moparisthebest/xeps
1
0
Fork 0
mirror of https://github.com/moparisthebest/xeps synced 2024-12-21 15:18:51 -05:00
Code Issues Releases Wiki Activity

0.11

Browse Source 
git-svn-id: file:///home/ksmith/gitmigration/svn/xmpp/trunk@1383 4b5297f7-1745-476d-ba37-a9c6900126ab
This commit is contained in:
Peter Saint-Andre 2007-11-15 23:58:28 +00:00
parent a113a1486a
commit c0bc32a180
1 changed files with 763 additions and 39 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

802
xep-0167.xml
View File

@ -25,6 +25,12 @@
&stpeter;
&seanegan;
&robmcqueen;
<revision>
<version>0.11</version>
<date>2007-11-15</date>
<initials>psa</initials>
<remark><p>Editorial review and consistency check; moved voice chat scenarios from XEP-0166 to this specification.</p></remark>
</revision>
<revision>
<version>0.10</version>
<date>2007-11-13</date>
@ -108,18 +114,18 @@
<p>&xep0166; can be used to initiate and negotiate a wide range of peer-to-peer sessions. One session type of interest is audio chat. This document specifies a format for negotiating Jingle audio sessions over the Realtime Transport Protocol (RTP; see &rfc3550;).</p>
</section1>
<section1 topic='Requirements' anchor='reqs'>
<p>The Jingle content description format defined herein is designed to meet the following requirements:</p>
<p>The Jingle application format defined herein is designed to meet the following requirements:</p>
<ol>
<li>Enable negotiation of parameters necessary for audio chat over Realtime Transport Protocol (RTP; see &rfc3550;).</li>
<li>Map these parameters to Session Description Protocol (SDP; see &rfc4566;) to enable interoperability.</li>
<li>Define informational messages related to audio chat (e.g., busy and ringing).</li>
<li>Define informational messages related to audio chat (e.g., ringing, on hold, on mute).</li>
</ol>
</section1>
<section1 topic='Jingle Conformance' anchor='conformance'>
<p>In accordance with Section 8 of <cite>XEP-0166</cite>, this document specifies the following information related to the Jingle Audio via RTP application type:</p>
<ol>
<li><p>The content negotiation process is defined in the <link url='#negotiation'>Negotiating a Jingle Audio Session</link> section of this document.</p></li>
<li><p>The semantics of the &DESCRIPTION; element are defined in the <link url='#format'>Content Description Format</link> section of this document.</p></li>
<li><p>The application format negotiation process is defined in the <link url='#negotiation'>Negotiating a Jingle Audio Session</link> section of this document.</p></li>
<li><p>The semantics of the &DESCRIPTION; element are defined in the <link url='#format'>Application Format</link> section of this document.</p></li>
<li><p>A mapping of Jingle semantics to the Session Description Protocol is provided in the <link url='#sdp'>Mapping to Session Description Protocol</link> section of this document.</p></li>
<li><p>A Jingle audio session SHOULD use a lossy transport method such as &xep0177; or the "ice-udp" method specified in &xep0176;, but MAY use a reliable transport such as "ice-tcp".</p></li>
<li>
@ -131,8 +137,8 @@
</li>
</ol>
</section1>
<section1 topic='Content Description Format' anchor='format'>
<p>A Jingle audio session is described by one or more encodings contained within a wrapper &lt;description/&gt; element. In the language of <cite>RFC 4566</cite> these encodings are payload-types; therefore, each &lt;payload-type/&gt; element specifies an encoding that can be used for the audio stream. In Jingle Audio, these encodings are used in the context of RTP. The most common encodings for the Audio/Video Profile (AVP) of RTP are listed in &rfc3551; (these "static" types are reserved from payload ID 0 through payload ID 95), although other encodings are allowed (these "dynamic" types use payload IDs 96 to 127) in accordance with the dynamic assignment rules described in Section 3 of <cite>RFC 3551</cite>.</p>
<section1 topic='Application Format' anchor='format'>
<p>A Jingle audio session is described by a content type that contains one application format and one transport method. The application format consists of one or more encodings contained within a wrapper &lt;description/&gt; element qualified by the 'http://www.xmpp.org/extensions/xep-0167.html#ns' namespace &NSNOTE;. In the language of <cite>RFC 4566</cite> these encodings are payload-types; therefore, each &lt;payload-type/&gt; element specifies an encoding that can be used for the audio stream. In Jingle Audio, these encodings are used in the context of RTP. The most common encodings for the Audio/Video Profile (AVP) of RTP are listed in &rfc3551; (these "static" types are reserved from payload ID 0 through payload ID 95), although other encodings are allowed (these "dynamic" types use payload IDs 96 to 127) in accordance with the dynamic assignment rules described in Section 3 of <cite>RFC 3551</cite>.</p>
<p>The allowable attributes are as follows:</p>
<table caption='Defined Attributes'>
<tr>
@ -179,7 +185,7 @@
</tr>
</table>
<p>The encodings SHOULD be provided in order of preference.</p>
<example caption="Audio Description Format"><![CDATA[
<example caption="Audio description format"><![CDATA[
<description xmlns='http://www.xmpp.org/extensions/xep-0167.html#ns'>
<payload-type id='96' name='speex' clockrate='16000'/>
<payload-type id='97' name='speex' clockrate='8000'/>
@ -193,7 +199,8 @@
<payload-type id='13' name='CN'/>
</description>
]]></example>
<p>The &lt;description/&gt; element is intended to be a child of a &JINGLE; element as specified in <cite>XEP-0166</cite>.</p>
<p>The &DESCRIPTION; element is intended to be a child of a &JINGLE; element as specified in <cite>XEP-0166</cite>.</p>
<p>The encodings SHOULD be provided in order of preference by placing the most-preferred &PAYLOADTYPE; element as the first child of the &DESCRIPTION; element (etc.).</p>
<p>Each &lt;payload-type/&gt; element MAY contain one or more child elements that specify particular parameters related to the payload. For example, as described in &rtpspeex;, the "cng", "mode", and "vbr" parameters may be specified in relation to usage of the Speex <note>See &lt;<link url='http://www.speex.org/'>http://www.speex.org/</link>&gt;.</note> codec. Where such parameters are encoded via the "fmtp" SDP attribute, they shall be represented in Jingle via the following format:</p>
<code><![CDATA[
<parameter name='foo' value='bar'/>
@ -202,7 +209,7 @@
</section1>
<section1 topic='Negotiating a Jingle Audio Session' anchor='negotiation'>
<p>When the initiator sends a session-initiate stanza to the receiver, the &DESCRIPTION; element includes all of the payload types that the initiator can receive for Jingle audio (each one encapsulated in a separate &PAYLOADTYPE; element):</p>
<example caption="Initiation Example"><![CDATA[
<example caption="Initiation"><![CDATA[
<iq from='romeo@montague.net/orchard'
to='juliet@capulet.com/balcony'
id='jingleaudio1'
@ -224,8 +231,8 @@
</jingle>
</iq>
]]></example>
<p>Upon receiving the session-initiate stanza, the receiver determines whether it can provisionally accept the session and proceed with the negotiation. The general Jingle error cases are specified in <cite>XEP-0166</cite>. In addition, the receiver must determine if it supports any of the payload types advertised by the initiator; if it does not, it MUST reject the session by sending a &lt;unsupported-codecs/&gt; error:</p>
<example caption="Receiver Does Not Support Codecs"><![CDATA[
<p>Upon receiving the session-initiate stanza, the receiver determines whether it can provisionally accept the session and proceed with the negotiation. The general Jingle error cases are specified in <cite>XEP-0166</cite> and illustrated in the <link url='#scenarios'>Scenarios</link> section of this document. In addition, the receiver must determine if it supports any of the payload types advertised by the initiator; if it supports none of the offered payload types, it must reject the session by returning a &notacceptable; error with a Jingle-Audio-specific condition of &lt;unsupported-codecs/&gt;:</p>
<example caption="Receiver does not support any of the codecs"><![CDATA[
<iq type='error'
from='juliet@capulet.com/balcony'
to='romeo@montague.net/orchard'
@ -237,14 +244,14 @@
</iq>
]]></example>
<p>If there is no error, the receiver provisionally accepts the session:</p>
<example caption="Receiver Provisionally Accepts Session"><![CDATA[
<example caption="Receiver provisionally accepts session"><![CDATA[
<iq from='juliet@capulet.com/balcony'
to='romeo@montague.net/orchard'
id='jingleaudio1'
type='result'/>
]]></example>
<p>The receiver then should send a list of the payload types that it can receive via a Jingle "content-accept" (or "session-accept") action. The list that the receiver sends MAY include any payload types (not a subset of the payload types sent by the initiator) but SHOULD retain the ID numbers and order specified by the initiator.</p>
<example caption="Receiver Accepts Content Type"><![CDATA[
<p>The receiver then should send a list of the payload types that it can receive via a Jingle "content-accept" (or "session-accept") action. The list that the receiver sends MAY include any payload types (not a subset of the payload types sent by the initiator) but SHOULD retain the ID numbers specified by the initiator. The order of the &PAYLOADTYPE; elements indicates the receiver's preferences, with the most-preferred types first.</p>
<example caption="Receiver accepts content type"><![CDATA[
<iq from='juliet@capulet.com/balcony'
to='romeo@montague.net/orchard'
id='jingleaudio2'
@ -269,14 +276,14 @@
</iq>
]]></example>
<p>The initiator acknowledges the 'content-accept' with an empty IQ result:</p>
<example caption="Initiator Acknowledges Modified Content Description"><![CDATA[
<example caption="Initiator acknowledges modified application format"><![CDATA[
<iq from='romeo@montegue.net/orchard'
to='juliet@capulet.com/balcony'
id='jingleaudio2'
type='result'/>
]]></example>
<p>After successful transport negotiation (not shown here), the receiver then accepts the session:</p>
<example caption="Receiver Definitively Accepts the Session"><![CDATA[
<example caption="Receiver definitively accepts the session"><![CDATA[
<iq type='set' from='juliet@capulet.com/balcony' to='romeo@montague.net/orchard' id='accept1'>
<jingle xmlns='http://www.xmpp.org/extensions/xep-0166.html#ns'
action='session-accept'
@ -303,43 +310,760 @@
</iq>
]]></example>
<p>And the initiator acknowledges session acceptance:</p>
<example caption="Initiator Acknowledges Session Acceptance"><![CDATA[
<example caption="initiator acknowledges session acceptance"><![CDATA[
<iq from='romeo@montague.net/orchard'
to='juliet@capulet.com/balcony'
id='accept1'
type='result'/>
]]></example>
<p>Note: Because a "session-accept" action implicitly indicates acceptance of the application format (i.e., "content-accept"), it is not necessary to send a separate "content-accept" action. This flow is shown for completeness only.</p>
</section1>
<section1 topic='Scenarios' anchor='scenarios'>
<p>The following sections show a number of Jingle audio scenarios, in relative order of complexity.</p>
<section2 topic='Receiver is Busy' anchor='scenarios-busy'>
<p>In this scenario, Romeo initiates a voice chat with Juliet but she is otherwise engaged.</p>
<p>The session flow is as follows:</p>
<code><![CDATA[
Romeo Juliet
| |
| session-initiate |
|---------------------------->|
| error |
| (recipient-unavailable) |
|<----------------------------|
]]></code>
<p>The protocol flow is as follows.</p>
<example caption="Initiator sends session-initiate"><![CDATA[
<iq from='romeo@montague.lit/orchard' to='juliet@capulet.lit/balcony' id='jingle1' type='set'>
<jingle xmlns='http://www.xmpp.org/extensions/xep-0166.html#ns'
action='session-initiate'
initiator='romeo@montague.lit/orchard'
sid='a73sjjvkla37jfea'>
<content creator='initiator' name='this-is-the-audio-content' profile='RTP/AVP'>
<description xmlns='http://www.xmpp.org/extensions/xep-0167.html#ns'>
<payload-type id='96' name='speex' clockrate='16000'/>
<payload-type id='97' name='speex' clockrate='8000'/>
<payload-type id='18' name='G729'/>
<payload-type id='103' name='L16' clockrate='16000' channels='2'/>
<payload-type id='98' name='x-ISAC' clockrate='8000'/>
</description>
<transport xmlns='http://www.xmpp.org/extensions/xep-0176.html#ns-udp'/>
</content>
</jingle>
</iq>
]]></example>
<example caption="Receiver returns recipient-unavailable error"><![CDATA[
<iq from='juliet@capulet.lit/balcony'
id='accept1'
to='romeo@montague.lit/orchard'
type='error'>
<error type='wait'>
<recipient-unavailable xmlns='urn:ietf:params:xml:ns:xmpp-stanzas'/>
<busy xmlns='http://www.xmpp.org/extensions/xep-0166.html#ns-errors'/>
</error>
</iq>
]]></example>
</section2>
<section2 topic='Jingle Audio via RTP/AVP, Negotiated with ICE-UDP' anchor='scenarios-voicechat'>
<p>In this scenario, Romeo initiates a voice chat with Juliet using a transport method of ICE-UDP. The parties also exchange informational messages.</p>
<p>The session flow is as follows:</p>
<code><![CDATA[
Romeo Juliet
| |
| session-initiate |
|---------------------------->|
| ack |
|<----------------------------|
| session-info (ringing) |
|<----------------------------|
| ack |
|---------------------------->|
| transport-info (X times) |
| (with acks) |
|<--------------------------->|
| session-accept |
|<----------------------------|
| ack |
|---------------------------->|
| AUDIO (RTP) |
|<===========================>|
| session-terminate |
|<----------------------------|
| ack |
|---------------------------->|
| |
]]></code>
<p>The protocol flow is as follows.</p>
<example caption="Initiator sends session-initiate"><![CDATA[
<iq from='romeo@montague.lit/orchard' to='juliet@capulet.lit/balcony' id='jingle1' type='set'>
<jingle xmlns='http://www.xmpp.org/extensions/xep-0166.html#ns'
action='session-initiate'
initiator='romeo@montague.lit/orchard'
sid='a73sjjvkla37jfea'>
<content creator='initiator' name='this-is-the-audio-content' profile='RTP/AVP'>
<description xmlns='http://www.xmpp.org/extensions/xep-0167.html#ns'>
<payload-type id='96' name='speex' clockrate='16000'/>
<payload-type id='97' name='speex' clockrate='8000'/>
<payload-type id='18' name='G729'/>
<payload-type id='103' name='L16' clockrate='16000' channels='2'/>
<payload-type id='98' name='x-ISAC' clockrate='8000'/>
</description>
<transport xmlns='http://www.xmpp.org/extensions/xep-0176.html#ns-udp'/>
</content>
</jingle>
</iq>
]]></example>
<example caption="Receiver sends provisional acceptance"><![CDATA[
<iq from='juliet@capulet.lit/balcony'
id='accept1'
to='romeo@montague.lit/orchard'
type='result'/>
]]></example>
<example caption="Receiver sends ringing message"><![CDATA[
<iq from='juliet@capulet.com/balcony'
to='romeo@montague.net/orchard'
id='ringing1'
type='set'>
<jingle xmlns='http://www.xmpp.org/extensions/xep-0166.html#ns'
action='session-info'
initiator='romeo@montague.net/orchard'
sid='a73sjjvkla37jfea'>
<ringing xmlns='http://www.xmpp.org/extensions/xep-0167.html#ns-info'/>
</jingle>
</iq>
]]></example>
<example caption="Initiator acknowledges ringing message"><![CDATA[
<iq from='romeo@montague.lit/orchard'
id='ringing1'
to='juliet@capulet.lit/balcony'
type='result'/>
]]></example>
<example caption="Initiator sends a candidate"><![CDATA[
<iq from='romeo@montague.lit/orchard'
id='info1'
to='juliet@capulet.lit/balcony'
type='set'>
<jingle xmlns='http://www.xmpp.org/extensions/xep-0166.html#ns'
action='transport-info'
initiator='romeo@montague.lit/orchard'
sid='a73sjjvkla37jfea'>
<content creator='initiator' name='this-is-the-audio-content' profile='RTP/AVP'>
<transport xmlns='http://www.xmpp.org/extensions/xep-0176.html#ns-udp'>
<candidate component='1'
foundation='1'
generation='0'
ip='10.0.1.1'
network='0'
port='8998'
priority='2114978302'
protocol='udp'
pwd='asd88fgpdd777uzjYhagZg'
type='host'
ufrag='8hhy'/>
</transport>
</content>
</jingle>
</iq>
]]></example>
<example caption="Initiator sends a second candidate"><![CDATA[
<iq from='romeo@montague.lit/orchard'
id='info2'
to='juliet@capulet.lit/balcony'
type='set'>
<jingle xmlns='http://www.xmpp.org/extensions/xep-0166.html#ns'
action='transport-info'
initiator='romeo@montague.lit/orchard'
sid='a73sjjvkla37jfea'>
<content creator='initiator' name='this-is-the-audio-content' profile='RTP/AVP'>
<transport xmlns='http://www.xmpp.org/extensions/xep-0176.html#ns-udp'>
<candidate component='1'
foundation='1'
generation='0'
ip='192.0.2.3'
network='1'
port='45664'
priority='1678246398'
protocol='udp'
pwd='asd88fgpdd777uzjYhagZg'
type='srflx'
ufrag='8hhy'/>
</transport>
</content>
</jingle>
</iq>
]]></example>
<example caption="Initiator sends a third candidate"><![CDATA[
<iq from='romeo@montague.lit/orchard'
id='info3'
to='juliet@capulet.lit/balcony'
type='set'>
<jingle xmlns='http://www.xmpp.org/extensions/xep-0166.html#ns'
action='transport-info'
initiator='romeo@montague.lit/orchard'
sid='a73sjjvkla37jfea'>
<content creator='initiator' name='this-is-the-audio-content' profile='RTP/AVP'>
<transport xmlns='http://www.xmpp.org/extensions/xep-0176.html#ns-udp'>
<candidate component='1'
foundation='1'
generation='0'
ip='208.245.212.67'
network='2'
port='53267'
priority='1677984254'
protocol='udp'
pwd='asd88fgpdd777uzjYhagZg'
type='srflx'
ufrag='8hhy'/>
</transport>
</content>
</jingle>
</iq>
]]></example>
<p>For each candidate received, the other party acknowledges receipt or returns an error:</p>
<example caption="Responder acknowledges receipt"><![CDATA[
<iq from='juliet@capulet.lit/balcony' to='romeo@montague.lit/orchard' id='info1' type='result'/>
<iq from='juliet@capulet.lit/balcony' to='romeo@montague.lit/orchard' id='info2' type='result'/>
<iq from='juliet@capulet.lit/balcony' to='romeo@montague.lit/orchard' id='info3' type='result'/>
]]></example>
<p>At the same time (i.e., immediately after provisionally accepting the session, not waiting for the initiator to begin or finish sending candidates), the responder also begins sending candidates that may work for it. As above, the initiator acknowledges receipt of the candidates.</p>
<p>As the initiator and responder receive candidates, they probe the various candidate transports for connectivity. In performing these connectivity checks, the parties follow the procedure specified in Section 7 of <cite>draft-ietf-mmusic-ice</cite>.</p>
<p>If one of the candidate transports is found to work, the receiver accepts the session.</p>
<example caption="Receiver sends session-accept"><![CDATA[
<iq type='set' from='juliet@capulet.lit/balcony' to='romeo@montague.lit/orchard' id='accept1'>
<jingle xmlns='http://www.xmpp.org/extensions/xep-0166.html#ns'
action='session-accept'
initiator='romeo@montague.lit/orchard'
responder='juliet@capulet.lit/balcony'
sid='a73sjjvkla37jfea'>
<content creator='initiator' name='this-is-the-audio-content' profile='RTP/AVP'>
<description xmlns='http://www.xmpp.org/extensions/xep-0167.html#ns'>
<payload-type id='97' name='speex' clockrate='8000'/>
<payload-type id='18' name='G729'/>
<payload-type id='0' name='PCMU' />
<payload-type id='102' name='iLBC'/>
<payload-type id='4' name='G723'/>
<payload-type id='8' name='PCMA'/>
<payload-type id='13' name='CN'/>
</description>
<transport xmlns='http://www.xmpp.org/extensions/xep-0176.html#ns'>
<candidate ip='208.245.212.67' port='9876' generation='0'/>
</transport>
</content>
</jingle>
</iq>
]]></example>
<p>If the payload types and transport candidate can be successfully used by both parties, then the initiator acknowledges the session-accept.</p>
<example caption="Initiator acknowledges session-accept"><![CDATA[
<iq type='result' to='juliet@capulet.lit/balcony' from='romeo@montague.lit/orchard' id='accept1'/>
]]></example>
<p>The parties now begin to exchange media. In this case they would exchange audio using the Speex codec at a clockrate of 8000 since that is the highest-priority codec for the responder (as determined by the XML order of the &PAYLOADTYPE; children).</p>
<p>The parties may continue the session as long as desired.</p>
<p>Eventually, one of the parties terminates the session.</p>
<example caption="Receiver terminates the session"><![CDATA[
<iq from='juliet@capulet.lit/balcony'
id='term1'
to='romeo@montague.lit/orchard'
type='set'>
<jingle xmlns='http://www.xmpp.org/extensions/xep-0166.html#ns'
action='session-terminate'
initiator='romeo@montague.lit/orchard'
reason='Sorry, gotta go!'
sid='a73sjjvkla37jfea'/>
</iq>
]]></example>
<p>The other party then acknowledges termination of the session:</p>
<example caption="Initiator acknowledges termination"><![CDATA[
<iq from='romeo@montague.lit/orchard'
id='term1'
to='juliet@capulet.lit/balcony'
type='result'/>
]]></example>
</section2>
<section2 topic='Jingle Audio and Video via RTP/AVP, Negotiated with ICE-UDP' anchor='scenarios-voicechat'>
<p>In this scenario, Romeo initiates a combined audio and video chat with Juliet using a transport method of ICE. Juliet at first refuses the video portion, then later offers to add video, which Romeo accepts. The parties also exchange various informational messages</p>
<p>The session flow is as follows:</p>
<code><![CDATA[
Romeo Juliet
| |
| session-initiate |
|---------------------------->|
| ack |
|<----------------------------|
| session-info (ringing) |
|<----------------------------|
| ack |
|---------------------------->|
| content-remove |
|<----------------------------|
| ack |
|---------------------------->|
| content-accept |
|---------------------------->|
| ack |
|<----------------------------|
| transport-info (X times) |
| (with acks) |
|<--------------------------->|
| session-accept |
|<----------------------------|
| ack |
|---------------------------->|
| AUDIO (RTP) |
|<===========================>|
| session-info (hold) |
|<----------------------------|
| ack |
|---------------------------->|
| session-info (active) |
|<----------------------------|
| ack |
|---------------------------->|
| content-add |
|<----------------------------|
| ack |
|---------------------------->|
| content-accept |
|---------------------------->|
| ack |
|<----------------------------|
| AUDIO + VIDEO (RTP) |
|<===========================>|
| session-terminate |
|<----------------------------|
| ack |
|---------------------------->|
| |
]]></code>
<p>The protocol flow is as follows.</p>
<example caption="Initiation"><![CDATA[
<iq from='romeo@montague.lit/orchard' to='juliet@capulet.lit/balcony' id='jingle1' type='set'>
<jingle xmlns='http://www.xmpp.org/extensions/xep-0166.html#ns'
action='session-initiate'
initiator='romeo@montague.lit/orchard'
sid='a73sjjvkla37jfea'>
<content creator='initiator' name='this-is-the-audio-content' profile='RTP/AVP'>
<description xmlns='http://www.xmpp.org/extensions/xep-0167.html#ns'>
<payload-type id='96' name='speex' clockrate='16000'/>
<payload-type id='97' name='speex' clockrate='8000'/>
<payload-type id='18' name='G729'/>
<payload-type id='103' name='L16' clockrate='16000' channels='2'/>
<payload-type id='98' name='x-ISAC' clockrate='8000'/>
</description>
<transport xmlns='http://www.xmpp.org/extensions/xep-0176.html#ns'/>
</content>
<content creator='initiator' name='this-is-the-video-content' profile='RTP/AVP'>
<description xmlns='http://www.xmpp.org/extensions/xep-0180.html#ns'>
<payload-type id='96' name='theora' clockrate='90000' height='720' width='1280'>
<parameter name='delivery-method' value='inline'/>
<parameter name='configuration' value='somebase16string'/>
<parameter name='sampling' value='YCbCr-4:2:2'/>
</payload-type>
<payload-type id='28' name='nv' clockrate='90000'/>
<payload-type id='25' name='CelB' clockrate='90000'/>
<payload-type id='32' name='MPV' clockrate='90000'/>
</description>
<transport xmlns='http://www.xmpp.org/extensions/xep-0176.html#ns'/>
</content>
</jingle>
</iq>
]]></example>
<example caption="Receiver acknowledges receipt of initiation request"><![CDATA[
<iq type='result' from='juliet@capulet.lit/balcony' to='romeo@montague.lit/orchard' id='jingle1'/>
]]></example>
<example caption="Receiver sends ringing message"><![CDATA[
<iq from='juliet@capulet.com/balcony'
to='romeo@montague.net/orchard'
id='ringing1'
type='set'>
<jingle xmlns='http://www.xmpp.org/extensions/xep-0166.html#ns'
action='session-info'
initiator='romeo@montague.net/orchard'
sid='a73sjjvkla37jfea'>
<ringing xmlns='http://www.xmpp.org/extensions/xep-0167.html#ns-info'/>
</jingle>
</iq>
]]></example>
<example caption="Initiator acknowledges ringing message"><![CDATA[
<iq from='romeo@montague.lit/orchard'
id='ringing1'
to='juliet@capulet.lit/balcony'
type='result'/>
]]></example>
<p>However, Juliet doesn't want to do video because she is having a bad hair day, so she sends a "content-remove" request to Romeo.</p>
<example caption="Receiver requests content-remove"><![CDATA[
<iq from='juliet@capulet.lit/balcony' to='romeo@montague.lit/orchard' id='remove1' type='set'>
<jingle xmlns='http://www.xmpp.org/extensions/xep-0166.html#ns'
action='content-remove'
initiator='romeo@montague.lit/orchard'
sid='a73sjjvkla37jfea'>
<content creator='initiator' name='this-is-the-video-content' profile='RTP/AVP'/>
</jingle>
</iq>
]]></example>
<p>Romeo then acknowledges the content-remove request and, if it is acceptable, returns a content-accept:</p>
<example caption="Initiator acknowledges content-remove"><![CDATA[
<iq from='romeo@montague.lit/orchard' to='juliet@capulet.lit/balcony' id='remove1' type='result'/>
]]></example>
<example caption="Initiator accepts content definition"><![CDATA[
<iq from='romeo@montague.lit/orchard' to='juliet@capulet.lit/balcony' id='remove2' type='set'>
<jingle xmlns='http://www.xmpp.org/extensions/xep-0166.html#ns'
action='content-accept'
initiator='romeo@montague.lit/orchard'
sid='a73sjjvkla37jfea'>
<content creator='responder' name='this-is-the-video-content' profile='RTP/AVP'>
<description xmlns='http://www.xmpp.org/extensions/xep-0180.html#ns'/>
<transport xmlns='http://www.xmpp.org/extensions/xep-0176.html#ns'/>
</content>
</jingle>
</iq>
]]></example>
<p>The other party then acknowledges the acceptance.</p>
<example caption="Receiver acknowledges content-accept"><![CDATA[
<iq from='juliet@capulet.lit/balcony' to='romeo@montague.lit/orchard' id='remove2' type='result'/>
]]></example>
<p>As in the previous scenario, the parties exchange ICE candidates (see above for examples).</p>
<p>Once the parties find candidate transports that work, the receiver accepts the session.</p>
<example caption="Receiver sends session-accept"><![CDATA[
<iq type='set' from='juliet@capulet.lit/balcony' to='romeo@montague.lit/orchard' id='accept1'>
<jingle xmlns='http://www.xmpp.org/extensions/xep-0166.html#ns'
action='session-accept'
initiator='romeo@montague.lit/orchard'
responder='juliet@capulet.lit/balcony'
sid='a73sjjvkla37jfea'>
<content creator='initiator' name='this-is-the-audio-content' profile='RTP/AVP'>
<description xmlns='http://www.xmpp.org/extensions/xep-0167.html#ns'>
<payload-type id='97' name='speex' clockrate='8000'/>
<payload-type id='18' name='G729'/>
<payload-type id='0' name='PCMU' />
<payload-type id='102' name='iLBC'/>
<payload-type id='4' name='G723'/>
<payload-type id='8' name='PCMA'/>
<payload-type id='13' name='CN'/>
</description>
<transport xmlns='http://www.xmpp.org/extensions/xep-0176.html#ns'>
<candidate ip='208.245.212.67' port='9876' generation='0'/>
</transport>
</content>
</jingle>
</iq>
]]></example>
<p>As above, if the payload types and transport candidate can be successfully used by both parties, then the initiator acknowledges the session-accept.</p>
<example caption="Initiator acknowledges session-accept"><![CDATA[
<iq type='result' to='juliet@capulet.lit/balcony' from='romeo@montague.lit/orchard' id='accept1'/>
]]></example>
<p>The parties now begin to exchange media. In this case they would exchange audio using the Speex codec at a clockrate of 8000 since that is the highest-priority codec for the responder (as determined by the XML order of the &PAYLOADTYPE; children).</p>
<p>Juliet wants to get her hair in order so she puts Romeo on hold.</p>
<example caption="Receiver sends hold message"><![CDATA[
<iq from='juliet@capulet.com/balcony'
to='romeo@montague.net/orchard'
id='hold1'
type='set'>
<jingle xmlns='http://www.xmpp.org/extensions/xep-0166.html#ns'
action='session-info'
initiator='romeo@montague.net/orchard'
sid='a73sjjvkla37jfea'>
<hold xmlns='http://www.xmpp.org/extensions/xep-0167.html#ns-info'/>
</jingle>
</iq>
]]></example>
<example caption="Initiator acknowledges hold message"><![CDATA[
<iq from='romeo@montague.lit/orchard'
id='hold1'
to='juliet@capulet.lit/balcony'
type='result'/>
]]></example>
<p>Juliet returns so she informs Romeo that she is actively engaged in the call again.</p>
<example caption="Receiver sends active message"><![CDATA[
<iq from='juliet@capulet.com/balcony'
to='romeo@montague.net/orchard'
id='active1'
type='set'>
<jingle xmlns='http://www.xmpp.org/extensions/xep-0166.html#ns'
action='session-info'
initiator='romeo@montague.net/orchard'
sid='a73sjjvkla37jfea'>
<active xmlns='http://www.xmpp.org/extensions/xep-0167.html#ns-info'/>
</jingle>
</iq>
]]></example>
<example caption="Initiator acknowledges active message"><![CDATA[
<iq from='romeo@montague.lit/orchard'
id='active1'
to='juliet@capulet.lit/balcony'
type='result'/>
]]></example>
<p>The parties now continue the audio chat.</p>
<p>Finally Juliet decides that she is presentable for a video chat so she sends a content-add request to Romeo.</p>
<example caption="Receiver sends a content-add"><![CDATA[
<iq from='juliet@capulet.lit/balcony' to='romeo@montague.lit/orchard' id='add1' type='set'>
<jingle xmlns='http://www.xmpp.org/extensions/xep-0166.html#ns'
action='content-add'
initiator='romeo@montague.lit/orchard'
sid='a73sjjvkla37jfea'>
<content creator='responder' name='video-is-back' profile='RTP/AVP'>
<description xmlns='http://www.xmpp.org/extensions/xep-0180.html#ns'>
<payload-type id='96' name='theora' height='720' width='1280'>
<parameter name='delivery-method' value='inline'/>
<parameter name='configuration' value='somebase16string'/>
<parameter name='sampling' value='YCbCr-4:2:2'/>
</payload-type>
<payload-type id='32' name='MPV' clockrate='90000'/>
<payload-type id='33' name='MP2T' clockrate='90000'/>
</description>
<transport xmlns='http://www.xmpp.org/extensions/xep-0176.html#ns'>
</content>
</jingle>
</iq>
]]></example>
<p>The entity receiving the content-add request then acknowledges the request and, if it is acceptable, returns a content-accept:</p>
<example caption="Initiator acknowledges content-add"><![CDATA[
<iq from='romeo@montague.lit/orchard' to='juliet@capulet.lit/balcony' id='add1' type='result'/>
]]></example>
<example caption="Initiator accepts content type definition"><![CDATA[
<iq from='romeo@montague.lit/orchard' to='juliet@capulet.lit/balcony' id='add2' type='set'>
<jingle xmlns='http://www.xmpp.org/extensions/xep-0166.html#ns'
action='content-accept'
initiator='romeo@montague.lit/orchard'
sid='a73sjjvkla37jfea'>
<content creator='responder' name='video-is-back' profile='RTP/AVP'>
<description xmlns='http://www.xmpp.org/extensions/xep-0180.html#ns'>
<payload-type id='96' name='theora' height='720' width='1280'>
<parameter name='delivery-method' value='inline'/>
<parameter name='configuration' value='somebase16string'/>
<parameter name='sampling' value='YCbCr-4:2:2'/>
</payload-type>
<payload-type id='32' name='MPV' clockrate='90000'/>
<payload-type id='33' name='MP2T' clockrate='90000'/>
</description>
<transport xmlns='http://www.xmpp.org/extensions/xep-0176.html#ns'/>
</content>
</jingle>
</iq>
]]></example>
<p>The other party then acknowledges the acceptance.</p>
<example caption="Receiver acknowledges content-accept"><![CDATA[
<iq from='juliet@capulet.lit/balcony' to='romeo@montague.lit/orchard' id='add2' type='result'/>
]]></example>
<p>The media session proceeds. Now they would exchange both audio and video, where the audio is exchanged the Speex codec at a clockrate of 8000 and the video is exchanged using the Theora codec with a height of 720 pixels, a width of 1280 pixels, and so on.</p>
<p>The parties may continue the session as long as desired.</p>
<p>Eventually, one of the parties terminates the session.</p>
<example caption="Initiator sends session-terminate"><![CDATA[
<iq from='romeo@montague.lit/orchard'
id='term1'
to='juliet@capulet.lit/balcony'
type='set'>
<jingle xmlns='http://www.xmpp.org/extensions/xep-0166.html#ns'
action='session-terminate'
initiator='romeo@montague.lit/orchard'
reason='I&apos;m outta here!'
sid='a73sjjvkla37jfea'/>
</iq>
]]></example>
<example caption="Receiver acknowledges session-terminate"><![CDATA[
<iq from='juliet@capulet.lit/balcony'
id='term1'
to='romeo@montague.lit/orchard'
type='result'/>
]]></example>
</section2>
<section2 topic='Secure Jingle Audio via UDP/TLS/RTP/AVP, Negotiated with ICE-UDP' anchor='scenarios-secure'>
<p>In this scenario, Romeo initiates a voice chat with Juliet using a transport method of ICE-UDP and an unencrypted profile of "RTP/AVP", but Juliet wants to chat securely so she requests the use of a secure transport as specified in &sdpdtls; (via a profile of "UDP/TLS/RTP/AVP").</p>
<p>The session flow is as follows:</p>
<code><![CDATA[
Romeo Juliet
| |
| session-initiate |
|---------------------------->|
| ack |
|<----------------------------|
| session-info (ringing) |
|<----------------------------|
| ack |
|---------------------------->|
| content-modify |
|<----------------------------|
| ack |
|---------------------------->|
| content-accept |
|---------------------------->|
| ack |
|<----------------------------|
| transport-info (X times) |
| (with acks) |
|<--------------------------->|
| session-accept |
|<----------------------------|
| ack |
|---------------------------->|
| AUDIO (RTP) |
|<===========================>|
| session-terminate |
|<----------------------------|
| ack |
|---------------------------->|
| |
]]></code>
<p>The protocol flow is as follows.</p>
<example caption="Initiator sends session-initiate"><![CDATA[
<iq from='romeo@montague.lit/orchard' to='juliet@capulet.lit/balcony' id='jingle1' type='set'>
<jingle xmlns='http://www.xmpp.org/extensions/xep-0166.html#ns'
action='session-initiate'
initiator='romeo@montague.lit/orchard'
sid='a73sjjvkla37jfea'>
<content creator='initiator' name='this-is-the-audio-content' profile='RTP/AVP'>
<description xmlns='http://www.xmpp.org/extensions/xep-0167.html#ns'>
<payload-type id='96' name='speex' clockrate='16000'/>
<payload-type id='97' name='speex' clockrate='8000'/>
<payload-type id='18' name='G729'/>
<payload-type id='103' name='L16' clockrate='16000' channels='2'/>
<payload-type id='98' name='x-ISAC' clockrate='8000'/>
</description>
<transport xmlns='http://www.xmpp.org/extensions/xep-0176.html#ns-udp'/>
</content>
</jingle>
</iq>
]]></example>
<example caption="Receiver sends provisional acceptance"><![CDATA[
<iq from='juliet@capulet.lit/balcony'
id='accept1'
to='romeo@montague.lit/orchard'
type='result'/>
]]></example>
<example caption="Receiver sends ringing message"><![CDATA[
<iq from='juliet@capulet.com/balcony'
to='romeo@montague.net/orchard'
id='ringing1'
type='set'>
<jingle xmlns='http://www.xmpp.org/extensions/xep-0166.html#ns'
action='session-info'
initiator='romeo@montague.net/orchard'
sid='a73sjjvkla37jfea'>
<ringing xmlns='http://www.xmpp.org/extensions/xep-0167.html#ns-info'/>
</jingle>
</iq>
]]></example>
<example caption="Initiator acknowledges ringing message"><![CDATA[
<iq from='romeo@montague.lit/orchard'
id='ringing1'
to='juliet@capulet.lit/balcony'
type='result'/>
]]></example>
<p>However, Juliet wants to make sure that the communications are encrypted, so she sends a "content-modify" request to Romeo.</p>
<example caption="Receiver requests content-modify"><![CDATA[
<iq from='juliet@capulet.lit/balcony' to='romeo@montague.lit/orchard' id='mod1' type='set'>
<jingle xmlns='http://www.xmpp.org/extensions/xep-0166.html#ns'
action='content-modify'
initiator='romeo@montague.lit/orchard'
sid='a73sjjvkla37jfea'>
<content creator='initiator' name='this-is-the-audio-content' profile='UDP/TLS/RTP/AVP'/>
</jingle>
</iq>
]]></example>
<p>Romeo then acknowledges the content-modify request and, if it is acceptable, returns a content-accept:</p>
<example caption="Initiator acknowledges content-modify"><![CDATA[
<iq from='romeo@montague.lit/orchard' to='juliet@capulet.lit/balcony' id='mod1' type='result'/>
]]></example>
<example caption="Initiator accepts content definition"><![CDATA[
<iq from='romeo@montague.lit/orchard' to='juliet@capulet.lit/balcony' id='mod2' type='set'>
<jingle xmlns='http://www.xmpp.org/extensions/xep-0166.html#ns'
action='content-accept'
initiator='romeo@montague.lit/orchard'
sid='a73sjjvkla37jfea'>
<content creator='responder' name='this-is-the-audio-content' profile='UDP/TLS/RTP/AVP'/>
</jingle>
</iq>
]]></example>
<p>The other party then acknowledges the acceptance.</p>
<example caption="Receiver acknowledges content-accept"><![CDATA[
<iq from='juliet@capulet.lit/balcony' to='romeo@montague.lit/orchard' id='mod2' type='result'/>
]]></example>
<p>As in the previous scenario, the parties exchange ICE candidates (see above for examples).</p>
<p>If one of the candidate transports is found to work, the receiver accepts the session.</p>
<example caption="Receiver sends session-accept"><![CDATA[
<iq type='set' from='juliet@capulet.lit/balcony' to='romeo@montague.lit/orchard' id='accept1'>
<jingle xmlns='http://www.xmpp.org/extensions/xep-0166.html#ns'
action='session-accept'
initiator='romeo@montague.lit/orchard'
responder='juliet@capulet.lit/balcony'
sid='a73sjjvkla37jfea'>
<content creator='initiator' name='this-is-the-audio-content' profile='UDP/TLS/RTP/AVP'>
<description xmlns='http://www.xmpp.org/extensions/xep-0167.html#ns'>
<payload-type id='97' name='speex' clockrate='8000'/>
<payload-type id='18' name='G729'/>
<payload-type id='0' name='PCMU' />
<payload-type id='102' name='iLBC'/>
<payload-type id='4' name='G723'/>
<payload-type id='8' name='PCMA'/>
<payload-type id='13' name='CN'/>
</description>
<transport xmlns='http://www.xmpp.org/extensions/xep-0176.html#ns'>
<candidate ip='208.245.212.67' port='9876' generation='0'/>
</transport>
</content>
</jingle>
</iq>
]]></example>
<p>If the payload types and transport candidate can be successfully used by both parties, then the initiator acknowledges the session-accept.</p>
<example caption="Initiator acknowledges session-accept"><![CDATA[
<iq type='result' to='juliet@capulet.lit/balcony' from='romeo@montague.lit/orchard' id='accept1'/>
]]></example>
<p>The parties now begin to exchange media. In this case they would exchange audio using the Speex codec at a clockrate of 8000 since that is the highest-priority codec for the responder (as determined by the XML order of the &PAYLOADTYPE; children).</p>
<p>The parties may continue the session as long as desired.</p>
<p>Eventually, one of the parties terminates the session.</p>
<example caption="Receiver terminates the session"><![CDATA[
<iq from='juliet@capulet.lit/balcony'
id='term1'
to='romeo@montague.lit/orchard'
type='set'>
<jingle xmlns='http://www.xmpp.org/extensions/xep-0166.html#ns'
action='session-terminate'
initiator='romeo@montague.lit/orchard'
reason='Sorry, gotta go!'
sid='a73sjjvkla37jfea'/>
</iq>
]]></example>
<p>The other party then acknowledges termination of the session:</p>
<example caption="Initiator acknowledges termination"><![CDATA[
<iq from='romeo@montague.lit/orchard'
id='term1'
to='juliet@capulet.lit/balcony'
type='result'/>
]]></example>
</section2>
</section1>
<section1 topic='Mapping to Session Description Protocol' anchor='sdp'>
<p>If the payload type is static (payload-type IDs 0 through 95 inclusive), it MUST be mapped to a media field defined in <cite>RFC 4566</cite>. The generic format for the media field is as follows:</p>
<code><![CDATA[
m=<media> <port> <transport> <fmt list>
]]></code>
<p>In the context of Jingle audio sessions, the &lt;media&gt; is "audio", the &lt;port&gt; is the preferred port for such communications (which may be determined dynamically), the &lt;transport&gt; is whatever transport method is negotiated via the Jingle negotiation (e.g., "RTP/AVT"), and the &lt;fmt list&gt; is the payload-type ID.</p>
<p>In the context of Jingle audio sessions, the &lt;media&gt; is "audio", the &lt;port&gt; is the preferred port for such communications (which may be determined dynamically), the &lt;transport&gt; is whatever profile is negotiated via the 'profile' attribute of the &CONTENT; element in the Jingle negotiation (e.g., "RTP/AVT"), and the &lt;fmt list&gt; is the payload-type ID.</p>
<p>For example, consider the following static payload-type:</p>
<example caption="Jingle Format for Static Payload-Type"><![CDATA[
<example caption="Jingle format for static payload-type"><![CDATA[
<payload-type id="13" name="CN"/>
]]></example>
<example caption="SDP Mapping of Static Payload-Type"><![CDATA[
<example caption="SDP mapping of static payload-type"><![CDATA[
m=audio 9999 RTP/AVP 13
]]></example>
<p>If the payload type is dynamic (payload-type IDs 96 through 127 inclusive), it SHOULD be mapped to an SDP media field plus an SDP attribute field named "rtpmap".</p>
<p>For example, consider a payload of 16-bit linear-encoded stereo audio sampled at 16KHz associated with dynamic payload-type 96:</p>
<example caption="Jingle Format for Dynamic Payload-Type"><![CDATA[
<example caption="Jingle format for dynamic payload-type"><![CDATA[
<payload-type id='96' name='speex' clockrate='16000'/>
]]></example>
<example caption="SDP Mapping of Dynamic Payload-Type"><![CDATA[
<example caption="SDP mapping of dynamic payload-type"><![CDATA[
m=audio 9999 RTP/AVP 96
a=rtpmap:96 speex/16000
]]></example>
<p>As noted, if additional parameters are to be specified, they shall be represented as attributes of the &lt;payload-type/&gt; element of the child &lt;parameter/&gt; element, as in the following example.</p>
<example caption="Jingle Format for Dynamic Payload-Type With Parameters"><![CDATA[
<example caption="Jingle format for dynamic payload-type with parameters"><![CDATA[
<payload-type id='96' name='speex' clockrate='16000' ptime='40'>
<parameter name='vbr' value='on'/>
<parameter name='cng' value='on'/>
</payload-type>
]]></example>
<example caption="SDP Mapping of Dynamic Payload-Type With Parameters"><![CDATA[
<example caption="SDP mapping of dynamic payload-type with parameters"><![CDATA[
m=audio 9999 RTP/AVP 96
a=rtpmap:96 speex/16000
a=ptime:40
@ -374,7 +1098,7 @@ a=fmtp:96 vbr=on;cng=on
<p>Note: Because the informational message is sent in an IQ-set, the receiving party MUST return either an IQ-result or an IQ-error (normally only an IQ-result to acknowledge receipt; no error flows are defined or envisioned at this time).</p>
</section2>
<section2 topic='Examples' anchor='info-examples'>
<example caption="Receiver Sends Active Message"><![CDATA[
<example caption="Receiver sends active message"><![CDATA[
<iq from='juliet@capulet.com/balcony'
to='romeo@montague.net/orchard'
id='active1'
@ -387,7 +1111,7 @@ a=fmtp:96 vbr=on;cng=on
</jingle>
</iq>
]]></example>
<example caption="Receiver Sends Hold Message"><![CDATA[
<example caption="Receiver sends hold message"><![CDATA[
<iq from='juliet@capulet.com/balcony'
to='romeo@montague.net/orchard'
id='hold1'
@ -400,7 +1124,7 @@ a=fmtp:96 vbr=on;cng=on
</jingle>
</iq>
]]></example>
<example caption="Receiver Sends Mute Message"><![CDATA[
<example caption="Receiver sends mute message"><![CDATA[
<iq from='juliet@capulet.com/balcony'
to='romeo@montague.net/orchard'
id='mute1'
@ -413,7 +1137,7 @@ a=fmtp:96 vbr=on;cng=on
</jingle>
</iq>
]]></example>
<example caption="Receiver Sends Ringing Message"><![CDATA[
<example caption="Receiver sends ringing message"><![CDATA[
<iq from='juliet@capulet.com/balcony'
to='romeo@montague.net/orchard'
id='ringing1'
@ -430,10 +1154,10 @@ a=fmtp:96 vbr=on;cng=on
</section1>
<section1 topic='Error Handling' anchor='errors'>
<p>The Jingle Audio-specific error conditions are as follows:</p>
<p>The Jingle-Audio-specific error conditions are as follows:</p>
<table caption='Other Error Conditions'>
<tr>
<th>Jingle Condition</th>
<th>Jingle Audio Condition</th>
<th>XMPP Condition</th>
<th>Description</th>
</tr>
@ -447,7 +1171,7 @@ a=fmtp:96 vbr=on;cng=on
<section1 topic='Determining Support' anchor='support'>
<p>If an entity supports Jingle audio exchanges via RTP, it MUST advertise that fact by returning a feature of "http://www.xmpp.org/extensions/xep-0167.html#ns" &NSNOTE; in response to &xep0030; information requests.</p>
<example caption="Service Discovery Information Request"><![CDATA[
<example caption="Service discovery information request"><![CDATA[
<iq from='romeo@montague.net/orchard'
id='disco1'
to='juliet@capulet.com/balcony'
@ -455,7 +1179,7 @@ a=fmtp:96 vbr=on;cng=on
<query xmlns='http://jabber.org/protocol/disco#info'/>
</iq>
]]></example>
<example caption="Service Discovery Information Response"><![CDATA[
<example caption="Service discovery information response"><![CDATA[
<iq from='juliet@capulet.com/balcony'
id='disco1'
to='romeo@montague.net/orchard'
@ -478,12 +1202,12 @@ a=fmtp:96 vbr=on;cng=on
<p>If it is necessary to send Dual Tone Multi-Frequency (DTMF) tones, it is REQUIRED to use the XML format specified &xep0181;.</p>
</section2>
<section2 topic='When to Listen' anchor='impl-listen'>
<p>When the Jingle Audio content is accepted via a 'content-accept' action, both initiator and responder SHOULD start listening for audio as defined by the negotiated transport method and audio description. For interoperability with telephony systems, each entity SHOULD both play any audio received and send a ringing tone at this time (i.e., before the receiver sends a 'session-accept' action).</p>
<p>When the Jingle Audio content is accepted via a 'content-accept' action, both initiator and responder SHOULD start listening for audio as defined by the negotiated transport method and audio application format. For interoperability with telephony systems, each entity SHOULD both play any audio received and send a ringing tone at this time (i.e., before the receiver sends a 'session-accept' action).</p>
</section2>
</section1>
<section1 topic='Security Considerations' anchor='security'>
<p>In order to secure the data stream, implementations SHOULD use encryption methods appropriate to the transport method and media being exchanged; for example, in the case of UDP, that would include Datagram Transport Layer Security (DTLS) as specified in &rfc4347;. &sdpdtls; defines such methods for the Session Description Protocol; the relevant RTP profile (e.g., "UDP/TLS/RTP/AVP" for transporting the RTP stream over DTLS with UDP) shall be specified as the value of the &CONTENT; element's 'profile' attribute.</p>
<p>In order to secure the data stream, implementations SHOULD use encryption methods appropriate to the transport method and media being exchanged; for example, in the case of UDP, that would include Datagram Transport Layer Security (DTLS) as specified in &rfc4347;. <cite>draft-fishl-mmusic-sdp-dtls</cite> defines such methods for the Session Description Protocol; the relevant RTP profile (e.g., "UDP/TLS/RTP/AVP" for transporting the RTP stream over DTLS with UDP) shall be specified as the value of the &CONTENT; element's 'profile' attribute.</p>
</section1>
<section1 topic='IANA Considerations' anchor='iana'>
@ -494,21 +1218,21 @@ a=fmtp:96 vbr=on;cng=on
<section2 topic='Protocol Namespaces' anchor='ns'>
<p>Until this specification advances to a status of Draft, its associated namespaces shall be "http://www.xmpp.org/extensions/xep-0167.html#ns" and "http://www.xmpp.org/extensions/xep-0167.html#ns-info"; upon advancement of this specification, the &REGISTRAR; shall issue permanent namespaces in accordance with the process defined in Section 4 of &xep0053;.</p>
</section2>
<section2 topic='Jingle Content Description Formats' anchor='registrar-content'>
<p>The XMPP Registrar shall include "audio-rtp" in its registry of Jingle content description formats. The registry submission is as follows:</p>
<section2 topic='Jingle Application Formats' anchor='registrar-content'>
<p>The XMPP Registrar shall include "audio-rtp" in its registry of Jingle application formats. The registry submission is as follows:</p>
<code><![CDATA[
<content>
<application>
<name>audio-rtp</name>
<desc>Jingle sessions that support audio exchange via the Real-time Transport Protocol</desc>
<transport>lossy</transport>
<doc>XEP-0167</doc>
</content>
</application>
]]></code>
</section2>
</section1>
<section1 topic='XML Schemas' anchor='schema'>
<section2 topic='Content Description Format' anchor='schema-content'>
<section2 topic='Application Format' anchor='schema-content'>
<code><![CDATA[
<?xml version='1.0' encoding='UTF-8'?>