consumers SHOULD look at all
   alternative content elements and determine which one is most
   suitable, based on which @type and @mode the consumer supports, and



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   preferences specified by the end user (if any).  Consumers SHOULD NOT
   render more than one content alternative.

4.13.11  "atom:copyright" Element

   The "atom:copyright" element is a Content construct that conveys a
   human-readable copyright statement for the entry.  atom:entry
   elements MAY contain an atom:copyright element, but MUST NOT contain
   more than one.

   The atom:copyright element SHOULD NOT be used to convey
   machine-readable licensing information.

   If an atom:entry element does not contain an atom:copyright element,
   then the atom:copyright element of the containing atom:feed, if
   present, should be considered to apply to the atom:entry.

5.  Managing Feed State

   [[ talk about what it means to keep a view of a feed ]]

6.  Embedding Atom in Other Formats

   [[ ...  ]]

7.  Extending Atom

   [[ ...  ]]

8.  IANA Considerations

   The Atom format, when serialized as XML 1.0, can be identified with
   the following media type:

   MIME media type name: application
   MIME subtype name: atom+xml
   Mandatory parameters: None.
   Optional parameters:
      "charset": This parameter has identical semantics to the charset
         parameter of the "application/xml" media type as specified in
         RFC 3023 [RFC3023].  [RFC3023].
   Encoding considerations: Identical to those of "application/xml" as
      described in RFC 3023 [RFC3023], section 3.2.
   Security considerations: As defined in this specification.  [[update
      upon publication]]






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      In addition, as this media type uses the "+xml" convention, it
      shares the same security considerations as described in RFC 3023
      [RFC3023], section 10.
   Interoperability considerations: There are no known interoperability
      issues.
   Published specification: This specification.  [[update upon
      publication]]
   Applications which use this media type: No known applications
      currently use this media type.

   Additional information:

   Magic number(s): As specified for "application/xml" in RFC 3023
      [RFC3023], section 3.2.
   File extension: .atom
   Fragment identifiers: As specified for "application/xml" in RFC 3023
      [RFC3023], section 5.
   Base URI: As specified in RFC 3023 [RFC3023], section 6.
   Macintosh File Type code: TEXT
   Person and email address to contact for further information: Mark
      Nottingham <mnot@pobox.com>
   Intended usage: COMMON
   Author/Change controller: This specification's author(s).  [[update
      upon publication]]

9.  Security Considerations

   [[ this is required ]]

10  Normative References

   [Atom-protocol]
              Gregorio, J. and R. Sayre, "The Atom Publishing Protocol",
              work-in-progress, July 2004.

   [RFC2045]  Freed, N. and N. Borenstein, "Multipurpose Internet Mail
              Extensions (MIME) Part One: Format of Internet Message
              Bodies", RFC 2045, November 1996.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC2396]  Berners-Lee, T., Fielding, R. and L. Masinter, "Uniform
              Resource Identifiers (URI): Generic Syntax", RFC 2396,
              August 1998.

   [RFC2822]  Resnick, P., "Internet Message Format", RFC 2822, April
              2001.



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   [RFC3023]  Murata, M., St. Laurent, S. and D. Kohn, "XML Media
              Types", RFC 3023, January 2001.

   [RFC3066]  Alvestrand, H., "Tags for the Identification of
              Languages", BCP 47, RFC 3066, January 2001.

   [W3C.NOTE-datetime-19980827]
              Wolf, M. and C. Wicksteed, "Date and Time Formats", W3C
              NOTE NOTE-datetime-19980827, August 1998.

   [W3C.REC-xml-infoset-20011024]
              Cowan, J. and R. Tobin, "XML Information Set", W3C REC
              REC-xml-infoset-20011024, October 2001.

   [W3C.REC-xml-names-19990114]
              Bray, T., Hollander, D. and A. Layman, "Namespaces in
              XML", W3C REC REC-xml-names-19990114, January 1999.

   [W3C.REC-xmlbase-20010627]
              Marsh, J., "XML Base", W3C REC REC-xmlbase-20010627, June
              2001.

   [1]  <http://www.imc.org/atom-syntax/index.html>

   [2]  <http://www.intertwingly.net/wiki/pie/FrontPage>


Author's Address

   Mark Nottingham (editor)

   EMail: mnot@pobox.com
   URI:   http://www.mnot.net/

Appendix A.  Contributors

   The following people contributed to preliminary drafts of this
   document: Tim Bray, Mark Pilgrim, and Sam Ruby.  The content and
   concepts within are a product of the Atom community and the Atom
   Publishing Format and Protocol Working Group.

Appendix B.  Revision History

   [[ this section should be removed before final publication.  ]]







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   2004-07-06 (-00):  Initial IETF Internet-Draft submission.
      Added optional version attribute to entry
      (PaceEntryElementNeedsVersionAttribute).
      Added hreflang attribute (PaceHrefLang).
      Clarified inheritence of copyright element (PaceItemCopyright).
      Added xml:lang to entries (PaceItemLang).
      Tweaked Infoset-related language (PaceNoInfoSet).
      Clarified lack of structure in version attribute
      (PaceVersionAsText).
      Changed approach to XML Base (PaceXmlBaseEverywhere).
      Added XML Base processing to atom:id (PaceXmlBaseId).
      Various editorial cleanup and adjustments for IETF publication.







































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