draft-ietf-mmusic-mux-exclusive-03.txt   draft-ietf-mmusic-mux-exclusive-04.txt 
Network Working Group C. Holmberg Network Working Group C. Holmberg
Internet-Draft Ericsson Internet-Draft Ericsson
Intended status: Standards Track February 15, 2016 Updates: 5761 (if approved) April 15, 2016
Expires: August 18, 2016 Intended status: Standards Track
Expires: October 17, 2016
Indicating Exclusive Support of RTP/RTCP Multiplexing using SDP Indicating Exclusive Support of RTP/RTCP Multiplexing using SDP
draft-ietf-mmusic-mux-exclusive-03 draft-ietf-mmusic-mux-exclusive-04
Abstract Abstract
This document defines a new SDP media-level attribute, 'rtcp-mux- This document defines a new SDP media-level attribute, 'rtcp-mux-
exclusive', that can be used by an endpoint to indicate exclusive only', that can be used by an endpoint to indicate exclusive support
support of RTP/RTCP multiplexing. of RTP/RTCP multiplexing. The document also updates RFC 5761, by
clarifying that an offerer can use a mechanism to indicate that it is
not able to send and receive RTCP on separate ports.
Status of This Memo Status of This Memo
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Conventions . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Conventions . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. SDP rtcp-mux-exclusive Attribute . . . . . . . . . . . . . . 3 3. SDP rtcp-mux-only Attribute . . . . . . . . . . . . . . . . . 3
4. SDP Offer/Answer Procedures . . . . . . . . . . . . . . . . . 4 4. SDP Offer/Answer Procedures . . . . . . . . . . . . . . . . . 4
4.1. General . . . . . . . . . . . . . . . . . . . . . . . . . 4 4.1. General . . . . . . . . . . . . . . . . . . . . . . . . . 4
4.2. Generating the Initial SDP Offer . . . . . . . . . . . . 4 4.2. Generating the Initial SDP Offer . . . . . . . . . . . . 4
4.3. Generating the Answer . . . . . . . . . . . . . . . . . . 4 4.3. Generating the Answer . . . . . . . . . . . . . . . . . . 5
4.4. Offerer Processing of the SDP Answer . . . . . . . . . . 5 4.4. Offerer Processing of the SDP Answer . . . . . . . . . . 5
4.5. Modifying the Session . . . . . . . . . . . . . . . . . . 5 4.5. Modifying the Session . . . . . . . . . . . . . . . . . . 5
5. ICE Considerations . . . . . . . . . . . . . . . . . . . . . 6 5. Update to RFC 5761 . . . . . . . . . . . . . . . . . . . . . 6
6. Security Considerations . . . . . . . . . . . . . . . . . . . 6 5.1. General . . . . . . . . . . . . . . . . . . . . . . . . . 6
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 6 5.2. Update to 4th paragraph of section 5.1.1 . . . . . . . . 6
8. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 6 5.3. Update to 2nd paragraph of section 5.1.3 . . . . . . . . 7
9. Change Log . . . . . . . . . . . . . . . . . . . . . . . . . 7 6. ICE Considerations . . . . . . . . . . . . . . . . . . . . . 8
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 7 7. Security Considerations . . . . . . . . . . . . . . . . . . . 8
10.1. Normative References . . . . . . . . . . . . . . . . . . 7 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8
10.2. Informative References . . . . . . . . . . . . . . . . . 8 9. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 9
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 8 10. Change Log . . . . . . . . . . . . . . . . . . . . . . . . . 9
11. References . . . . . . . . . . . . . . . . . . . . . . . . . 10
11.1. Normative References . . . . . . . . . . . . . . . . . . 10
11.2. Informative References . . . . . . . . . . . . . . . . . 11
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 11
1. Introduction 1. Introduction
[RFC5761] defines how to multiplex RTP and RTCP on a single IP [RFC5761] defines how to multiplex RTP and RTCP on a single IP
address and port, referred to as RTP/RTCP multiplexing. [RFC5761] address and port, referred to as RTP/RTCP multiplexing. [RFC5761]
also defines an Session Description Protocol (SDP) [RFC4566] also defines an Session Description Protocol (SDP) [RFC4566]
attribute, 'rtcp-mux' that can be used by entities to indicate attribute, 'rtcp-mux' that can be used by entities to indicate
support, and negotiate usage of, RTP/RTCP multiplexing. support, and negotiate usage of, RTP/RTCP multiplexing.
As defined in [RFC5761], if the peer endpoint does not support RTP/ As defined in [RFC5761], if the peer endpoint does not support RTP/
RTCP multiplexing, there must be a fallback to usage of separate RTCP multiplexing, both endpoints should use separate ports for
ports for RTP and RTCP. sending and receiving of RTCP (referred to as fallback to usage of
separate ports for RTP and RTCP).
The RTCWEB WG has defined that support of the fallback mentioned Some newer applications that do not require backward compatibility
above is optional. Therefore, there is a need for a mechanism that with peers that cannot multiplex RTCP might choose to not implement
allows an endpoint to indicate exclusive support of RTP/RTCP separation of RTP and RTCP. For those applications, this document
multiplexing, meaning that endpoint only supports RTP/RTCP defines an SDP attribute to signal intent to require multiplexing.
multiplexing and is not able to fallback to usage of separate ports
for RTP and RTCP.
This document defines a new SDP media-level attribute, 'rtcp-mux- This document defines a new SDP media-level attribute, 'rtcp-mux-
exclusive', that can be used to indicate exclusive support of RTP/ only', that can be used by an endpoint to indicate exclusive support
RTCP multiplexing. of RTP/RTCP multiplexing. The document also updates RFC 5761, by
clarifying that an offerer can use a mechanism to indicate that it is
not able to send and receive RTCP on separate ports.
The document also describes the Interactive Connectivity The document also describes the Interactive Connectivity
Establishment (ICE) [I-D.ietf-ice-rfc5245bis] considerations when Establishment (ICE) [I-D.ietf-ice-rfc5245bis] considerations when
indicating exclusive support of RTP/RTCP multiplexing. indicating exclusive support of RTP/RTCP multiplexing.
2. Conventions 2. Conventions
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119]. document are to be interpreted as described in [RFC2119].
3. SDP rtcp-mux-exclusive Attribute 3. SDP rtcp-mux-only Attribute
This section defines a new SDP media-level attribute, 'rtcp-mux- This section defines a new SDP media-level attribute, 'rtcp-mux-
exclusive'. only'.
Name: rtcp-mux-exclusive Name: rtcp-mux-only
Value: N/A Value: N/A
Usage Level: media Usage Level: media
Charset Dependent: no Charset Dependent: no
Syntax: Syntax:
rtcp-mux-exclusive rtcp-mux-only
Example: Example:
a=rtcp-mux-exclusive a=rtcp-mux-only
In an SDP offer, the offerer uses the SDP 'rtcp-mux-exclusive' In an SDP offer, the offerer uses the SDP 'rtcp-mux-only' attribute
attribute to indicate exclusive support of RTP/RTCP multiplexing for to indicate exclusive support of RTP/RTCP multiplexing for the RTP-
based media associated with the SDP media description ("m=" line).
In an SDP answer, the 'rtcp-mux-only' attribute indicates that the
answerer supports, and accepts usage of, RTP/RTCP multiplexing for
the RTP-based media associated with the SDP media description ("m=" the RTP-based media associated with the SDP media description ("m="
line). line).
In an SDP answer, the 'rtcp-mux-exclusive' attribute indicates that The usage of the SDP 'rtcp-mux-only' attribute is only defined for
the answerer supports, and accepts usage of, RTP/RTCP multiplexing RTP-based media.
for the RTP-based media associated with the SDP media description
("m=" line).
The usage of the SDP 'rtcp-mux-exclusive' attribute is only defined
for RTP-based media.
The mux category [I-D.ietf-mmusic-sdp-mux-attributes] for the 'rtcp- The mux category [I-D.ietf-mmusic-sdp-mux-attributes] for the 'rtcp-
mux-exclusive' attribute is 'NORMAL', which means that the attribute mux-only' attribute is 'NORMAL', which means that the attribute can
can be associated with an individual media description, even if the be associated with an individual media description, even if the media
media description is multiplexed with other media descriptions description is multiplexed with other media descriptions
[I-D.ietf-mmusic-sdp-bundle-negotiation] with which the attribute is [I-D.ietf-mmusic-sdp-bundle-negotiation] with which the attribute is
not associated. not associated.
The 'rtcp-mux-exclusive' attribute applies to the whole associated The 'rtcp-mux-only' attribute applies to the whole associated media
media description. The attribute MUST NOT be defined per source description. The attribute MUST NOT be defined per source (using the
(using the SDP 'ssrc' attribute [RFC5576]). SDP 'ssrc' attribute [RFC5576]).
The SDP offer/answer [RFC3264] procedures associated with the The SDP offer/answer [RFC3264] procedures associated with the
attribute are defined in Section 4 attribute are defined in Section 4
4. SDP Offer/Answer Procedures 4. SDP Offer/Answer Procedures
4.1. General 4.1. General
This section defines the SDP offer/answer [RFC3264] procedures for This section defines the SDP offer/answer [RFC3264] procedures for
indicating exclusive support of, and negotiating usage of, RTP/RTCP indicating exclusive support of, and negotiating usage of, RTP/RTCP
multiplexing. multiplexing.
The procedures in this section apply to individual RTP-based SDP The procedures in this section apply to individual RTP-based SDP
media descriptions ("m=" lines). media descriptions ("m=" lines).
4.2. Generating the Initial SDP Offer 4.2. Generating the Initial SDP Offer
When an offerer sends the initial offer, if the offerer wants to When an offerer sends the initial offer, if the offerer wants to
indicate exclusive RTP/RTCP multiplexing for RTP-based media, the indicate exclusive RTP/RTCP multiplexing for RTP-based media, the
offerer MUST associate an SDP 'rtcp-mux-exclusive' attribute with the offerer MUST associate an SDP 'rtcp-mux-only' attribute with the
associated SDP media description ("m=" line). associated SDP media description ("m=" line).
In addition, if the offerer associates an SDP 'rtcp-mux-exclusive' In addition, if the offerer associates an SDP 'rtcp-mux-only'
attribute with an SDP media description ("m=" line), the offerer MUST attribute with an SDP media description ("m=" line), the offerer MAY
also associate an SDP 'rtcp-mux' attribute with the same SDP media also associate an SDP 'rtcp-mux' attribute with the same SDP media
description ("m=" line), following the procedures in [RFC5761]. description ("m=" line), following the procedures in [RFC5761].
If the offerer associates an SDP 'rtcp' attribute [RFC3605] with an If the offerer associates an SDP 'rtcp' attribute [RFC3605] with an
SDP media description ("m=" line), and if the offerer also associates SDP media description ("m=" line), and if the offerer also associates
an SDP 'rtcp-mux-exclusive' attribute with the same SDP media an SDP 'rtcp-mux-only' attribute with the same SDP media description
description ("m=" line), the address and port values of the SDP ("m=" line), the address and port values of the SDP 'rtcp' attribute
'rtcp' attribute MUST match the corresponding values for RTP. MUST match the corresponding values for RTP.
NOTE: This specification does not mandate the usage of the SDP 'rtcp' NOTE: This specification does not mandate the usage of the SDP 'rtcp'
attribute for RTP/RTCP multiplexing. attribute for RTP/RTCP multiplexing.
4.3. Generating the Answer 4.3. Generating the Answer
When an answerer receives an offer that contains an SDP 'rtcp-mux- When an answerer receives an offer that contains an SDP 'rtcp-mux-
exclusive' attribute, associated with an RTP-based SDP media only' attribute, associated with an RTP-based SDP media description
description ("m=" line), if the answerer accepts the usage of RTP/ ("m=" line), if the answerer accepts the usage of RTP/RTCP
RTCP multiplexing, the answerer MUST associate an SDP 'rtcp-mux- multiplexing, the answerer MUST associate an SDP 'rtcp-mux-only'
exclusive' attribute with the corresponding SDP media description attribute with the corresponding SDP media description ("m=") in the
("m=") in the associated answer. If the answerer does not accept the associated answer. If the answerer does not accept the usage of RTP/
usage of RTP/RTCP multiplexing, the answerer MUST either reject the RTCP multiplexing, the answerer MUST either reject the SDP media
SDP media description ("m=") by setting the port value to zero in the description ("m=") by setting the port value to zero in the
associated answer, or reject the whole offer, following the associated answer, or reject the whole offer, following the
procedures in [RFC3264]. procedures in [RFC3264].
In addition, if the answerer associates an SDP 'rtcp-mux-exclusive' In addition, if the answerer associates an SDP 'rtcp-mux-only'
attribute with an SDP media description ("m=" line) in the answer, attribute with an SDP media description ("m=" line) in the answer,
the answerer MUST also associate an SDP 'rtcp-mux' attribute with the and if the corresponding "m=" line in the associated offer contained
same SDP media description ("m=" line), following the procedures in an SDP 'rtcp-mux' attribute, the answerer MUST in addition associate
[RFC5761]. an SDP 'rtcp-mux' attribute with the same "m=" line, following the
procedures in [RFC5761].
4.4. Offerer Processing of the SDP Answer 4.4. Offerer Processing of the SDP Answer
If an offerer associated an SDP 'rtcp-mux-exclusive' attribute with If an offerer associated an SDP 'rtcp-mux-only' attribute with an
an RTP-based SDP media description ("m=" line) in an offer, and if RTP-based SDP media description ("m=" line) in an offer, and if the
the corresponding SDP media description ("m=" line) in the associated corresponding SDP media description ("m=" line) in the associated
answer contains an SDP 'rtcp-mux-exclusive' attribute, and/or an SDP answer contains an SDP 'rtcp-mux-only' attribute, and/or an SDP
'rtcp-mux' attribute, the offerer MUST apply the RTP/RTCP 'rtcp-mux' attribute, the offerer MUST apply the RTP/RTCP
multiplexing procedures [RFC5761] to the associated RTP-based media. multiplexing procedures [RFC5761] to the associated RTP-based media.
If the corresponding SDP media description ("m=" line) in the If the corresponding SDP media description ("m=" line) in the
associated answer does not contain an SDP 'rtcp-mux-exclusive' associated answer does not contain an SDP 'rtcp-mux-only' attribute,
attribute, nor an SDP 'rtcp-mux' attribute, the offerer MUST either nor an SDP 'rtcp-mux' attribute, the offerer MUST either take
take appropriate actions in order to disable the associated RTP-based appropriate actions in order to disable the associated RTP-based
media, or send a new offer without associating an SDP 'rtcp-mux- media, or send a new offer without associating an SDP 'rtcp-mux-only'
exclusive' attribute with the SDP media description ("m=" line). attribute with the SDP media description ("m=" line).
NOTE: This document does not mandate specific actions on how to NOTE: This document does not mandate specific actions on how to
terminate the RTP media. The offerer might e.g. send a new offer, terminate the RTP media. The offerer might e.g. send a new offer,
where the port value of the SDP media description is set to zero, in where the port value of the SDP media description is set to zero, in
order to terminate the RTP media. order to terminate the RTP media.
4.5. Modifying the Session 4.5. Modifying the Session
When an offerer sends a subsequent offer, if the offerer and answerer When an offerer sends a subsequent offer, if the offerer and answerer
have previously negotiated usage of RTP/RTCP multiplexing for the have previously negotiated usage of exclusive RTP/RTCP multiplexing
media associated with an RTP-based SDP media description ("m=" line), for the media associated with an RTP-based SDP media description
the offerer SHOULD associate an SDP 'rtcp-mux-exclusive' attribute ("m=" line), the offerer SHOULD associate an SDP 'rtcp-mux-only' with
and an SDP 'rtcp-mux' attribute with the corresponding SDP media the corresponding SDP media description ("m=" line).
description ("m=" line). If the offerer does not associate the
attributes with the corresponding SDP media description ("m=" line) In addition, if the offerer associates an SDP 'rtcp-mux-only'
it is an indication that the offerer no longer wants to use RTP/RTCP attribute with an SDP media description ("m=" line), the offerer MAY
multiplexing, and instead MUST fallback to usage of separate ports also associate an SDP 'rtcp-mux' attribute with the same SDP media
for RTP and RTCP once the offer has been accepted by the answerer. description ("m=" line), following the procedures in [RFC5761].
If the offerer does not associate the attributes with the
corresponding SDP media description ("m=" line) it is an indication
that the offerer no longer wants to use RTP/RTCP multiplexing, and
instead MUST fallback to usage of separate ports for RTP and RTCP
once the offer has been accepted by the answerer.
When an offerer sends a subsequent offer, if the offerer and answerer When an offerer sends a subsequent offer, if the offerer and answerer
have not previously negotiated usage of RTP/RTCP multiplexing for the have not previously negotiated usage of RTP/RTCP multiplexing for the
media associated with an RTP-based SDP media description ("m=" line), media associated with an RTP-based SDP media description ("m=" line),
the offerer MAY indicate exclusive support of RTP/RTCP multiplexing, the offerer MAY indicate exclusive support of RTP/RTCP multiplexing,
following the procedures in Section 4.2. The offerer MUST process following the procedures in Section 4.2. The offerer MUST process
the associated answer following the procedures in Section 4.4. the associated answer following the procedures in Section 4.4.
NOTE: It is RECOMMENDED to not switch between usage of RTP/RTCP NOTE: It is RECOMMENDED to not switch between usage of RTP/RTCP
multiplexing and usage of separate ports for RTP and RTCP in a multiplexing and usage of separate ports for RTP and RTCP in a
subsequent offer, unless there is a use-case that mandates it. subsequent offer, unless there is a use-case that mandates it.
5. ICE Considerations 5. Update to RFC 5761
5.1. General
This section updates sections 5.1.1 and 5.1.3 of RFC 5761, by
clarifying that an offerer can use a mechanism to indicate that it is
not able to send and receive RTCP on separate ports, and that the
offerer shall terminate the affected streams if the answerer does not
indicate support of RTP/RTCP multiplexing. It also clarifies that,
when the offerer is not able to send and receive RTCP on separate
ports, the offerer will not provide an SDP 'candidate' attribute for
RTCP, nor will the offerer provide a fallback port for RTCP (using
the SDP 'rtcp' attribute).
5.2. Update to 4th paragraph of section 5.1.1
OLD TEXT:
If the answer does not contain an "a=rtcp-mux" attribute, the offerer
MUST NOT multiplex RTP and RTCP packets on a single port. Instead,
it should send and receive RTCP on a port allocated according to the
usual port-selection rules (either the port pair, or a signalled port
if the "a=rtcp:" attribute [10] is also included). This will occur
when talking to a peer that does not understand the "a=rtcp-mux"
attribute.
NEW TEXT:
If the answer does not contain an "a=rtcp-mux" attribute, the offerer
MUST NOT multiplex RTP and RTCP packets on a single port. Instead,
it should send and receive RTCP on a port allocated according to the
usual port-selection rules (either the port pair, or a signalled port
if the "a=rtcp:" attribute [10] is also included). This will occur
when talking to a peer that does not understand the "a=rtcp-mux"
attribute. However, if the offerer indicated in the offer that it is
not able to send and receive RTCP on a separate port, the offerer
MUST disable the media streams associated with the attribute. The
mechanism for indicating that the offerer is not able to send and
receive RTCP on a separate port is outside the scope of this
specification.
5.3. Update to 2nd paragraph of section 5.1.3
OLD TEXT:
If it is desired to use both ICE and multiplexed RTP and RTCP, the
initial offer MUST contain an "a=rtcp-mux" attribute to indicate that
RTP and RTCP multiplexing is desired and MUST contain "a=candidate:"
lines for both RTP and RTCP along with an "a=rtcp:" line indicating a
fallback port for RTCP in the case that the answerer does not support
RTP and RTCP multiplexing. This MUST be done for each media where
RTP and RTCP multiplexing is desired.
NEW TEXT:
If it is desired to use both ICE and multiplexed RTP and RTCP, the
initial offer MUST contain an "a=rtcp-mux" attribute to indicate that
RTP and RTCP multiplexing is desired and MUST contain "a=candidate:"
lines for both RTP and RTCP along with an "a=rtcp:" line indicating a
fallback port for RTCP in the case that the answerer does not support
RTP and RTCP multiplexing. This MUST be done for each media where
RTP and RTCP multiplexing is desired. However, if the offerer
indicates in the offer that it is not able to send and receive RTCP
on a separate port, the offerer MUST NOT include "a=candidiate:" lines
for RTCP, and the offerer MUST NOT provide a fallback port for RTCP using
the "a=rtcp:" line.
6. ICE Considerations
As defined in [I-D.ietf-ice-rfc5245bis], if an entity is aware that As defined in [I-D.ietf-ice-rfc5245bis], if an entity is aware that
the remote peer supports, and is willing to use, RTP/RTCP the remote peer supports, and is willing to use, RTP/RTCP
multiplexing, the entity will only provide RTP candidates (component multiplexing, the entity will only provide RTP candidates (component
ID 1). However, only providing RTP candidates does not as such imply ID 1). However, only providing RTP candidates does not as such imply
exclusive support of RTP/RTCP multiplexing. RTCP candidates would exclusive support of RTP/RTCP multiplexing. RTCP candidates would
not be provided also in cases where RTCP is not supported at all. not be provided also in cases where RTCP is not supported at all.
Therefore, additional information is needed in order to indicate Therefore, additional information is needed in order to indicate
support of exclusive RTP/RTCP multiplexing. This document defines support of exclusive RTP/RTCP multiplexing. This document defines
such mechanism using the SDP 'rtcp-mux-exclusive' attributes. such mechanism using the SDP 'rtcp-mux-only' attributes.
6. Security Considerations 7. Security Considerations
This document does not introduce new security considerations in This document does not introduce new security considerations in
additions to those specified in [RFC3605] and [RFC5761]. additions to those specified in [RFC3605] and [RFC5761].
7. IANA Considerations 8. IANA Considerations
This document updates the "Session Description Protocol Parameters" This document updates the "Session Description Protocol Parameters"
registry as specified in Section 8.2.2 of [RFC4566]. Specifically, registry as specified in Section 8.2.2 of [RFC4566]. Specifically,
it adds the SDP 'rtcp-mux-exclusive' attribute to the table for SDP it adds the SDP 'rtcp-mux-only' attribute to the table for SDP media
media level attributes. level attributes.
Attribute name: rtcp-mux-exclusive Attribute name: rtcp-mux-only
Type of attribute: media-level Type of attribute: media-level
Subject to charset: no Subject to charset: no
Purpose: Indicate exclusive support of RTP/RTCP multiplexing Purpose: Indicate exclusive support of RTP/RTCP multiplexing
Appropriate Values: Appropriate Values:
Contact name: Christer Holmberg Contact name: Christer Holmberg
Category: NORMAL Category: NORMAL
8. Acknowledgments 9. Acknowledgments
Thanks to Roman Shpount, Paul Kyzivat, Ari Keranen, Bo Burman and Thanks to Roman Shpount, Paul Kyzivat, Ari Keranen, Bo Burman, Tomas
Tomas Frankkila for their comments and input on the draft. Frankkila and Martin Thomson for their comments and input on the
document.
9. Change Log 10. Change Log
[RFC EDITOR NOTE: Please remove this section when publishing] [RFC EDITOR NOTE: Please remove this section when publishing]
Changes from draft-ietf-mmusic-rtcp-mux-exclusive-03
o Editorial changes based on comments from Martin Thomson.
o Change of attribute name.
o RFC 5761 updates added.
Changes from draft-ietf-mmusic-rtcp-mux-exclusive-02 Changes from draft-ietf-mmusic-rtcp-mux-exclusive-02
o Minor editorial fix. o Minor editorial fix.
Changes from draft-ietf-mmusic-rtcp-mux-exclusive-01 Changes from draft-ietf-mmusic-rtcp-mux-exclusive-01
o Mux category and source-specific applicability added. o Mux category and source-specific applicability added.
Changes from draft-ietf-mmusic-rtcp-mux-exclusive-00 Changes from draft-ietf-mmusic-rtcp-mux-exclusive-00
skipping to change at page 7, line 44 skipping to change at page 10, line 24
o Clarified that the SDP rtcp attribute may contain the optional IP o Clarified that the SDP rtcp attribute may contain the optional IP
address part. address part.
Changes from draft-holmberg-mmusic-rtcp-mux-exclusive-00 Changes from draft-holmberg-mmusic-rtcp-mux-exclusive-00
o Additional updates to Section 5.1.1 of RFC 5761. o Additional updates to Section 5.1.1 of RFC 5761.
o ICE considerations added. o ICE considerations added.
10. References 11. References
10.1. Normative References 11.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997, DOI 10.17487/RFC2119, March 1997,
<http://www.rfc-editor.org/info/rfc2119>. <http://www.rfc-editor.org/info/rfc2119>.
[RFC3264] Rosenberg, J. and H. Schulzrinne, "An Offer/Answer Model [RFC3264] Rosenberg, J. and H. Schulzrinne, "An Offer/Answer Model
with Session Description Protocol (SDP)", RFC 3264, with Session Description Protocol (SDP)", RFC 3264,
DOI 10.17487/RFC3264, June 2002, DOI 10.17487/RFC3264, June 2002,
<http://www.rfc-editor.org/info/rfc3264>. <http://www.rfc-editor.org/info/rfc3264>.
skipping to change at page 8, line 25 skipping to change at page 11, line 5
Control Packets on a Single Port", RFC 5761, Control Packets on a Single Port", RFC 5761,
DOI 10.17487/RFC5761, April 2010, DOI 10.17487/RFC5761, April 2010,
<http://www.rfc-editor.org/info/rfc5761>. <http://www.rfc-editor.org/info/rfc5761>.
[I-D.ietf-ice-rfc5245bis] [I-D.ietf-ice-rfc5245bis]
Keranen, A. and J. Rosenberg, "Interactive Connectivity Keranen, A. and J. Rosenberg, "Interactive Connectivity
Establishment (ICE): A Protocol for Network Address Establishment (ICE): A Protocol for Network Address
Translator (NAT) Traversal", draft-ietf-ice-rfc5245bis-00 Translator (NAT) Traversal", draft-ietf-ice-rfc5245bis-00
(work in progress), October 2015. (work in progress), October 2015.
10.2. Informative References 11.2. Informative References
[RFC3605] Huitema, C., "Real Time Control Protocol (RTCP) attribute [RFC3605] Huitema, C., "Real Time Control Protocol (RTCP) attribute
in Session Description Protocol (SDP)", RFC 3605, in Session Description Protocol (SDP)", RFC 3605,
DOI 10.17487/RFC3605, October 2003, DOI 10.17487/RFC3605, October 2003,
<http://www.rfc-editor.org/info/rfc3605>. <http://www.rfc-editor.org/info/rfc3605>.
[RFC5576] Lennox, J., Ott, J., and T. Schierl, "Source-Specific [RFC5576] Lennox, J., Ott, J., and T. Schierl, "Source-Specific
Media Attributes in the Session Description Protocol Media Attributes in the Session Description Protocol
(SDP)", RFC 5576, DOI 10.17487/RFC5576, June 2009, (SDP)", RFC 5576, DOI 10.17487/RFC5576, June 2009,
<http://www.rfc-editor.org/info/rfc5576>. <http://www.rfc-editor.org/info/rfc5576>.
 End of changes. 41 change blocks. 
96 lines changed or deleted 184 lines changed or added

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