shithub: opus

--- a/doc/draft-ietf-payload-rtp-opus.xml

+++ b/doc/draft-ietf-payload-rtp-opus.xml

@@ -8,17 +8,20 @@

 <!ENTITY rfc6838 PUBLIC '' 'http://xml.resource.org/public/rfc/bibxml/reference.RFC.6838.xml'>

 <!ENTITY rfc4855 PUBLIC '' 'http://xml.resource.org/public/rfc/bibxml/reference.RFC.4855.xml'>

 <!ENTITY rfc4566 PUBLIC '' 'http://xml.resource.org/public/rfc/bibxml/reference.RFC.4566.xml'>

+<!ENTITY rfc4585 PUBLIC '' 'http://xml.resource.org/public/rfc/bibxml/reference.RFC.4585.xml'>

 <!ENTITY rfc3264 PUBLIC '' 'http://xml.resource.org/public/rfc/bibxml/reference.RFC.3264.xml'>

 <!ENTITY rfc2974 PUBLIC '' 'http://xml.resource.org/public/rfc/bibxml/reference.RFC.2974.xml'>

 <!ENTITY rfc2326 PUBLIC '' 'http://xml.resource.org/public/rfc/bibxml/reference.RFC.2326.xml'>

 <!ENTITY rfc3555 PUBLIC '' 'http://xml.resource.org/public/rfc/bibxml/reference.RFC.3555.xml'>

+<!ENTITY rfc5124 PUBLIC '' 'http://xml.resource.org/public/rfc/bibxml/reference.RFC.5124.xml'>

 <!ENTITY rfc5576 PUBLIC '' 'http://xml.resource.org/public/rfc/bibxml/reference.RFC.5576.xml'>

 <!ENTITY rfc6562 PUBLIC '' 'http://xml.resource.org/public/rfc/bibxml/reference.RFC.6562.xml'>

 <!ENTITY rfc6716 PUBLIC '' 'http://xml.resource.org/public/rfc/bibxml/reference.RFC.6716.xml'>

+<!ENTITY rfc7202 PUBLIC '' 'http://xml.resource.org/public/rfc/bibxml/reference.RFC.7202.xml'>

 <!ENTITY nbsp "&#160;">

]>

-  <rfc category="std" ipr="trust200902" docName="draft-ietf-payload-rtp-opus-08">

+  <rfc category="std" ipr="trust200902" docName="draft-ietf-payload-rtp-opus-09">

 <?xml-stylesheet type='text/xsl' href='rfc2629.xslt' ?>

 <?rfc strict="yes" ?>

@@ -71,7 +74,7 @@

       </address>

     </author>

-    <date day='6' month='February' year='2015' />

+    <date day='10' month='April' year='2015' />

     <abstract>

<t>

@@ -78,7 +81,8 @@

         This document defines the Real-time Transport Protocol (RTP) payload

         format for packetization of Opus encoded

         speech and audio data necessary to integrate the codec in the

-        most compatible way. Further, it describes media type registrations

+        most compatible way. It also provides an applicability statement

+        for the use of Opus over RTP. Further, it describes media type registrations

         for the RTP payload format.

       </t>

     </abstract>

@@ -100,7 +104,9 @@

         <xref target="RFC3550"/> payload format for packetization

         of Opus encoded speech and audio data necessary to

         integrate Opus in the

-        most compatible way. Further, it describes media type registrations for

+        most compatible way. It also provides an applicability statement

+        for the use of Opus over RTP.

+        Further, it describes media type registrations for

         the RTP payload format.

       </t>

     </section>

@@ -179,7 +185,7 @@

<t>

         Opus is highly scalable in terms of audio

         bandwidth, bitrate, and complexity. Further, Opus allows

-        transmitting stereo signals.

+        transmitting stereo signals with in-band signaling in the bit-stream.

       </t>

       <section title='Network Bandwidth'>

@@ -268,7 +274,7 @@

             DTX can be used with both variable and constant bitrate.

             It will have a slightly lower speech or audio

             quality than continuous transmission. Therefore, using continuous

-            transmission is RECOMMENDED unless restraints on available network bandwidth

+            transmission is RECOMMENDED unless constraints on available network bandwidth

             are severe.

           </t>

@@ -327,7 +333,7 @@

<t>

           Opus allows for transmission of stereo audio signals. This operation

-          is signaled in-band in the Opus payload and no special arrangement

+          is signaled in-band in the Opus bit-stream and no special arrangement

           is needed in the payload format. An

           Opus decoder is capable of handling a stereo encoding, but an

           application might only be capable of consuming a single audio

@@ -368,7 +374,7 @@

         Opus decoder for decoding, and MUST discard the others.</t>

         <t>Opus supports 5 different audio bandwidths, which can be adjusted during

-        a call.

+        a stream.

         The RTP timestamp is incremented with a 48000 Hz clock rate

         for all modes of Opus and all sampling rates.

         The unit

@@ -463,8 +469,14 @@

       time increases latency and loss sensitivity, so it ought to be used with

       care.</t>

-      <t>It is RECOMMENDED that senders of Opus encoded data apply congestion

-      control.</t>

+      <t>Since UDP does not provide congestion control, applications that use

+      RTP over UDP SHOULD implement their own congestion control above the

+      UDP layer. <xref target="draft-ietf-rmcat-app-interaction-01"/> describes the

+      interactions and conceptual interfaces necessary between the application

+      components that relate to congestion control, including the RTP layer,

+      the higher-level media codec control layer, and the lower-level

+      transport interface, as well as components dedicated to congestion

+      control functions.</t>

     </section>

     <section title='IANA Considerations'>

@@ -876,6 +888,26 @@

       specification <xref target="RFC3550"/> and any profile from,

       e.g., <xref target="RFC3711"/> or <xref target="RFC3551"/>.</t>

+      <t>Use of variable bitrate (VBR) is subject to the security considerations in

+      <xref target="RFC6562"/>.</t>

+      <t>RTP packets using the payload format defined in this specification

+      are subject to the security considerations discussed in the RTP

+      specification <xref target="RFC3550"/>, and in any applicable RTP profile such as

+      RTP/AVP <xref target="RFC3551"/>, RTP/AVPF <xref target="RFC4585"/>,

+      RTP/SAVP <xref target="RFC3711"/> or RTP/SAVPF <xref target="RFC5124"/>.

+      However, as "Securing the RTP Protocol Framework:

+      Why RTP Does Not Mandate a Single Media Security Solution"

+      <xref target="RFC7202"/> discusses it is not an RTP payload

+      formats responsibility to discuss or mandate what solutions are used

+      to meet the basic security goals like confidentiality, integrity and

+      source authenticity for RTP in general.  This responsibility lays on

+      anyone using RTP in an application.  They can find guidance on

+      available security mechanisms and important considerations in Options

+      for Securing RTP Sessions [I-D.ietf-avtcore-rtp-security-options].

+      Applications SHOULD use one or more appropriate strong security

+      mechanisms.</t>

       <t>This payload format transports Opus encoded speech or audio data.

       Hence, security issues include confidentiality, integrity protection, and

       authentication of the speech or audio itself. Opus does not provide

@@ -915,6 +947,30 @@

     <references title="Informative References">

       &rfc2974;

+      &rfc4585;

+      &rfc5124;

+      &rfc7202;

+      <reference anchor='draft-ietf-rmcat-app-interaction-01' target='http://tools.ietf.org/html/draft-ietf-rmcat-app-interaction-01'>

+        <front>

+          <title>RTP Application Interaction with Congestion Control</title>

+          <author initials='M.' surname='Zanaty' fullname='M. Zanaty'>

+          <organization /></author>

+          <author initials='V.' surname='Singh' fullname='V. Singh'>

+          <organization /></author>

+          <author initials='S.' surname='Nandakumar' fullname='S. Nandakumar'>

+          <organization /></author>

+          <author initials='Z.' surname='Sarker' fullname='Z. Sarker'>

+          <organization /></author>

+          <date year='2014' month='October' />

+          <abstract>

+            <t></t>

+          </abstract></front>

+        <seriesInfo name='Internet-Draft' value='draft-ietf-rmcat-app-interaction-01' />

+        <format type='TXT' target='http://tools.ietf.org/html/draft-ietf-rmcat-app-interaction-01' />

+      </reference>

     </references>

   </back>