<?xml version='1.0' encoding='UTF-8'?> <!DOCTYPE xep SYSTEM 'xep.dtd' [ <!ENTITY % ents SYSTEM 'xep.ent'> %ents; ]> <?xml-stylesheet type='text/xsl' href='xep.xsl'?> <xep> <header> <title>Jingle Grouping Framework</title> <abstract>This specification provides an XML mapping for translating the RFC 5888 SDP Grouping Framework to Jingle</abstract> &LEGALNOTICE; <number>0338</number> <status>Deferred</status> <type>Standards Track</type> <sig>Standards</sig> <approver>Council</approver> <dependencies> <spec>XEP-0166</spec> </dependencies> <supersedes/> <supersededby/> <shortname>NOT_YET_ASSIGNED</shortname> &fippo; <revision> <version>0.2</version> <date>2017-09-11</date> <initials>XEP Editor (jwi)</initials> <remark>Defer due to lack of activity.</remark> </revision> <revision> <version>0.1</version> <date>2014-01-08</date> <initials>psa</initials> <remark><p>Initial published version approved by the XMPP Council.</p></remark> </revision> <revision> <version>0.0.1</version> <date>2013-11-25</date> <initials>ph</initials> <remark><p>First draft.</p></remark> </revision> </header> <section1 topic="Introduction" anchor="intro"> <p>&rfc5888; defines a framework to group SDP 'm' lines for different purposes. A mapping to Jingle as an extension to &xep0166; is defined in this document.</p> <p>It is anticipated that the primary use of this is with the &bundle; framework used in WebRTC.</p> </section1> <section1 topic='Mapping to Session Description Protocol' anchor='sdp'> <p>The SDP format defined in <cite>RFC 5888</cite> is shown below.</p> <code> a=group:semantics identification-tag </code> <p>An example follows.</p> <code> a=group:LS voice webcam </code> <p>This SDP attribute is translated to Jingle as a <group/> element qualified by the 'urn:xmpp:jingle:apps:grouping:0' namespace, as shown below. The semantics is mapped to a 'semantics' attribute. The identification-tags are mapped to content elements whose name attribute is set to the identification-tag.</p> <code><![CDATA[ <group xmlns='urn:xmpp:jingle:apps:grouping:0' semantics='semantics'> <content name='identification-tag 1'/> <content name='identification-tag 2'/> </group> ]]></code> <p>An example follows.</p> <code><![CDATA[ <group xmlns='urn:xmpp:jingle:apps:grouping:0' semantics='LS'> <content name='voice'/> <content name='webcam'/> </group> ]]></code> <p>The <group/> element is included as child of the <jingle/> element.</p> <code><![CDATA[ <iq from='romeo@montague.lit/orchard' id='rg6s5134' to='juliet@capulet.lit/balcony' type='set'> <jingle xmlns='urn:xmpp:jingle:1' action='session-initiate' initiator='romeo@montague.lit/orchard' sid='a73sjjvkla37jfea'> <group xmlns='urn:xmpp:jingle:apps:grouping:0' semantics='BUNDLE'> <content name='voice'/> <content name='webcam'/> </group> <content creator='initiator' name='voice'> [ ... ] </content> <content creator='initiator' name='webcam'> [ ... ] </content> </jingle> </iq> ]]></code> <p>Note: the identification-tags correspond to the <content/> 'name' attributes. These in turn map to the 'mid' attribute in SDP.</p> </section1> <section1 topic='Determining Support' anchor='disco'> <p>If an entity supports the grouping framework described in <cite>RFC 5888</cite>, it MUST advertise that fact in its responses to &xep0030; information ("disco#info") requests by returning a feature of 'urn:ietf:rfc:5888':</p> <example caption='A disco#info query'><![CDATA[ <iq type='get' from='calvin@usrobots.lit/lab' to='herbie@usrobots.lit/home' id='disco1'> <query xmlns='http://jabber.org/protocol/disco#info'/> </iq> ]]></example> <example caption='A disco#info response'><![CDATA[ <iq type='result' from='herbie@usrobots.lit/home' to='calvin@usrobots.lit/lab' id='disco1'> <query xmlns='http://jabber.org/protocol/disco#info'> <feature var='urn:xmpp:jingle:1'/> <feature var='urn:ietf:rfc:5888'/> </query> </iq> ]]></example> <p>In order for an application to determine whether an entity supports this protocol, where possible it SHOULD use the dynamic, presence-based profile of service discovery defined in &xep0115;. However, if an application has not received entity capabilities information from an entity, it SHOULD use explicit service discovery instead.</p> </section1> <section1 topic='Acknowledgements' anchor='acks'> <p>Thanks to Emil Ivov and Lance Stout for their feedback.</p> <p>The XML format for this specification originates from <cite>libjingle</cite><note>libjingle is now part of the WebRTC Native Code Package available from <link url='http://webrtc.org'>webrtc.org</link>.</note>.</p> </section1> <section1 topic='Security Considerations' anchor='security'> <p>This document introduces no additional security considerations above and beyond those defined in the documents on which it depends.</p> </section1> <section1 topic='IANA Considerations' anchor='iana'> <p>This document requires no interaction with &IANA;.</p> </section1> <section1 topic='XMPP Registrar Considerations' anchor='registrar'> <section2 topic='Protocol Namespaces' anchor='registrar-ns'> <p>This specification defines the following XML namespace:</p> <ul> <li>urn:xmpp:jingle:apps:grouping:0</li> </ul> <p>The ®ISTRAR; includes the foregoing namespace to the registry located at &NAMESPACES;, as described in Section 4 of &xep0053;.</p> </section2> <section2 topic='Protocol Versioning' anchor='registrar-versioning'> &NSVER; </section2> </section1> <section1 topic='XML Schema' anchor='schema'> <p>TODO</p> </section1> </xep>