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 November 29, 2008.
This specification defines a link relation that enables an Atom document to point to a venue for multi-party discussion of the document or its primary topic.
2. Notational Conventions
3. The 'discuss' Link Relation
5. Security Considerations
6. IANA Considerations
7.1. Normative References
7.2. Informative References
§ Author's Address
§ Intellectual Property and Copyright Statements
Atom [ATOM] (Nottingham, M. and R. Sayre, “The Atom Syndication Format,” December 2005.) is an XML-based document format that describes lists of related information known as "feeds". Feeds are composed of a number of items, known as "entries", each with an extensible set of attached metadata. Such metadata can include links to other resources, which are primarily defined by Uniform Resource Indentifiers [URI] (Berners-Lee, T., Fielding, R., and L. Masinter, “Uniform Resource Identifier (URI): Generic Syntax,” January 2005.) or Internationalized Resource Indentifiers [IRI] (Duerst, M. and M. Suignard, “Internationalized Resource Identifiers (IRIs),” January 2005.). A link can be secondarily defined as partaking in a specific kind of relationship to the document. This specification defines a new link relation, "discuss", which can be used to point to Internet resources where a person can actively engage in a multi-party discussion or conversation about the document itself or the primary topic covered by the document.
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 [TERMS] (Bradner, S., “Key words for use in RFCs to Indicate Requirement Levels,” March 1997.).
This specification allows the use of Internationalized Resource Identifiers [IRI] (Duerst, M. and M. Suignard, “Internationalized Resource Identifiers (IRIs),” January 2005.). Every Uniform Resource Identifier [URI] (Berners-Lee, T., Fielding, R., and L. Masinter, “Uniform Resource Identifier (URI): Generic Syntax,” January 2005.) is also an IRI, so a URI may be used wherever an IRI is named. When an IRI that is not also a URI is given for dereferencing, it MUST be mapped to a URI using the steps in Section 3.1 of [URI] (Berners-Lee, T., Fielding, R., and L. Masinter, “Uniform Resource Identifier (URI): Generic Syntax,” January 2005.). When an IRI is serving as an identifier, it MUST NOT be so mapped.
An Atom link element with a rel attribute value of "discuss" is used to reference an Internet resource where multi-party discussion of the feed, entry, or source can occur. In the terminology of this specification, such a resource is called a "venue". Such venues might include, but are not limited to, the following:
The use of the "discuss" relation enables a person who receives an Atom feed or entry to discover a venue where the person can engage in a conversation about the feed or entry with interested others. This use case is not currently addressed by any existing Atom link relation, which to date address use cases such as reading background material (the "related" relation) or following other people's comments (the "comments" relation) rather than actively engaging in a conversation or discussion about the feed or entry.
It is expected that a link relation of type "discuss" would be presented to a human user in such a way that the user would understand that following the link would result in joining an active discussion venue rather than accessing a static resource.
If the rel attribute has a value of "discuss" but the type attribute of the atom:link is omitted, no type value shall be assumed.
Although Atom feed, entry, and source elements MAY each contain any number of atom:link elements using the "discuss" link relation, this specification assigns no significance to the presence or order of such links. Multiple discuss links appearing within an atom:entry may reference alternative representations of the same venue or may reference entirely distinct venues containing distinct conversations. Processors MUST NOT assume that multiple discuss links make reference to different representations of the same venue and MUST process each discuss link independently of any others.
The following example shows an Atom entry that contains numerous links related to the ejabberd XMPP server project, including links to an XMPP chatroom, an email discussion list, a web forum, and two web pages with background information.
<entry xmlns='http://www.w3.org/2005/Atom'> <source> <title>Example.org Admin Feed</title> <link href='http://example.org/'/> <link rel='self' type='application/atom+xml' href='http://example.org/atom.xml'/> <id>tag:example.org,2008:home</id> <updated>2008-05-27T17:30:03Z</updated> <author> <name>Example.org Admin Team</name> </author> </source> <title>Service Upgrade</title> <summary>We have upgraded to ejabberd 2.0</summary> <link rel='alternate' type='text/html' href='http://example.org/2008/05/27/atom03'/> <link rel='discuss' href='xmpp:email@example.com?join' label='Real-time chatroom about ejabberd'/> <link rel='discuss' href='mailto:firstname.lastname@example.org' label='Email discussion list about ejabberd'/> <link rel='discuss' href='http://www.ejabberd.im/forum' label='Web forum about ejabberd'/> <link rel='related' href='http://ejabberd.im/' label='Project homepage for ejabberd'/> <link rel='related' href='http://en.wikipedia.org/wiki/Ejabberd' label='Wikipedia page about ejabberd'/> <id>tag:example.org,2008:entry-32397</id> <published>2008-05-27T17:30:03Z</published> <updated>2008-05-27T17:30:03Z</updated> </entry>
Notice that the entry contains three links of type "relation" (which can be differentiated via the URI scheme, i.e., "xmpp" vs. "mailto" vs. http") and three links to HTTP resources (which can be differentiated via the relation type, i.e., "discuss" vs. "related").
This document introduces few additional security considerations beyond those associated with the use and resolution of URIs/IRIs in general.
However, depending on the technology used and the local service policy at a particular installation, a venue for multi-party discussion may expose personally-identifying information about the participants (e.g., IP addresses), may be public in the sense that anyone can join the venue, and may archive the conversations that occur in the venue either privately or publicly (e.g., on the World Wide Web). An Atom user agent or the appropriate helper application should warn a human user about the possibility of information exposure and public archiving.
This specification defines one new Atom link relation type, which shall be registered in the IANA Registry of Atom Link Relations, as defined by [ATOM] (Nottingham, M. and R. Sayre, “The Atom Syndication Format,” December 2005.).
- Attribute value:
- (see Section 3 (The 'discuss' Link Relation))
- Expected display characteristics:
- (see Section 3 (The 'discuss' Link Relation))
- Security considerations:
- (see Section 5 (Security Considerations))
|[ATOM]||Nottingham, M. and R. Sayre, “The Atom Syndication Format,” RFC 4287, December 2005 (TXT).|
|[IRI]||Duerst, M. and M. Suignard, “Internationalized Resource Identifiers (IRIs),” RFC 3987, January 2005 (TXT).|
|[TERMS]||Bradner, S., “Key words for use in RFCs to Indicate Requirement Levels,” BCP 14, RFC 2119, March 1997 (TXT, HTML, XML).|
|[URI]||Berners-Lee, T., Fielding, R., and L. Masinter, “Uniform Resource Identifier (URI): Generic Syntax,” STD 66, RFC 3986, January 2005 (TXT).|
|[HTTP]||Fielding, R., Gettys, J., Mogul, J., Frystyk, H., Masinter, L., Leach, P., and T. Berners-Lee, “Hypertext Transfer Protocol -- HTTP/1.1,” RFC 2616, June 1999 (TXT, PS, PDF, HTML, XML).|
|[IRC]||Oikarinen, J. and D. Reed, “Internet Relay Chat Protocol,” RFC 1459, May 1993 (TXT).|
|[MSRP]||Campbell, B., Mahy, R., and C. Jennings, “The Message Session Relay Protocol (MSRP),” RFC 4975, September 2007 (TXT).|
|[MUC]||Saint-Andre, P., “Multi-User Chat,” XSF XEP 0045, April 2007.|
|[NNTP]||Kantor, B. and P. Lapsley, “Network News Transfer Protocol,” RFC 977, February 1986 (TXT).|
|[SIP]||Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston, A., Peterson, J., Sparks, R., Handley, M., and E. Schooler, “SIP: Session Initiation Protocol,” RFC 3261, June 2002 (TXT).|
|[XMPP]||Saint-Andre, P., “Extensible Messaging and Presence Protocol (XMPP): Core,” RFC 3920, October 2004 (TXT).|
|XMPP Standards Foundation|
|P.O. Box 1641|
|Denver, CO 80201|
Copyright © 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.
The IETF takes no position regarding the validity or scope of any Intellectual Property Rights or other rights that might be claimed to pertain to the implementation or use of the technology described in this document or the extent to which any license under such rights might or might not be available; nor does it represent that it has made any independent effort to identify any such rights. Information on the procedures with respect to rights in RFC documents can be found in BCP 78 and BCP 79.
Copies of IPR disclosures made to the IETF Secretariat and any assurances of licenses to be made available, or the result of an attempt made to obtain a general license or permission for the use of such proprietary rights by implementers or users of this specification can be obtained from the IETF on-line IPR repository at http://www.ietf.org/ipr.
The IETF invites any interested party to bring to its attention any copyrights, patents or patent applications, or other proprietary rights that may cover technology that may be required to implement this standard. Please address the information to the IETF at email@example.com.