Network Working Group A. B. Roach Internet-Draft Mozilla Updates: 6665 (if approved) October 27, 2014 Intended status: Standards Track Expires: April 30, 2015 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 Abstract Experience since the publication of the most recent SIP Events framework has shown that there is room for interpretation around the use of Globally Routable User Agent URIs in that specification. This document clarifies the intended behavior. This document updates RFC 6665. Status of This Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. 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 April 30, 2015. Copyright Notice Copyright (c) 2014 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 carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must Roach Expires April 30, 2015 [Page 1] Internet-Draft SIP Events GRUU Clarification October 2014 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. Clarification of GRUU Handling . . . . . . . . . . . . . . . 2 2. Security Considerations . . . . . . . . . . . . . . . . . . . 2 3. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 3 4. Normative References . . . . . . . . . . . . . . . . . . . . 3 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Clarification of GRUU Handling 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]. [RFC6665] section 4.5.1 contains the following normative requirement on implementations: Notifiers MUST implement the Globally Routable User Agent URI (GRUU) extension defined in [RFC5627], and MUST use a GRUU as their local target. This allows subscribers to explicitly target desired devices. The second sentence of this paragraph attempted to set context for the normative statement: the reason GRUUs are required in this context is to allow you to send SUBSCRIBE or REFER requests to a specific user agent, with the target of the subscription request being something like an INVITE dialog on that device. Consequently, the requirement to include a GRUU as a local target applies not just to the local target for SUBSCRIBE-created dialogs, but for *all* dialogs, even those created by INVITE. However, this requirement has been interpreted in a variety of ways by implementors, so a clarification is in order. This document updates [RFC6665] to clarify the actual requirement: "Notifiers MUST implement the Globally Routable User Agent URI (GRUU) extension defined in [RFC5627], and MUST use a GRUU as their local target for all dialog-forming methods and all target-refresh methods. This specifically includes dialogs created by the INVITE method." 2. Security Considerations This mechanism does not introduce any security issues beyond those discussed in [RFC6665]. Roach Expires April 30, 2015 [Page 2] Internet-Draft SIP Events GRUU Clarification October 2014 3. IANA Considerations This document requests no actions of IANA. 4. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [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.B., "SIP-Specific Event Notification", RFC 6665, July 2012. Author's Address Adam Roach Mozilla Dallas, TX US Phone: +1 650 903 0800 x863 Email: adam@nostrum.com Roach Expires April 30, 2015 [Page 3]