--- 1/draft-ietf-sipcore-refer-clarifications-03.txt 2015-04-22 08:15:14.404186375 -0700 +++ 2/draft-ietf-sipcore-refer-clarifications-04.txt 2015-04-22 08:15:14.424186856 -0700 @@ -1,19 +1,19 @@ Network Working Group R. Sparks Internet-Draft Oracle Updates: 3515 (if approved) A. Roach Intended status: Standards Track Mozilla -Expires: September 4, 2015 March 3, 2015 +Expires: October 24, 2015 April 22, 2015 Clarifications for the use of REFER with RFC6665 - draft-ietf-sipcore-refer-clarifications-03 + draft-ietf-sipcore-refer-clarifications-04 Abstract The SIP REFER method relies on the SIP-Specific Event Notification Framework. That framework was revised by RFC6665. This document highlights the implications of the requirement changes in RFC6665, and updates the definition of the REFER method, RFC3515, to clarify and disambiguate the impact of those changes. Status of This Memo @@ -24,21 +24,21 @@ Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at http://datatracker.ietf.org/drafts/current/. 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." - This Internet-Draft will expire on September 4, 2015. + This Internet-Draft will expire on October 24, 2015. Copyright Notice Copyright (c) 2015 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents @@ -47,28 +47,29 @@ include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Conventions and Definitions . . . . . . . . . . . . . . . . . 2 2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 3. Use of GRUU is mandatory . . . . . . . . . . . . . . . . . . 3 4. Dialog reuse is prohibited . . . . . . . . . . . . . . . . . 3 - 5. Security Considerations . . . . . . . . . . . . . . . . . . . 4 - 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 4 - 7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 4 - 8. Changelog . . . . . . . . . . . . . . . . . . . . . . . . . . 4 - 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 5 - 9.1. Normative References . . . . . . . . . . . . . . . . . . 5 - 9.2. Informative References . . . . . . . . . . . . . . . . . 6 - Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 6 + 5. The 202 response code is deprecated . . . . . . . . . . . . . 4 + 6. Security Considerations . . . . . . . . . . . . . . . . . . . 4 + 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 4 + 8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 4 + 9. Changelog . . . . . . . . . . . . . . . . . . . . . . . . . . 5 + 10. References . . . . . . . . . . . . . . . . . . . . . . . . . 6 + 10.1. Normative References . . . . . . . . . . . . . . . . . . 6 + 10.2. Informative References . . . . . . . . . . . . . . . . . 6 + Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 7 1. Conventions and Definitions 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]. 2. Introduction The SIP REFER method relies on the SIP-Specific Event Notification @@ -152,47 +153,63 @@ target is a GRUU). Such a REFER will be constructed with its Contact header field populated with the dialog's Local URI as specified in section 12 of [RFC3261]. As described in section 4.5.2 of [RFC6665], there are cases where a user agent may fall back to sharing existing dialogs for backwards- compatibility purposes. This applies to REFER only when the peer has not provided a GRUU as its Contact in the existing dialog (i.e. when the peer is a pre-RFC6665 implementation). -5. Security Considerations +5. The 202 response code is deprecated + + Section 8.3.1 of [RFC6665] requires that elements do not send a 202 + response code to a subscribe request, but use the 200 response code + instead. Any 202 response codes received to a subscribe request are + treated as 200s. These changes also apply to REFER. Specifically, + an element accepting a REFER request MUST NOT reply with a 202 + response code and MUST treat any 202 responses received as identical + to a 200 response. Wherever [RFC3515] requires sending a 202 + response code, a 200 response code MUST be sent instead. + +6. Security Considerations This document introduces no new security considerations directly. The updated considerations in [RFC6665] apply to the implicit subscription created by an accepted REFER request. -6. IANA Considerations +7. IANA Considerations This document has no actions for IANA. -7. Acknowledgements +8. Acknowledgements Christer Holmberg provided the formulation for the final paragraph of the introduction. Christer Holmberg and Ivo Sedlacek provided detailed comments during working group discussion of the document. -8. Changelog +9. Changelog RFC Editor - please remove this section when formatting this document as an RFC + -03 to -04 + + Added section on deprecating 202. + -02 to -03 Reinforced that the MAY send in-dialog applied no matter what the remote target URI contained. -01 to -02 + Tweaked the third paragraph of section 3 per list discussion. (Note the subject line of that discussion said -explicit- subscription) -00 to -01 Added the 3rd paragraph to the introduction per extensive list discussion draft-sparks-sipcore-refer-clarifications-05 to draft-ietf- @@ -200,30 +217,31 @@ Attempted to improve the accuracy of the Abstract and Introduction without diluting the essential point of the document. Added an informative reference to RFC5057. Adjusted text to more reflect what RFC6665 (as clarified by draft-roach-sipcore-6665-clarification) actually requires, and added a normative reference to that clarification draft. + Specifically, the requirement for the _sender_ of a REFER to use a GRUU as its local targetwas removed. Clarified why the explicit-subscription extensions relieve an in-dialog REFERer from the 6665 requirements for using GRUU as its contact in the INVITE dialog. -9. References +10. References -9.1. Normative References +10.1. Normative References [I-D.roach-sipcore-6665-clarification] Roach, A., "A clarification on the use of Globally Routable User Agent URIs (GRUUs) in the Session Initiation Protocol (SIP) Event Notification Framework", draft-roach- sipcore-6665-clarification-00 (work in progress), October 2014. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. @@ -240,21 +258,21 @@ Identification in the Session Initiation Protocol (SIP)", RFC 4538, June 2006. [RFC5627] Rosenberg, J., "Obtaining and Using Globally Routable User Agent URIs (GRUUs) in the Session Initiation Protocol (SIP)", RFC 5627, October 2009. [RFC6665] Roach, A., "SIP-Specific Event Notification", RFC 6665, July 2012. -9.2. Informative References +10.2. Informative References [I-D.ietf-sipcore-refer-explicit-subscription] Sparks, R., "Explicit Subscriptions for the REFER Method", draft-ietf-sipcore-refer-explicit-subscription-00 (work in progress), November 2014. [RFC4488] Levin, O., "Suppression of Session Initiation Protocol (SIP) REFER Method Implicit Subscription", RFC 4488, May 2006.