SIMPLE H. Schulzrinne Internet-Draft Columbia U. Expires: December 28, 2005 June 26, 2005 Timed Presence Extensions to the Presence Information Data Format (PIDF) to Indicate Status Information for Past and Future Time Intervals draft-ietf-simple-future-04 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 December 28, 2005. Copyright Notice Copyright (C) The Internet Society (2005). Abstract The Presence Information Data Format (PIDF) defines a basic XML format for presenting presence information for a presentity. This document extends PIDF, adding a timed status extension ( element) that allows a presentity to declare its status for a time interval fully in the future or the past. Schulzrinne Expires December 28, 2005 [Page 1] Internet-Draft Timed Presence June 2005 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Terminology and Conventions . . . . . . . . . . . . . . . . . 4 3. Timed-Status Element . . . . . . . . . . . . . . . . . . . . . 5 4. Example . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 5. The XML Schema Definition . . . . . . . . . . . . . . . . . . 7 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8 6.1 URN Sub-Namespace Registration for 'urn:ietf:params:xml:ns:pidf:timed-status' . . . . . . . . 8 6.2 Schema Registration for Schema urn:ietf:params:xml:ns:pidf:timed-status' . . . . . . . . 8 7. Security Considerations . . . . . . . . . . . . . . . . . . . 10 8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 11 8.1 Normative References . . . . . . . . . . . . . . . . . . . 11 8.2 Informative References . . . . . . . . . . . . . . . . . . 11 Author's Address . . . . . . . . . . . . . . . . . . . . . . . 11 A. Contributors . . . . . . . . . . . . . . . . . . . . . . . . . 12 B. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 13 Intellectual Property and Copyright Statements . . . . . . . . 14 Schulzrinne Expires December 28, 2005 [Page 2] Internet-Draft Timed Presence June 2005 1. Introduction Traditionally, presence information, e.g., represented as PIDF [3] and RPID [6], describes the current state of the presentity. However, a watcher can better plan communications if it knows about the presentity's future plans. For example, if a watcher knows that the presentity is about to travel, it might place a phone call earlier. RPID already allows a presentity to indicate the period when a particular aspect of its presence is valid. However, the element in the PIDF does not have this facility, so that it is not possible to indicate that a presentity will be OPEN or CLOSED in the future, for example. It is also occasionally useful to represent past information since it may be the only known presence information; it may give watchers an indication of the current status. For example, indicating that the presentity was at an off-site meeting that ended an hour ago indicates that the presentity is likely in transit at the current time. It is unfortunately not possible to simply add time range attributes to the PIDF element, as PIDF parsers without this capability would ignore thes attributes and thus not be able to distinguish current from future presence status information. This document defines the element that describes the status of a presentity that is either no longer valid or covers some future time period. Schulzrinne Expires December 28, 2005 [Page 3] Internet-Draft Timed Presence June 2005 2. Terminology and Conventions The key words MUST, MUST NOT, REQUIRED, SHOULD, SHOULD NOT, RECOMMENDED, MAY, and OPTIONAL in this document are to be interpreted as described in BCP 14, RFC 2119 [1]. Schulzrinne Expires December 28, 2005 [Page 4] Internet-Draft Timed Presence June 2005 3. Timed-Status Element The element is a child of the element and MUST NOT appear as a child of a PIDF element or another element. More than one such element MAY appear within a PIDF element. Sources of information should avoid overlapping elements, but since overlapping appointments are common in calendars, for example, receivers MUST be able to render such overlapping indications. The element MUST be qualified with the 'from' attribute and MAY be qualified with an 'until' attribute to describe the time when the status assumed this value and the time until which this element is expected to be valid. If the 'until' attribute is missing, the information is assumed valid until the tuple is explicitly overridden or expires as defined by the publication mechanism used. The time range MUST NOT encompass the present time, i.e., the value, as that would provide an unnecessary and confusing alternate mechanism to describe presence. Thus, the 'from' attribute for tuples without an 'until' attribute MUST refer to the future. During composition, a presence agent (PA) may encounter a stored elements that covers the present time. The PA MAY either discard those elements or MAY convert it to a regular element if it considers that information more credible. The element may contain the and elements, as well as any other element that is appropriate as a PIDF extension and that has a limited validity period. Examples include the PIDF-LO [5] extensions for location objects. This extension chose absolute rather than relative times, since relative times would be too hard to keep properly updated when spacing notifications, for example. Implementations SHOULD ascertain whether the time values in the elements are plausible, for example, by checking whether the time stamp in a notification protocol message corresponds to local time and by making sure that they are fully in the past or future, both relative to real time and the time contained in the optional PIDF element. Schulzrinne Expires December 28, 2005 [Page 5] Internet-Draft Timed Presence June 2005 4. Example An example combining PIDF and timed-status is shown below: open closed sip:someone@example.com I'll be in Tokyo next week Schulzrinne Expires December 28, 2005 [Page 6] Internet-Draft Timed Presence June 2005 5. The XML Schema Definition The schema is shown below. Describes timed-status tuple extensions for PIDF. Schulzrinne Expires December 28, 2005 [Page 7] Internet-Draft Timed Presence June 2005 6. IANA Considerations This document calls for IANA to register a new XML namespace URN and schema per [2]. 6.1 URN Sub-Namespace Registration for 'urn:ietf:params:xml:ns:pidf:timed-status' URI: urn:ietf:params:xml:ns:pidf:timed-status Description: This is the XML namespace for XML elements defined by RFCXXXX to describe timed-status presence information extensions for the status element in the PIDF presence document format in the application/pidf+xml content type. Registrant Contact: IETF, SIMPLE working group, simple@ietf.org; Henning Schulzrinne, hgs@cs.columbia.edu XML: BEGIN Timed Presence Extensions to the Presence Information Data Format (PIDF) to Indicate Presence Information for Past and Future Time Intervals

Namespace for timed-status presence extension

urn:ietf:params:xml:ns:pidf:timed-status

See RFCXXXX.

END 6.2 Schema Registration for Schema urn:ietf:params:xml:ns:pidf:timed-status' Schulzrinne Expires December 28, 2005 [Page 8] Internet-Draft Timed Presence June 2005 URI: please assign Registrant Contact: IESG XML: See Section 5 Schulzrinne Expires December 28, 2005 [Page 9] Internet-Draft Timed Presence June 2005 7. Security Considerations The security issues are similar to those for RPID [6]. Schulzrinne Expires December 28, 2005 [Page 10] Internet-Draft Timed Presence June 2005 8. References 8.1 Normative References [1] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [2] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688, January 2004. [3] Sugano, H., Fujimoto, S., Klyne, G., Bateman, A., Carr, W., and J. Peterson, "Presence Information Data Format (PIDF)", RFC 3863, August 2004. 8.2 Informative References [4] Rosenberg, J., "A Data Model for Presence", draft-ietf-simple-presence-data-model-02 (work in progress), February 2005. [5] Peterson, J., "A Presence-based GEOPRIV Location Object Format", draft-ietf-geopriv-pidf-lo-03 (work in progress), September 2004. [6] Schulzrinne, H., "RPID: Rich Presence Extensions to the Presence Information Data Format (PIDF)", draft-ietf-simple-rpid-06 (work in progress), June 2005. [7] Schulzrinne, H., "CIPID: Contact Information in Presence Information Data Format", draft-ietf-simple-cipid-04 (work in progress), June 2005. Author's Address Henning Schulzrinne Columbia University Department of Computer Science 450 Computer Science Building New York, NY 10027 US Phone: +1 212 939 7004 Email: hgs+simple@cs.columbia.edu URI: http://www.cs.columbia.edu Schulzrinne Expires December 28, 2005 [Page 11] Internet-Draft Timed Presence June 2005 Appendix A. Contributors Jonathan Rosenberg dynamicsoft 600 Lanidex Plaza Parsippany, NJ 07054-2711 USA Email: jdrosen@dynamicsoft.com Schulzrinne Expires December 28, 2005 [Page 12] Internet-Draft Timed Presence June 2005 Appendix B. Acknowledgments This document is based on the discussions within the IETF SIMPLE working group. Mary Barnes, Miguel Garcia, Vijay Gurbani, Hisham Khartabil, Paul Kyzivat, Mikko Lonnfors, Yannis Pavlidis and Jon Peterson provided helpful comments. Schulzrinne Expires December 28, 2005 [Page 13] Internet-Draft Timed Presence June 2005 Intellectual Property Statement 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 ietf-ipr@ietf.org. Disclaimer of Validity 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 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. Copyright Statement Copyright (C) The Internet Society (2005). 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. Acknowledgment Funding for the RFC Editor function is currently provided by the Internet Society. Schulzrinne Expires December 28, 2005 [Page 14]