draft-ietf-xrblock-rtcp-xr-delay-12.txt   rfc6843.txt 
Audio/Video Transport Working Group A. Clark Internet Engineering Task Force (IETF) A. Clark
Internet-Draft Telchemy Request for Comments: 6843 Telchemy
Intended status: Standards Track K. Gross Category: Standards Track K. Gross
Expires: May 23, 2013 AVA Networks ISSN: 2070-1721 AVA Networks
Q. Wu Q. Wu
Huawei Huawei
November 19, 2012 January 2013
RTP Control Protocol (RTCP) Extended Report (XR) Block for Delay metric RTP Control Protocol (RTCP) Extended Report (XR)
Reporting Block for Delay Metric Reporting
draft-ietf-xrblock-rtcp-xr-delay-12.txt
Abstract Abstract
This document defines an RTP Control Protocol(RTCP) Extended Report This document defines an RTP Control Protocol (RTCP) Extended Report
(XR) Block that allows the reporting of Delay metrics for use in a (XR) block that allows the reporting of delay metrics for use in a
range of Real-time Transport Protocol applications. range of Real-time Transport Protocol (RTP) applications.
Status of this Memo
This Internet-Draft is submitted in full conformance with the Status of This Memo
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering This is an Internet Standards Track document.
Task Force (IETF). Note that other groups may also distribute
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Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months This document is a product of the Internet Engineering Task Force
and may be updated, replaced, or obsoleted by other documents at any (IETF). It represents the consensus of the IETF community. It has
time. It is inappropriate to use Internet-Drafts as reference received public review and has been approved for publication by the
material or to cite them other than as "work in progress." Internet Engineering Steering Group (IESG). Further information on
Internet Standards is available in Section 2 of RFC 5741.
This Internet-Draft will expire on May 23, 2013. Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
http://www.rfc-editor.org/info/rfc6843.
Copyright Notice Copyright Notice
Copyright (c) 2012 IETF Trust and the persons identified as the Copyright (c) 2013 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
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described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction ....................................................2
1.1. Packet Delay Metrics Block . . . . . . . . . . . . . . . . 3 1.1. Packet Delay Metrics Block .................................2
1.2. RTCP and RTCP XR Reports . . . . . . . . . . . . . . . . . 3 1.2. RTCP and RTCP XR Reports ...................................2
1.3. Performance Metrics Framework . . . . . . . . . . . . . . 3 1.3. Performance Metrics Framework ..............................3
1.4. Applicability . . . . . . . . . . . . . . . . . . . . . . 3 1.4. Applicability ..............................................3
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4 2. Terminology .....................................................3
2.1. Standards Language . . . . . . . . . . . . . . . . . . . . 4 2.1. Standards Language .........................................3
3. Delay Block . . . . . . . . . . . . . . . . . . . . . . . . . 5 3. Delay Block .....................................................3
3.1. Report Block Structure . . . . . . . . . . . . . . . . . . 5 3.1. Report Block Structure .....................................4
3.2. Definition of Fields in Delay Metrics Report Block . . . . 5 3.2. Definition of Fields in Delay Metrics Report Block .........4
4. SDP Signaling . . . . . . . . . . . . . . . . . . . . . . . . 9 4. SDP Signaling ...................................................6
4.1. SDP rtcp-xr-attrib Attribute Extension . . . . . . . . . . 9 4.1. SDP rtcp-xr-attrib Attribute Extension .....................7
4.2. Offer/Answer Usage . . . . . . . . . . . . . . . . . . . . 9 4.2. Offer/Answer Usage .........................................7
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10 5. IANA Considerations .............................................7
5.1. New RTCP XR Block Type value . . . . . . . . . . . . . . . 10 5.1. New RTCP XR Block Type Value ...............................7
5.2. New RTCP XR SDP Parameter . . . . . . . . . . . . . . . . 10 5.2. New RTCP XR SDP Parameter ..................................7
5.3. Contact information for registrations . . . . . . . . . . 10 5.3. Contact Information for Registrations ......................7
6. Security Considerations . . . . . . . . . . . . . . . . . . . 11 6. Security Considerations .........................................8
7. Contributors . . . . . . . . . . . . . . . . . . . . . . . . . 12 7. Contributors ....................................................8
8. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 13 8. Acknowledgments .................................................8
9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 14 9. References ......................................................8
9.1. Normative References . . . . . . . . . . . . . . . . . . . 14 9.1. Normative References .......................................8
9.2. Informative References . . . . . . . . . . . . . . . . . . 14 9.2. Informative References .....................................9
Appendix A. Change Log . . . . . . . . . . . . . . . . . . . . . 15
A.1. draft-ietf-xrblock-rtcp-xr-delay-12 . . . . . . . . . . . 15
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 16
1. Introduction 1. Introduction
1.1. Packet Delay Metrics Block 1.1. Packet Delay Metrics Block
This document defines a new block type to augment those defined in This document defines a new block type to augment those defined in
[RFC3611] for use in a range of RTP applications. The new block type [RFC3611] for use in a range of RTP applications. The new block type
supports the reporting of the mean, minimum and maximum values of the supports the reporting of the mean, minimum, and maximum values of
network round-trip delay between RTP interfaces in peer RTP end the network round-trip delay between RTP interfaces in peer RTP end
systems as measured, for example, using the RTCP method described in systems as measured, for example, using the RTCP method described in
[RFC3550]. It also supports reporting of the component of the round- [RFC3550]. It also supports reporting of the component of the round-
trip delay internal to the local RTP system. trip delay internal to the local RTP system.
The network metrics belong to the class of transport metrics defined The network metrics belong to the class of transport metrics defined
in [MONARCH]. in [RFC6792].
1.2. RTCP and RTCP XR Reports 1.2. RTCP and RTCP XR Reports
The use of RTCP for reporting is defined in [RFC3550]. [RFC3611] The use of RTCP for reporting is defined in [RFC3550]. [RFC3611]
defined an extensible structure for reporting using an RTCP Extended defined an extensible structure for reporting using an RTCP Extended
Report (XR). This document defines a new Extended Report block for Report (XR). This document defines a new Extended Report block for
use with[RFC3550] and [RFC3611]. use with [RFC3550] and [RFC3611].
1.3. Performance Metrics Framework 1.3. Performance Metrics Framework
The Performance Metrics Framework [RFC6390] provides guidance on the The Performance Metrics Framework [RFC6390] provides guidance on the
definition and specification of performance metrics. The RTP definition and specification of performance metrics. The RTP
Monitoring Architectures [MONARCH] provides guideline for reporting Monitoring Architectures [RFC6792] provides guidelines for reporting
block format using RTCP XR. The Metrics Block described in this block format using RTCP XR. The metrics block described in this
document are in accordance with the guidelines in [RFC6390] and document is in accordance with the guidelines in [RFC6390] and
[MONARCH]. [RFC6792].
1.4. Applicability 1.4. Applicability
These metrics are applicable to a range of RTP applications in which These metrics are applicable to a range of RTP applications in which
this report block would be useful, such as multimedia conferencing this report block would be useful, such as multimedia conferencing
and streaming audio and video. Knowledge of the round-trip delay and and streaming audio and video. Knowledge of the round-trip delay and
delay characteristics can aid other receivers in sizing their receive delay characteristics can aid other receivers in sizing their receive
buffers and selecting a playout delay. The same information is also buffers and selecting a playout delay. The same information is also
valuable to network managers in troubleshooting network and user valuable to network managers in troubleshooting network and user
experience issues. experience issues.
skipping to change at page 5, line 8 skipping to change at page 3, line 35
2.1. Standards Language 2.1. Standards Language
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 RFC 2119 [RFC2119]. document are to be interpreted as described in RFC 2119 [RFC2119].
3. Delay Block 3. Delay Block
Metrics in this block report on packet delay in the stream arriving Metrics in this block report on packet delay in the stream arriving
at the RTP system. The measurement of these metrics are made either at the RTP system. The measurement of these metrics is made either
at the receiving end of the RTP stream or at the sending end of the at the receiving end of the RTP stream or at the sending end of the
RTP stream. Instances of this Metrics Block refer by Synchronization RTP stream. Instances of this metrics block refer by synchronization
source (SSRC) to the separate auxiliary Measurement Information block source (SSRC) to the separate auxiliary Measurement Information block
[RFC6776] which contains measurement periods (see RFC6776 section [RFC6776], which contains measurement periods (see [RFC6776], Section
4.2). This metric block relies on the measurement period in the 4.2). This metrics block relies on the measurement period in the
Measurement Information block indicating the span of the report and Measurement Information block indicating the span of the report and
SHOULD be sent in the same compound RTCP packet as the measurement SHOULD be sent in the same compound RTCP packet as the Measurement
information block. If the measurement period is not received in the Information block. If the measurement period is not received in the
same compound RTCP packet as this metric block, this metric block same compound RTCP packet as this metrics block, this metrics block
MUST be discarded. MUST be discarded.
3.1. Report Block Structure 3.1. Report Block Structure
Delay metrics block Delay metrics block
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| BT=NDEL | I | resv. | block length = 6 | | BT=16 | I | resv. | block length = 6 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| SSRC of Source | | SSRC of Source |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Mean Network Round Trip Delay | | Mean Network Round-Trip Delay |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Min Network Round Trip Delay | | Min Network Round-Trip Delay |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Max Network Round Trip Delay | | Max Network Round-Trip Delay |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| End System Delay - Seconds (bit 0-31) | | End System Delay - Seconds (bit 0-31) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| End System Delay - Fraction (bit 0-31) | | End System Delay - Fraction (bit 0-31) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 1: Report Block Structure Figure 1: Report Block Structure
3.2. Definition of Fields in Delay Metrics Report Block 3.2. Definition of Fields in Delay Metrics Report Block
Block type (BT): 8 bits Block type (BT): 8 bits
A Delay Report Block is identified by the constant NDEL. A Delay Report Block is identified by the constant 16.
[Note to RFC Editor: please replace NDEL with the IANA provided
RTCP XR block type for this block.]
Interval Metric flag (I): 2 bit Interval Metric flag (I): 2 bit
This field is used to indicate whether the Delay metrics are This field is used to indicate whether the delay metrics are
Sampled, Interval or Cumulative metrics: Sampled, Interval or Cumulative metrics:
I=10: Interval Duration - the reported value applies to the I=10: Interval Duration - the reported value applies to the
most recent measurement interval duration between successive most recent measurement interval duration between successive
metrics reports. metrics reports.
I=11: Cumulative Duration - the reported value applies to the I=11: Cumulative Duration - the reported value applies to the
accumulation period characteristic of cumulative measurements. accumulation period characteristic of cumulative measurements.
I=01: Sampled Value - the reported value is a sampled I=01: Sampled Value - the reported value is a sampled
instantaneous value. instantaneous value.
Reserved (resv): 6 bits Reserved (resv): 6 bits
These bits are reserved. They MUST be set to zero by senders and These bits are reserved. They MUST be set to zero by senders and
ignored by receivers (See RFC6709 section 4.2). ignored by receivers (see [RFC6709], Section 4.2).
block length: 16 bits block length: 16 bits
The length of this report block in 32-bit words, minus one. For The length of this report block in 32-bit words, minus one. For
the Delay block, the block length is equal to 6. the delay block, the block length is equal to 6.
SSRC of source: 32 bits SSRC of source: 32 bits
As defined in Section 4.1 of [RFC3611]. As defined in Section 4.1 of [RFC3611].
Mean Network Round Trip Delay: 32 bits Mean Network Round-Trip Delay: 32 bits
The Mean Network Round Trip Delay is the mean value of the RTP-to- The Mean Network Round-Trip Delay is the mean value of the RTP-to-
RTP interface round trip delay over the measurement period, RTP interface round-trip delay over the measurement period,
expressed in units of 1/65536 seconds. This value is typically expressed in units of 1/65536 seconds. This value is typically
determined using NTP timestamp field in the RTCP SR and LSR field determined using "the NTP timestamp field" in the RTCP sender
and DLSR field in the RTCP RR (See RFC 3550 section 6.4.1 and report (SR) and "the last SR (LSR) field","delay since last SR
figure 2). It also can be determined using NTP timestamp field in (DLSR) field" in the RTCP receiver report (RR) (see [RFC3550],
the RTCP Receiver Reference Time Report Block and LRR field and Section 6.4.1 and Figure 2). It also can be determined using "the
DLRR field in the DLRR Report Block (See RFC3611 section 4.5). NTP timestamp field" in the RTCP Receiver Reference Time Report
Block and "last RR (LRR) field", "delay since last RR (DLRR)
field" in the DLRR Report Block (see [RFC3611], Section 4.5).
If only one measurement of Round Trip Delay is available for the If only one measurement of Round-Trip Delay is available for the
timespan of the report (i.e.,the measurement period) (whether time span of the report (i.e., the measurement period) (whether
Interval or Cumulative), this single value SHOULD be reported as Interval or Cumulative), this single value SHOULD be reported as
the mean value. the mean value.
If the measurement is unavailable, the value of this field with If the measurement is unavailable, the value of this field with
all bits set to 1 MUST be reported. all bits set to 1 MUST be reported.
Min Network Round Trip Delay: 32 bits Min Network Round-Trip Delay: 32 bits
The Min Network Round Trip Delay is the minimum value of the RTP- The Min Network Round Trip Delay is the minimum value of the RTP-
to-RTP interface round trip delay over the measurement period, to-RTP interface round-trip delay over the measurement period,
expressed in units of 1/65536 seconds. This value is typically expressed in units of 1/65536 seconds. This value is typically
determined using NTP timestamp field in the RTCP SR and LSR field determined using the NTP timestamp field in the RTCP SR and LSR
and DLSR field in the RTCP RR. It also can be determined using field and DLSR field in the RTCP RR. It also can be determined
NTP timestamp field in the RTCP Receiver Reference Time Report using the NTP timestamp field in the RTCP Receiver Reference Time
Block and LRR field and DLRR field in the DLRR Report Block. Report Block and LRR field and DLRR field in the DLRR Report
Block.
If only one measurement of Round Trip Delay is available for the If only one measurement of Round Trip Delay is available for the
timespan of the report (i.e.,the measurement period) (whether time span of the report (i.e., the measurement period) (whether
Interval or Cumulative), this single value SHOULD be reported as Interval or Cumulative), this single value SHOULD be reported as
the minimum value. the minimum value.
If the measurement is unavailable, the value of this field with If the measurement is unavailable, the value of this field with
all bits set to 1 MUST be reported. all bits set to 1 MUST be reported.
Max Network Round Trip Delay: 32 bits Max Network Round-Trip Delay: 32 bits
The Max Network Round Trip Delay is the maximum value of the RTP- The Max Network Round-Trip Delay is the maximum value of the RTP-
to-RTP interface round trip delay over the measurement period, to-RTP interface round-trip delay over the measurement period,
expressed in units of 1/65536 seconds. This value is typically expressed in units of 1/65536 seconds. This value is typically
determined using NTP timestamp field in the RTCP SR and LSR field determined using the NTP timestamp field in the RTCP SR and LSR
and DLSR field in the RTCP RR. It also can be determined using field and DLSR field in the RTCP RR. It also can be determined
NTP timestamp field in the RTCP Receiver Reference Time Report using the NTP timestamp field in the RTCP Receiver Reference Time
Block and LRR field and DLRR field in the DLRR Report Block. Report Block and LRR field and DLRR field in the DLRR Report
Block.
If only one measurement of Round Trip Delay is available for the If only one measurement of Round-Trip Delay is available for the
timespan of the report (i.e.,the measurement period) (whether time span of the report (i.e.,the measurement period) (whether
Interval or Cumulative), this single value SHOULD be reported as Interval or Cumulative), this single value SHOULD be reported as
the maximum value. the maximum value.
If the measurement is unavailable, the value of this field with If the measurement is unavailable, the value of this field with
all bits set to 1 MUST be reported. all bits set to 1 MUST be reported.
End System Delay: 64 bits End System Delay: 64 bits
The End System Delay is the internal round trip delay within the The End System Delay is the internal round-trip delay within the
reporting endpoint, calculated using the nominal value of the reporting endpoint, calculated using the nominal value of the
jitter buffer delay plus the accumulation/encoding and decoding/ jitter buffer delay plus the accumulation/encoding and decoding/
playout delay associated with the codec being used. The value of playout delay associated with the codec being used. The value of
this field is represented using a 64-bit NTP-format timestamp as this field is represented using a 64-bit NTP-format timestamp as
defined in [RFC5905], which is 64-bit unsigned fixed-point number defined in [RFC5905], which is a 64-bit unsigned fixed-point
with the integer part in the first 32 bits and the fractional part number with the integer part in the first 32 bits and the
in the last 32 bits. fractional part in the last 32 bits.
If the measurement is unavailable, the value of this field with If the measurement is unavailable, the value of this field with
all bits set to 1 MUST be reported. all bits set to 1 MUST be reported.
4. SDP Signaling 4. SDP Signaling
[RFC3611] defines the use of SDP (Session Description Protocol) [RFC3611] defines the use of SDP (Session Description Protocol)
[RFC4566] for signaling the use of XR blocks. XR blocks MAY be used [RFC4566] for signaling the use of XR blocks. XR blocks MAY be used
without prior signaling. without prior signaling.
skipping to change at page 9, line 23 skipping to change at page 7, line 17
This section augments the SDP [RFC4566] attribute "rtcp-xr" defined This section augments the SDP [RFC4566] attribute "rtcp-xr" defined
in [RFC3611] by providing an additional value of "xr-format" to in [RFC3611] by providing an additional value of "xr-format" to
signal the use of the report block defined in this document. signal the use of the report block defined in this document.
xr-format =/ xr-delay-block xr-format =/ xr-delay-block
xr-delay-block ="delay" xr-delay-block ="delay"
4.2. Offer/Answer Usage 4.2. Offer/Answer Usage
When SDP is used in offer-answer context, the SDP Offer/Answer usage When SDP is used in offer/answer context, the SDP Offer/Answer usage
defined in [RFC3611] applies. defined in [RFC3611] applies.
5. IANA Considerations 5. IANA Considerations
New block types for RTCP XR are subject to IANA registration. For New block types for RTCP XR are subject to IANA registration. For
general guidelines on IANA considerations for RTCP XR, refer to general guidelines on IANA considerations for RTCP XR, refer to
[RFC3611]. [RFC3611].
5.1. New RTCP XR Block Type value 5.1. New RTCP XR Block Type Value
This document assigns the block type value NDEL in the IANA "RTCP XR
Block Type Registry" to the "Delay Metrics Block".
[Note to RFC Editor: please replace NDEL with the IANA provided RTCP This document assigns the block type value 16 in the IANA "RTP
XR block type for this block.] Control Protocol Extended Reports (RTCP XR) Block Type Registry" to
the "Delay Metrics Block".
5.2. New RTCP XR SDP Parameter 5.2. New RTCP XR SDP Parameter
This document also registers a new parameter "delay" in the "RTCP XR This document also registers a new parameter "delay" in the "RTP
SDP Parameters Registry". Control Protocol Extended Reports (RTCP XR) Session Description
Protocol (SDP) Parameters" registry.
5.3. Contact information for registrations 5.3. Contact Information for Registrations
The contact information for the registrations is: The contact information for the registrations is:
Qin Wu (sunseawq@huawei.com) Qin Wu (sunseawq@huawei.com)
Huawei
101 Software Avenue, Yuhua District 101 Software Avenue, Yuhua District
Nanjing, Jiangsu 210012 Nanjing, Jiangsu 210012
China China
6. Security Considerations 6. Security Considerations
It is believed that this proposed RTCP XR report block introduces no It is believed that this proposed RTCP XR report block introduces no
new security considerations beyond those described in [RFC3611]. new security considerations beyond those described in [RFC3611].
This block does not provide per-packet statistics, so the risk to This block does not provide per-packet statistics, so the risk to
confidentiality documented in Section 7, paragraph 3 of [RFC3611] confidentiality documented in Section 7, paragraph 3, of [RFC3611]
does not apply. does not apply.
7. Contributors 7. Contributors
Geoff Hunt wrote the initial version of this document. Geoff Hunt wrote the initial version of this document.
8. Acknowledgments 8. Acknowledgments
The authors gratefully acknowledge the comments and contributions The authors gratefully acknowledge the comments and contributions
made by Bruce Adams, Philip Arden, Amit Arora, Bob Biskner, Kevin made by Bruce Adams, Philip Arden, Amit Arora, Bob Biskner, Kevin
Connor, Claus Dahm, Randy Ethier, Roni Even, Jim Frauenthal, Albert Connor, Claus Dahm, Randy Ethier, Roni Even, Jim Frauenthal, Albert
Higashi, Tom Hock, Shane Holthaus, Paul Jones, Rajesh Kumar, Keith Higashi, Tom Hock, Shane Holthaus, Paul Jones, Rajesh Kumar, Keith
Lantz, Mohamed Mostafa, Amy Pendleton, Colin Perkins, Mike Ramalho, Lantz, Mohamed Mostafa, Amy Pendleton, Colin Perkins, Mike Ramalho,
Ravi Raviraj, Albrecht Schwarz, Tom Taylor, and Hideaki Yamada,Jing Ravi Raviraj, Albrecht Schwarz, Tom Taylor, and Hideaki Yamada, Jing
Zhao,Kevin Gross, Colin Perkins, Charles Eckel, Glen Zorn,Shida Zhao, Kevin Gross, Colin Perkins, Charles Eckel, Glen Zorn, Shida
Schubert,Barry Leiba,Sean Turner,Robert Sparks,Benoit Claise,Stephen Schubert, Barry Leiba, Sean Turner, Robert Sparks, Benoit Claise, and
Farrell. Stephen Farrell.
9. References 9. References
9.1. Normative References 9.1. 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", March 1997. Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC3550] Schulzrinne, H., "RTP: A Transport Protocol for Real-Time [RFC3550] Schulzrinne, H., Casner, S., Frederick, R., and V.
Applications", RFC 3550, July 2003. Jacobson, "RTP: A Transport Protocol for Real-Time
Applications", STD 64, RFC 3550, July 2003.
[RFC3611] Friedman, T., Caceres, R., and A. Clark, "RTP Control [RFC3611] Friedman, T., Caceres, R., and A. Clark, "RTP Control
Protocol Extended Reports (RTCP XR)", November 2003. Protocol Extended Reports (RTCP XR)", RFC 3611,
November 2003.
[RFC4566] Handley, M., Jacobson, V., and C. Perkins, "SDP: Session [RFC4566] Handley, M., Jacobson, V., and C. Perkins, "SDP: Session
Description Protocol", July 2006. Description Protocol", RFC 4566, July 2006.
[RFC5905] Mills, D., Martin, J., Burbank, J., and W. Kasch, "Network [RFC5905] Mills, D., Martin, J., Burbank, J., and W. Kasch, "Network
Time Protocol Version 4: Protocol and Algorithms Time Protocol Version 4: Protocol and Algorithms
Specification", RFC 5905, June 2010. Specification", RFC 5905, June 2010.
[RFC6709] Carpenter, B., Aboba, B., and S. Cheshire, "Design [RFC6709] Carpenter, B., Aboba, B., and S. Cheshire, "Design
Considerations for Protocol Extensions", RFC 6709, Considerations for Protocol Extensions", RFC 6709,
September 2012. September 2012.
9.2. Informative References 9.2. Informative References
[MONARCH] Hunt, G., "Monitoring Architectures for RTP", [RFC6390] Clark, A. and B. Claise, "Guidelines for Considering New
ID draft-ietf-avtcore-monarch-22, September 2012. Performance Metric Development", BCP 170, RFC 6390,
October 2011.
[RFC6390] Clark, A. and B. Claise, "Framework for Performance Metric
Development", RFC 6390, October 2011.
[RFC6776] Hunt, G., "Measurement Identity and information Reporting
using SDES item and XR Block", RFC 6776, October 2012.
Appendix A. Change Log
Note to the RFC-Editor: please remove this section prior to
publication as an RFC.
A.1. draft-ietf-xrblock-rtcp-xr-delay-12
The following are the major changes to previous version : [RFC6776] Clark, A. and Q. Wu, "Measurement Identity and Information
Reporting Using a Source Description (SDES) Item and an
RTCP Extended Report (XR) Block", RFC 6776, October 2012.
o Remove SHOULD from reserved field and add reference to RFC6709. [RFC6792] Wu, Q., Hunt, G., and P. Arden, "Guidelines for Use of the
RTP Monitoring Framework", RFC 6792, November 2012.
Authors' Addresses Authors' Addresses
Alan Clark Alan Clark
Telchemy Incorporated Telchemy Incorporated
2905 Premiere Parkway, Suite 280 2905 Premiere Parkway, Suite 280
Duluth, GA 30097 Duluth, GA 30097
USA USA
Email: alan.d.clark@telchemy.com EMail: alan.d.clark@telchemy.com
Kevin Gross Kevin Gross
AVA Networks AVA Networks
Email: kevin.gross@avanw.com EMail: kevin.gross@avanw.com
Qin Wu Qin Wu
Huawei Huawei
101 Software Avenue, Yuhua District 101 Software Avenue, Yuhua District
Nanjing, Jiangsu 210012 Nanjing, Jiangsu 210012
China China
Email: sunseawq@huawei.com EMail: sunseawq@huawei.com
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