SIMPLE WG O. Levin
Internet-Draft Microsoft Corporation
Expires: March 31, 2004 Oct 2003
Ad-hoc Resource Lists using SUBSCRIBE in SIMPLE
draft-levin-simple-adhoc-list-00.txt
Status of this Memo
This document is an Internet-Draft and is in full conformance with
all provisions of Section 10 of RFC2026.
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 March 31, 2004.
Copyright Notice
Copyright (C) The Internet Society (2003). All Rights Reserved.
Abstract
This document presents an extension to the Session Initiation
Protocol (SIP)-Specific Event Notification mechanism for subscribing
to a homogeneous list of resources. Instead of the subscriber
sending a SUBSCRIBE for each resource individually, the subscriber
can define an ad-hoc resource list, subscribe to it, and maintain it
û all within a single SUBSCRIBE dialog. Changes in the state of the
resources are reported using the same dialog in any standard SIMPLE
format for conveying notifications for lists of resources or
individual resources and agreed during the SUBSCRIBE dialog
establishment.
Levin Expires March 31, 2004 [Page 1]
Internet-Draft Ad-hoc Resource Lists using SUBSCRIBE Oct 2003
Table of Contents
1. Conventions and Terminology . . . . . . . . . . . . . . . . . 3
2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Overview of Operation . . . . . . . . . . . . . . . . . . . . 3
4. XML Schema . . . . . . . . . . . . . . . . . . . . . . . . . . 4
4.1 Formal Definition . . . . . . . . . . . . . . . . . . . . . . 4
4.2 Example . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
5. Security Considerations . . . . . . . . . . . . . . . . . . . 5
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 6
6.1 New SIP Option Tag: adhoclist . . . . . . . . . . . . . . . . 6
6.2 New MIME type for Resource List Meta-Information . . . . . . . 6
6.3 URN Sub-Namespace . . . . . . . . . . . . . . . . . . . . . . 7
7. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 8
Normative References . . . . . . . . . . . . . . . . . . . . . 8
Informational References . . . . . . . . . . . . . . . . . . . 8
Author's Address . . . . . . . . . . . . . . . . . . . . . . . 9
Intellectual Property and Copyright Statements . . . . . . . . 10
Levin Expires March 31, 2004 [Page 2]
Internet-Draft Ad-hoc Resource Lists using SUBSCRIBE Oct 2003
1. Conventions and Terminology
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 RFC-2119 [2].
This document uses the Resource List Server (RLS) definition from
[8].
2. Introduction
This document presents an extension to the Session Initiation
Protocol (SIP)-Specific Event Notification mechanism for subscribing
to a homogeneous list of resources. Instead of the subscriber
sending a SUBSCRIBE for each resource individually, the subscriber
can define an ad-hoc resource list, subscribe to it, and maintain it
û all within a single SUBSCRIBE dialog. Changes in the state of the
resources are reported using the same dialog in any standard SIMPLE
format for conveying notifications for lists of resources (such as
[8] and [9]) or individual resources (such as [6]) and agreed during
the SUBSCRIBE dialog establishment.
This document defines a new XML schema for creation and maintenance
of a homogeneous list of resources and a new SIP option tag for
expressing support for this schema.
3. Overview of Operation
Before using the ad-hoc list subscription, a subscriber needs to know
that the RLS supports this mode of operation. In order to do so, the
subscriber SHOULD issue OPTIONS request and ensure that the SIP
"adhoclist" option tag is included in the RLS response.
Once the subscriber knows that the RLS supports ad-hoc list
operations, a Require header MUST be set to "adhoclist" and an
initial resources list can be included in the SUBSCRIBE.
It is the responsibility of the subscriber to create the list name.
The value in the Request URI of SUBSCRIBE together with the list
"name" MUST uniquely identify the list.
Note that the exact notification mechanism and the notifications'
format is negotiated by including appropriate SIP option tags in the
Accept headers of SUBSCRIBE and corresponding Responses.
The RLS MUST store and maintain the ad-hoc list for the life of the
SUBSCRIBE dialog. The subscriber MAY update the list by using the
defined add, delete, and reset operations. "Reset" operation means
Levin Expires March 31, 2004 [Page 3]
Internet-Draft Ad-hoc Resource Lists using SUBSCRIBE Oct 2003
that the list MUST be emptied (and created using the new context if
included).
When a resource is added to /deleted from the list, the RLS SHOULD
generate a NOTIFY as if the list had been updated by any possible
out-of-band means and in accordance with the notification mechanism
and format established for this list. The updated information SHOULD
be sent to all the parties being subscribed to this list (including
the "list-owner").
4. XML Schema
4.1 Formal Definition
The schema for the adrl+xml XML document is given below.
See RFCXXXX.
END 7. Acknowledgments Many thanks to Dhigha Sekaran and Sean Olson. Normative References [1] 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. [2] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [3] Rosenberg, J., Schulzrinne, H. and P. Kyzivat, "Caller Preferences for the Session Initiation Protocol (SIP)", draft-ietf-sip-callerprefs-09 (work in progress), July 2003. Informational References [4] Levinson, E., "SGML Media Types", RFC 1874, December 1995. [5] Murata, M., St. Laurent, S. and D. Kohn, "XML Media Types", RFC 3023, January 2001. [6] Sugano, H. and S. Fujimoto, "Presence Information Data Format (PIDF)", draft-ietf-impp-cpim-pidf-08 (work in progress), May 2003. Levin Expires March 31, 2004 [Page 8] Internet-Draft Ad-hoc Resource Lists using SUBSCRIBE Oct 2003 [7] Rosenberg, J., "A Presence Event Package for the Session Initiation Protocol (SIP)", draft-ietf-simple-presence-10 (work in progress), January 2003. [8] Roach, A., Rosenberg, J. and B. Campbell, "A Session Initiation Protocol (SIP) Event Notification Extension for Resource Lists", draft-ietf-simple-event-list-04 (work in progress), June 2003. [9] Lonnfors, M., "Partial Notification of Presence Information", draft-ietf-simple-partial-notify-00 (work in progress), September 2003. Author's Address Orit Levin Microsoft Corporation One Microsoft Way Redmond, WA 98052 USA EMail: oritl@microsoft.com Levin Expires March 31, 2004 [Page 9] Internet-Draft Ad-hoc Resource Lists using SUBSCRIBE Oct 2003 Intellectual Property Statement The IETF takes no position regarding the validity or scope of any intellectual property 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; neither does it represent that it has made any effort to identify any such rights. Information on the IETF's procedures with respect to rights in standards-track and standards-related documentation can be found in BCP-11. Copies of claims of rights made available for publication 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 implementors or users of this specification can be obtained from the IETF Secretariat. The IETF invites any interested party to bring to its attention any copyrights, patents or patent applications, or other proprietary rights which may cover technology that may be required to practice this standard. Please address the information to the IETF Executive Director. Full Copyright Statement Copyright (C) The Internet Society (2003). All Rights Reserved. This document and translations of it may be copied and furnished to others, and derivative works that comment on or otherwise explain it or assist in its implementation may be prepared, copied, published and distributed, in whole or in part, without restriction of any kind, provided that the above copyright notice and this paragraph are included on all such copies and derivative works. However, this document itself may not be modified in any way, such as by removing the copyright notice or references to the Internet Society or other Internet organizations, except as needed for the purpose of developing Internet standards in which case the procedures for copyrights defined in the Internet Standards process must be followed, or as required to translate it into languages other than English. The limited permissions granted above are perpetual and will not be revoked by the Internet Society or its successors or assignees. This document and the information contained herein is provided on an "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION Levin Expires March 31, 2004 [Page 10] Internet-Draft Ad-hoc Resource Lists using SUBSCRIBE Oct 2003 HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Acknowledgment Funding for the RFC Editor function is currently provided by the Internet Society. Levin Expires March 31, 2004 [Page 11]