SIMPLE Working Group S. Loreto Internet-Draft Ericsson Intended status: Standards Track Jan 15, 2009 Expires: July 19, 2009 Internet Assigned Numbers Authority (IANA) Registration of Instant Messaging and Presence DNS SRV RRs for the Session Initiation Protocol (SIP) draft-loreto-simple-im-srv-label-03 Status of this Memo This Internet-Draft is submitted to IETF in full conformance with the provisions of BCP 78 and 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 July 19, 2009. Copyright Notice Copyright (c) 2009 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. Loreto Expires July 19, 2009 [Page 1] Internet-Draft IANA SRV label for SIP Jan 2009 Abstract This document registers with IANA two new DNS SRV Protocol Labels for resolving Instant Messaging and Presence services with SIP. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . 3 3. DNS SRV usage of SIP with 'im' and 'pres' URIs . . . . . . . . 3 4. Security Considerations . . . . . . . . . . . . . . . . . . . . 4 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 4 5.1. Instant Messaging SRV Protocol Label Registration . . . . . 4 5.2. Presence SRV Protocol Label Registration . . . . . . . . . 5 6. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . 5 7. Normative References . . . . . . . . . . . . . . . . . . . . . 5 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 6 Loreto Expires July 19, 2009 [Page 2] Internet-Draft IANA SRV label for SIP Jan 2009 1. Introduction The Service Record (SRV) [RFC2782] identifies the host(s) that will support particular services. The DNS is queried for SRV RR in the general form: _Service._Proto.Name Service: the symbolic name of the desired service. Proto: the protocol of the desired service Name: the domain name for which this record is valid. Address Resolution for Instant Messaging and Presence [RFC3861] provides guidance for locating the services associated with URIs that employ two Uniform Resource Identifier (URI) [RFC3986]: 'im' for INSTANT INBOXes [RFC3860] and 'pres' for PRESENTITIES [RFC3859]. In order to ensure that the association between "_im" and "_pres" and their respective underlying services are deterministic, the IANA has created two independent registries: the Instant Messaging SRV Protocol Label registry and the Presence SRV Protocol Label registry. This document defines and registers the "_sip" protocol label in both registries so that computer programs can resolve 'im:' and 'pres:' URIs down to SIP addresses. Moreover this document explains how the SIP usage for Presence and Instant Messaging protocol uses SRV. 2. 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 [RFC2119]. 3. DNS SRV usage of SIP with 'im' and 'pres' URIs Altough there are standard procedures for resolving im and pres URI (section 3 of [RFC3861]), the labels for SIP are not registered. Section 5 of [RFC3428] states that if a UA is presented with an IM URI (e.g."im:fred@example.com") as the address for an instant message, it SHOULD resolve it to a SIP URI, and place the resulting URI in the Request-URI of the MESSAGE request before sending". Following the procedures defined in [RFC3861], in order to resolve Loreto Expires July 19, 2009 [Page 3] Internet-Draft IANA SRV label for SIP Jan 2009 the IM URI the UA performs a SRV lookup for: _im._sip.example.com Assuming that the example.com domain offers a SIP service for instant messaging at simple.example.com, this will result in a resolution of _im._sip.example.com. to simple.example.com. Thus the instant messaging URI im:fred@example.com would resolve to a SIP URI of sip:fred@simple.example.com. Section 5 of [RFC3856] states that procedures defined in [RFC3861] are also used to resolve the protocol-independent PRES URI for a presentity (e.g. "pres:fred@example.com") into a SIP URI. Following the procedures defined in [RFC3861], in order to resolve the PRES URI the UA performs a SRV lookup for: _pres._sip.example.com Assuming that the example.com domain offers a SIP presence service at simple.example.com, this will result in a resolution of _pres._sip.example.com. to simple.example.com. Thus the protocol independent PRES URI pres:fred@example.com would resolve to a SIP URI of sip:fred@simple.example.com. 4. Security Considerations This document merely serves for the registration of DNS SRV labels in the appropriate IANA registry. The document does not specify a protocol, therefore, there are no security issues associated with it. 5. IANA Considerations This specification registers a new SRV Protocol Label in each of the Instant Messaging SRV Protocol Label registry and the Presence SRV Protocol Label registry, respectively. 5.1. Instant Messaging SRV Protocol Label Registration Address Resolution for Instant Messaging and Presence[RFC3861] defines an Instant Messaging SRV Protocol Label registry for protocols that can provide services that conform to the "_im" SRV Service label. Because SIP is one such protocol, IANA registers the "_sip" protocol label in the "Instant Messaging SRV Protocol Label Registry", as follows: Loreto Expires July 19, 2009 [Page 4] Internet-Draft IANA SRV label for SIP Jan 2009 Protocol label: _sip Specification: RFCXXXX Description: Instant messaging protocol label for the SIP usage for Presence and Instant Messaging protocol as defined by [RFC3428]. Registrant Contact: Salvatore Loreto 5.2. Presence SRV Protocol Label Registration Address Resolution for Instant Messaging and Presence [RFC3861] defines a Presence SRV Protocol Label registry for protocols that can provide services that conform to the "_pres" SRV Service label. Because SIP usage for Presence and Instant Messaging is one such protocol, the IANA registers the "_sip" protocol label in the "Presence SRV Protocol Label Registry", as follows: Protocol label: _sip Specification: RFCXXXX Description: Presence protocol label for the SIP usage for Presence and Instant Messaging protocol as defined by [RFC3856]. Registrant Contact: Salvatore Loreto Note to RFC editor: Please replace RFCXXXX with the RFC number assigned to this document. 6. Acknowledgments The need for this registration was discussed with Jon Peterson and Peter Saint-Andre. Miguel Garcia reviewed this document on behalf of the Real-time Applications and Infrastructure (RAI) Area Review Team (ART). 7. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC2782] Gulbrandsen, A., Vixie, P., and L. Esibov, "A DNS RR for specifying the location of services (DNS SRV)", RFC 2782, February 2000. [RFC3428] Campbell, B., Rosenberg, J., Schulzrinne, H., Huitema, C., and D. Gurle, "Session Initiation Protocol (SIP) Extension for Instant Messaging", RFC 3428, December 2002. [RFC3856] Rosenberg, J., "A Presence Event Package for the Session Loreto Expires July 19, 2009 [Page 5] Internet-Draft IANA SRV label for SIP Jan 2009 Initiation Protocol (SIP)", RFC 3856, August 2004. [RFC3859] Peterson, J., "Common Profile for Presence (CPP)", RFC 3859, August 2004. [RFC3860] Peterson, J., "Common Profile for Instant Messaging (CPIM)", RFC 3860, August 2004. [RFC3861] Peterson, J., "Address Resolution for Instant Messaging and Presence", RFC 3861, August 2004. [RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform Resource Identifier (URI): Generic Syntax", STD 66, RFC 3986, January 2005. Author's Address Salvatore Loreto Ericsson Hirsalantie 11 Jorvas 02420 Finland Email: Salvatore.Loreto@ericsson.com Loreto Expires July 19, 2009 [Page 6]