Audio/Video Transport Working Group A. Clark
Internet-Draft Telchemy
Intended status: Standards Track S. Zhang
Expires: October 17, 2013 J. Zhao
STTRI
Q. Wu, Ed.
Huawei
April 15, 2013
RTP Control Protocol (RTCP) Extended Report (XR) Block for Burst/Gap
Loss metric Reporting
draft-ietf-xrblock-rtcp-xr-burst-gap-loss-12.txt
Abstract
This document defines an RTP Control Protocol (RTCP) Extended Report
(XR) Block that allows the reporting of Burst and Gap Loss metrics
for use in a range of RTP applications.
Status of this Memo
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provisions of BCP 78 and BCP 79.
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This Internet-Draft will expire on October 17, 2013.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Burst and Gap Loss Report Block . . . . . . . . . . . . . 3
1.2. RTCP and RTCP XR Reports . . . . . . . . . . . . . . . . . 3
1.3. Performance Metrics Framework . . . . . . . . . . . . . . 3
1.4. Applicability . . . . . . . . . . . . . . . . . . . . . . 4
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.1. Standards Language . . . . . . . . . . . . . . . . . . . . 5
3. Burst/Gap Loss Block . . . . . . . . . . . . . . . . . . . . . 6
3.1. Report Block Structure . . . . . . . . . . . . . . . . . . 6
3.2. Definition of Fields in Burst/Gap Loss Report Block . . . 6
3.3. Derived metrics based on reported metrics . . . . . . . . 9
4. Considerations for Voice-over-IP applications . . . . . . . . 11
5. SDP Signaling . . . . . . . . . . . . . . . . . . . . . . . . 12
5.1. SDP rtcp-xr-attrib Attribute Extension . . . . . . . . . . 12
5.2. Offer/Answer Usage . . . . . . . . . . . . . . . . . . . . 12
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13
6.1. New RTCP XR Block Type value . . . . . . . . . . . . . . . 13
6.2. New RTCP XR SDP Parameter . . . . . . . . . . . . . . . . 13
6.3. Contact information for registrations . . . . . . . . . . 13
7. Security Considerations . . . . . . . . . . . . . . . . . . . 14
8. Contributors . . . . . . . . . . . . . . . . . . . . . . . . . 15
9. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 16
10. References . . . . . . . . . . . . . . . . . . . . . . . . . . 17
10.1. Normative References . . . . . . . . . . . . . . . . . . . 17
10.2. Informative References . . . . . . . . . . . . . . . . . . 17
Appendix A. Metrics represented using RFC6390 Template . . . . . 18
Appendix B. Change Log . . . . . . . . . . . . . . . . . . . . . 23
B.1. draft-ietf-xrblock-rtcp-xr-burst-gap-loss-11 . . . . . . . 23
B.2. draft-ietf-xrblock-rtcp-xr-burst-gap-loss-10 . . . . . . . 23
B.3. draft-ietf-xrblock-rtcp-xr-burst-gap-loss-09 . . . . . . . 23
B.4. draft-ietf-xrblock-rtcp-xr-burst-gap-loss-08 . . . . . . . 23
B.5. draft-ietf-xrblock-rtcp-xr-burst-gap-loss-07 . . . . . . . 23
B.6. draft-ietf-xrblock-rtcp-xr-burst-gap-loss-06 . . . . . . . 23
B.7. draft-ietf-xrblock-rtcp-xr-burst-gap-loss-04 . . . . . . . 24
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 25
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1. Introduction
1.1. Burst and Gap Loss Report Block
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
supports the reporting of the proportion of packets lost by the
network. The losses during loss bursts are reported, together with
the number of bursts and additional data allowing the calculation of
statistical parameters (mean and variance) of the distribution of
burst lengths. Some uses of these metrics depend on the availability
of the metric "cumulative number of packets lost" from RTCP
[RFC3550].
This block provides information on transient IP problems. Burst/Gap
metrics are typically used in Cumulative reports, however they also
may be used in Interval reports. The burstiness of packet loss
affects user experience, may influence any sender strategies to
mitigate the problem, and may also have diagnostic value.
The metric belongs to the class of transport-related end system
metrics defined in [RFC6792].
The definitions of Burst, Gap, Loss and Discard are consistent with
definitions in [RFC3611]. To accommodate the range of jitter buffer
algorithms and packet discard logic that may be used by implementors,
the method used to distinguish between bursts and gaps may be an
equivalent method to that defined in [RFC3611]. The method used
should produce the same result as that defined in [RFC3611] for
conditions of burst packet loss, but may produce different results
for conditions of time varying jitter.
1.2. RTCP and RTCP XR Reports
The use of RTCP for reporting is defined in [RFC3550]. [RFC3611]
defined an extensible structure for reporting using an RTCP Extended
Report (XR). This document defines a new Extended Report block for
use with [RFC3550] and [RFC3611].
1.3. Performance Metrics Framework
The Performance Metrics Framework [RFC6390] provides guidance on the
definition and specification of performance metrics. The RTP
Monitoring Architectures [RFC6792] provides guideline for reporting
block format using RTCP XR. The Metrics Block described in this
document are in accordance with the guidelines in [RFC6390] and
[RFC6792].
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1.4. Applicability
These metrics are applicable to a range of RTP applications which
contain jitter buffers and don't use stream repair means, e.g.,
Forward Error Correction (FEC) [RFC5109] and/or retransmission
[RFC4588].
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2. Terminology
2.1. Standards Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119].
In addition, the following terms are defined:
Received, Lost and Discarded
A packet shall be regarded as lost if it fails to arrive within an
implementation-specific time window. A packet that arrives within
this time window but is too early or late to be played out or
thrown away before playout due to packet duplication or redundancy
shall be regarded as discarded. A packet shall be classified as
one of received (or OK), discarded or lost. The metric
"cumulative number of packets lost" defined in [RFC3550] reports a
count of packets lost from the media stream (single SSRC within
single RTP session). Similarly the metric "number of packets
discarded" defined in [DISCARD] reports a count of packets
discarded from the media stream (single SSRC within single RTP
session) arriving at the receiver. Another metric defined in
[RFC5725] is available to report on packets which are not
recovered by any repair techniques which may be in use.
Bursts and Gaps
The terms Burst and Gap are used in a manner consistent with that
of RTCP XR [RFC3611]. RTCP XR views a RTP stream as being divided
into bursts, which are periods during which the loss rate is high
enough to cause noticeable quality degradation (generally over 5
percent loss rate), and gaps, which are periods during which lost
packets are infrequent and hence quality is generally acceptable.
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3. Burst/Gap Loss Block
Metrics in this block report on Burst/Gap Loss in the stream arriving
at the RTP system. The measurement of these metrics are made at the
receiving end of the RTP stream. Instances of this Metrics Block
refer by Synchronization source (SSRC) to the separate auxiliary
Measurement Information block [RFC6776] which describes measurement
periods in use(see RFC6776 section 4.2).
This Metrics Block relies on the measurement period in the
Measurement Information block indicating the span of the report.
Senders MUST send this block in the same compound RTCP packet as the
measurement information block. Receivers MUST verify that the
measurement period is received in the same compound RTCP packet as
this Metrics Block. If not, this Metrics Block MUST be discarded.
3.1. Report Block Structure
Burst/Gap Loss metrics block
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| BT=NBGL | I |C| resv. | block length = 5 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| SSRC of Source |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Threshold | Sum of Burst Durations (ms) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Packets Lost in Bursts | Total... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ...Packets expected in bursts | Number of bursts | Sum of|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ...Squares of Burst Durations (ms-squared) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 1: Report Block Structure
3.2. Definition of Fields in Burst/Gap Loss Report Block
Block type (BT): 8 bits
A Burst/Gap Loss Report Block is identified by the constant NBGL.
[Note to RFC Editor: please replace NBGL with the IANA provided
RTCP XR block type for this block.]
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Interval Metric flag (I): 2 bits
This field is used to indicate whether the Burst/Gap Loss metrics
are Sampled, Interval or Cumulative metrics:
I=10: Interval Duration - the reported value applies to the
most recent measurement interval duration between successive
metrics reports.
I=11: Cumulative Duration - the reported value applies to the
accumulation period characteristic of cumulative measurements.
I=01: Sampled Value - the reported value is a sampled
instantaneous value.
In this document, Burst/Gap Loss Metrics can only be measured over
definite intervals, and cannot be sampled. Also, the value I=00
is reserved for future use. Senders MUST NOT use the values I=00
or I=01. If a block is received with I=00 or I=01, the receiver
MUST discard the block.
Loss and Discard Combination flag (C): 1 bit
The 'C' flag is used to indicate whether the loss/discard report
is combined with the burst gap loss report in the same compound
RTCP packet. The value is set to '1' if the loss/discard report
and the burst gap loss report are combined. Otherwise, the value
is set to '0'. If the 'C' flag is set to 1 but the burst gap
discard was not sent, the receiver MUST discard the burst gap
loss.
Reserved (resv): 5 bits
These bits are reserved. They MUST be set to zero by senders and
ignored by receivers (See RFC6709 section 4.2).
block length: 16 bits
The length of this report block in 32-bit words, minus one. For
the Burst/Gap Loss block, the block length is equal to 5. The
block MUST be discarded if the block length is set to a different
value.
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SSRC of source: 32 bits
As defined in Section 4.1 of [RFC3611].
Threshold: 8 bits
The Threshold is equivalent to Gmin in [RFC3611], i.e. the number
of successive packets that must be received prior to and following
a lost packet in order for this lost packet to be regarded as part
of a gap. Note that the threshold is calculated in accordance
with Gmin Calculation defined in section 4.7.2 of RFC3611.
Sum of Burst Durations (ms): 24 bits
The total duration of bursts of lost packets in the period of the
report (Interval or Cumulative).
The measured value is unsigned value. If the measured value
exceeds 0xFFFFFD, the value 0xFFFFFE MUST be reported to indicate
an over-range measurement. If the measurement is unavailable, the
value 0xFFFFFF MUST be reported.
Packets lost in bursts: 24 bits
The total number of packets lost during loss bursts.
The measured value is unsigned value. If the measured value
exceeds 0xFFFFFD, the value 0xFFFFFE MUST be reported to indicate
an over-range measurement. If the measurement is unavailable, the
value 0xFFFFFF MUST be reported.
Total packets expected in bursts: 24 bits
The total number of packets expected during loss bursts (that is,
the sum of received packets and lost packets).
The measured value is unsigned value. If the measured value
exceeds 0xFFFFFD, the value 0xFFFFFE MUST be reported to indicate
an over-range measurement. If the measurement is unavailable, the
value 0xFFFFFF MUST be reported.
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Number of bursts: 16 bits
The number of bursts in the period of the report (Interval or
Cumulative).
The measured value is unsigned value. If the measured value
exceeds 0xFFFD, the value 0xFFFE MUST be reported to indicate an
over-range measurement. If the measurement is unavailable, the
value 0xFFFF MUST be reported.
Sum of Squares of Burst Durations (ms-squared): 36 bits
The sum of the squares of burst durations (where individual burst
durations are expressed in ms) over in the period of the report
(Interval or Cumulative). The units for this quantity are
milliseconds-squared.
The measured value is unsigned value. If the measured value
exceeds 0xFFFFFFFFD, the value 0xFFFFFFFFE MUST be reported to
indicate an over-range measurement. If the measurement is
unavailable, the value 0xFFFFFFFFF MUST be reported.
3.3. Derived metrics based on reported metrics
The metrics described here are intended to be used as described in
this section, in conjunction with information from the Measurement
Information block [RFC6776] and also with the metric "cumulative
number of packets lost" provided in standard RTCP [RFC3550].
These metrics provide information relevant to statistical parameters,
including:
o The fraction of packets lost during bursts (i.e., Burst Loss Rate
in [SUMSTAT]), which can be calculated using the metric " Packets
Loss in Bursts " and the metric " Total Packets expected in Bursts
" provided in the Burst/Gap Loss metrics block.
o The fraction of packets lost during gaps (i.e., Gap Loss Rate in
[SUMSTAT]), which can be calculated using the metric " Packets
Loss in Bursts " and the metric " Total Packets expected in Bursts
" provided in the Burst/Gap Loss metrics block.
o burst duration mean [SUMSTAT], which can be calculated using the
metric " Packets Loss in Bursts " and the metric " Total Packets
expected in Bursts " provided in the Burst/Gap Loss metrics block.
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o burst duration variance [SUMSTAT], which can be calculated using
the metric " Packets Loss in Bursts " and the metric " Total
Packets expected in Bursts " provided in the Burst/Gap Loss
metrics block.
The details on calculation these parameters in the metrics are
described in [SUMSTAT].
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4. Considerations for Voice-over-IP applications
This Metrics Block is applicable to a broad range of RTP
applications. Where the metric is used with a Voice-overIP (VoIP)
application and the stream repair means is not available, the
following considerations apply.
RTCP XR views a call as being divided into bursts, which are periods
during which the loss rate is high enough to cause noticeable call
quality degradation (generally over 5 percent loss rate), and gaps,
which are periods during which lost packets are infrequent and hence
call quality is generally acceptable.
If Voice Activity Detection is used, the Burst and Gap Duration shall
be determined as if silence packets had been sent, i.e. a period of
silence in excess of Gmin packets will terminate a burst condition.
The recommended value for the threshold Gmin in [RFC3611] results in
a Burst being a period of time during which the call quality is
degraded to a similar extent to a typical Pulse-Code Modulation(PCM)
Severely Errored Second.
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5. SDP Signaling
[RFC3611] defines the use of SDP (Session Description Protocol)
[RFC4566] for signaling the use of XR blocks. XR blocks MAY be used
without prior signaling.
5.1. SDP rtcp-xr-attrib Attribute Extension
This section augments the SDP [RFC4566] attribute "rtcp-xr" defined
in [RFC3611] by providing an additional value of "xr-format" to
signal the use of the report block defined in this document.
xr-format =/ xr-bgl-block
xr-bgl-block = "burst-gap-loss"
5.2. Offer/Answer Usage
When SDP is used in offer-answer context, the SDP Offer/Answer usage
defined in [RFC3611] for unilateral "rtcp-xr" attribute parameters
applies. For detailed usage in Offer/Answer for unilateral
parameter, refer to section 5.2 of [RFC3611].
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6. IANA Considerations
New block types for RTCP XR are subject to IANA registration. For
general guidelines on IANA considerations for RTCP XR, refer to
[RFC3611].
6.1. New RTCP XR Block Type value
This document assigns the block type value NBGL in the IANA " RTP
Control Protocol Extended Reports (RTCP XR) Block Type Registry " to
the "Burst/Gap Loss Metrics Block".
[Note to RFC Editor: please replace NBGL with the IANA provided RTCP
XR block type for this block.]
6.2. New RTCP XR SDP Parameter
This document also registers a new parameter "burst-gap-loss" in the
" RTP Control Protocol Extended Reports (RTCP XR) Session Description
Protocol (SDP) Parameters Registry".
6.3. Contact information for registrations
The contact information for the registrations is:
Qin Wu (sunseawq@huawei.com)
101 Software Avenue, Yuhua District
Nanjing, Jiangsu 210012
China
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7. Security Considerations
This block does not provide per-packet statistics, so the risk to
confidentiality documented in Section 7, paragraph 3 of [RFC3611]
does not apply. However the gaps indicated within this block could
be used to detect the timing of other events on the path between the
sender and receiver. For example, a competing multimedia stream
might cause a loss burst for the duration of the stream, allowing the
receiver of this block to know when the competing stream was active.
This risk is not a significant threat since the only information
leaked is the timing of the loss, not the cause. Besides this, it is
believed that this proposed RTCP XR report block introduces no other
new security considerations beyond those described in [RFC3611].
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8. Contributors
Geoff Hunt wrote the initial draft of this document.
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9. Acknowledgments
The authors gratefully acknowledge reviews and feedback provided by
Bruce Adams, Philip Arden, Amit Arora, Bob Biskner, Kevin Connor,
Claus Dahm, Randy Ethier, Roni Even, Jim Frauenthal, Albert Higashi,
Tom Hock, Shane Holthaus, Paul Jones, Rajesh Kumar, Keith Lantz,
Mohamed Mostafa, Amy Pendleton, Colin Perkins, Mike Ramalho, Ravi
Raviraj, Albrecht Schwarz, Tom Taylor, Hideaki Yamada, Adam Roach,
Dan Romascanu,Chris Lonvick, Alfred C.,Morton Jr., Pete Resnick, Ted
Lemon, Stephen Farrell, Richard Barnes, Benoit Claise.
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10. References
10.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", March 1997.
[RFC3550] Schulzrinne, H., "RTP: A Transport Protocol for Real-Time
Applications", RFC 3550, July 2003.
[RFC3611] Friedman, T., Caceres, R., and A. Clark, "RTP Control
Protocol Extended Reports (RTCP XR)", November 2003.
[RFC4566] Handley, M., Jacobson, V., and C. Perkins, "SDP: Session
Description Protocol", July 2006.
[RFC5725] Begen, A., Hsu, D., and M. Lague, "Post-Repair Loss RLE
Report Block Type for RTP Control Protocol (RTCP) Extended
Reports (XRs)", RFC 5725, February 2020.
10.2. Informative References
[DISCARD] Wu, Q., "RTCP XR Report Block for Discard metric
Reporting", ID draft-ietf-xrblock-rtcp-xr-discard-11,
December 2012.
[RFC4588] Rey, J., Leon, D., , A., Varsa, V., and R. Hakenberg, "RTP
Retransmission Payload Format", RFC 4588, July 2006.
[RFC5109] Li, A., "RTP Payload Format for Generic Forward Error
Correction", RFC 5109, December 2007.
[RFC6390] Clark, A. and B. Claise, "Framework for Performance Metric
Development", RFC 6390, July 2011.
[RFC6709] Carpenter, B., Aboba, B., and S. Cheshire, "Design
Considerations for Protocol Extensions", RFC 6709,
September 2012.
[RFC6776] Wu, Q., "Measurement Identity and information Reporting
using SDES item and XR Block", RFC 6776, October 2012.
[RFC6792] Hunt, G., "Monitoring Architectures for RTP", RFC 6792,
November 2012.
[SUMSTAT] Zorn, G., "RTCP XR for Summary Statistics Metrics
Reporting", ID draft-ietf-xrblock-rtcp-xr-summary-stat-11,
March 2013.
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Appendix A. Metrics represented using RFC6390 Template
RFC EDITOR NOTE: please change XXXX in [RFCXXXX] by the new RFC
number, when assigned.
a. Threshold Metric
* Metric Name: Threshold in RTP
* Metric Description: The Threshold is equivalent to Gmin in
[RFC3611], i.e. the number of successive RTP packets that must
be received prior to and following a lost RTP packet in order
for this lost RTP packet to be regarded as part of a gap.
* Method of Measurement or Calculation: See section 3.2,
Threshold definition [RFCXXXX].
* Units of Measurement: See section 3.2, Threshold definition
[RFCXXXX].
* Measurement Point(s) with Potential Measurement Domain: See
section 3, 1st paragraph [RFCXXXX].
* Measurement Timing: See section 3, 2nd paragraph [RFCXXXX] for
measurement timing and section 3.2 [RFCXXXX] for Interval
Metric flag.
* Use and applications: See section 1.4 [RFCXXXX].
* Reporting model: See RFC3611.
b. Sum of Burst Durations Metric
* Metric Name: Sum of Burst Durations in RTP
* Metric Description: The total duration of bursts of lost RTP
packets in the period of the report.
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* Method of Measurement or Calculation: See section 3.2, Sum of
Burst Durations definition [RFCXXXX].
* Units of Measurement: See section 3.2, Sum of Burst Durations
definition [RFCXXXX].
* Measurement Point(s) with Potential Measurement Domain: See
section 3, 1st paragraph [RFCXXXX].
* Measurement Timing: See section 3, 2nd paragraph [RFCXXXX] for
measurement timing and section 3.2 [RFCXXXX] for Interval
Metric flag.
* Use and applications: See section 1.4 [RFCXXXX].
* Reporting model: See RFC3611.
c. Packets lost in bursts Metric
* Metric Name: RTP Packets lost in bursts
* Metric Description: The total number of RTP packets lost
during loss bursts.
* Method of Measurement or Calculation: See section 3.2, Packets
lost in bursts definition [RFCXXXX].
* Units of Measurement: See section 3.2, Packets lost in bursts
definition [RFCXXXX].
* Measurement Point(s) with Potential Measurement Domain: See
section 3, 1st paragraph [RFCXXXX].
* Measurement Timing: See section 3, 2nd paragraph [RFCXXXX] for
measurement timing and section 3.2 [RFCXXXX] for Interval
Metric flag.
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* Use and applications: See section 1.4 [RFCXXXX].
* Reporting model: See RFC3611.
d. Total packets expected in bursts Metric
* Metric Name: Total RTP packets expected in bursts
* Metric Description: The total number of RTP packets expected
during loss bursts (that is, the sum of received RTP packets
and lost RTP packets).
* Method of Measurement or Calculation: See section 3.2, Total
packets expected in bursts definition [RFCXXXX].
* Units of Measurement: See section 3.2, Total packets expected
in bursts definition [RFCXXXX].
* Measurement Point(s) with Potential Measurement Domain: See
section 3, 1st paragraph [RFCXXXX].
* Measurement Timing: See section 3, 2nd paragraph [RFCXXXX] for
measurement timing and section 3.2 [RFCXXXX] for Interval
Metric flag.
* Use and applications: See section 1.4 [RFCXXXX].
* Reporting model: See RFC3611.
e. Number of bursts Metric
* Metric Name: Number of bursts in RTP
* Metric Description: The total duration of bursts of lost RTP
packets in the period of the report.
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* Method of Measurement or Calculation: See section 3.2, Number
of bursts definition [RFCXXXX].
* Units of Measurement: See section 3.2, Number of bursts
definition [RFCXXXX].
* Measurement Point(s) with Potential Measurement Domain: See
section 3, 1st paragraph [RFCXXXX].
* Measurement Timing: See section 3, 2nd paragraph [RFCXXXX] for
measurement timing and section 3.2 [RFCXXXX] for Interval
Metric flag.
* Use and applications: See section 1.4 [RFCXXXX].
* Reporting model: See RFC3611.
f. Sum of Squares of Burst Durations Metric
* Metric Name: Sum of Squares of Burst Durations in RTP
* Metric Description: The sum of the squares of burst durations
(where individual burst durations are expressed in ms) over in
the period of the report.
* Method of Measurement or Calculation: See section 3.2, Sum of
Squares of Burst Durations definition [RFCXXXX].
* Units of Measurement: See section 3.2, Sum of Squares of Burst
Durations definition [RFCXXXX].
* Measurement Point(s) with Potential Measurement Domain: See
section 3, 1st paragraph [RFCXXXX].
* Measurement Timing: See section 3, 2nd paragraph [RFCXXXX] for
measurement timing and section 3.2 [RFCXXXX] for Interval
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Metric flag.
* Use and applications: See section 1.4 [RFCXXXX].
* Reporting model: See RFC3611.
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Appendix B. Change Log
Note to the RFC-Editor: please remove this section prior to
publication as an RFC.
B.1. draft-ietf-xrblock-rtcp-xr-burst-gap-loss-11
The following are the major changes compared to previous version:
o Incorporated Ted's proposed change during IESG review.
B.2. draft-ietf-xrblock-rtcp-xr-burst-gap-loss-10
The following are the major changes compared to previous version:
o IESG Review comments are addressed in this version.
B.3. draft-ietf-xrblock-rtcp-xr-burst-gap-loss-09
The following are the major changes compared to previous version:
o IETF LC comments are addressed together with AD's comment on
Normative language in this version.
B.4. draft-ietf-xrblock-rtcp-xr-burst-gap-loss-08
The following are the major changes compared to previous version:
o Move RFC6709 as one informative reference.
B.5. draft-ietf-xrblock-rtcp-xr-burst-gap-loss-07
The following are the major changes compared to previous version:
o Editorial changes based on comments in the WGLC.
B.6. draft-ietf-xrblock-rtcp-xr-burst-gap-loss-06
The following are the major changes compared to previous version:
o SDP update based on SDP Directorate Review.
o Add some texts to get consistent with RFC6798 and Delay draft.
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B.7. draft-ietf-xrblock-rtcp-xr-burst-gap-loss-04
The following are the major changes compared to previous version:
o Outdated reference update.
o Editorial changes based on comments that applied to PDV and Delay
drafts.
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Authors' Addresses
Alan Clark
Telchemy Incorporated
2905 Premiere Parkway, Suite 280
Duluth, GA 30097
USA
Email: alan.d.clark@telchemy.com
Sunshine Zhang
Shanghai Research Institute of China Telecom Corporation Limited
No.1835,South Pudong Road
Shanghai 200122
China
Email: zhangyx@sttri.com.cn
Jing Zhao
Shanghai Research Institute of China Telecom Corporation Limited
No.1835,South Pudong Road
Shanghai 200122
China
Email: zhaojing@sttri.com.cn
Qin Wu (editor)
Huawei
101 Software Avenue, Yuhua District
Nanjing, Jiangsu 210012
China
Email: sunseawq@huawei.com
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