Audio/Video Transport Working GroupInternet Engineering Task Force (IETF) A. ClarkInternet-DraftRequest for Comments: 7003 TelchemyIntended status:Category: Standards Track R. HuangExpires: October 28, 2013ISSN: 2070-1721 Q. Wu, Ed. HuaweiApril 26,August 2013 RTP ControlProtocol(RTCP)Protocol (RTCP) Extended Report (XR) Block for Burst/Gap DiscardmetricMetric Reportingdraft-ietf-xrblock-rtcp-xr-burst-gap-discard-14.txtAbstract This document defines an RTP ControlProtocol(RTCP)Protocol (RTCP) Extended Report (XR)Blockblock that allows the reporting ofBurstburst andGap Discardgap discard metrics for use in a range of RTP applications. Status ofthisThis Memo ThisInternet-Draftissubmitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documentsan Internet Standards Track document. This document is a product of the Internet Engineering Task Force (IETF).Note that other groups may also distribute working documents as Internet-Drafts. The listIt represents the consensus ofcurrent Internet- Drafts is at http://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents validthe IETF community. It has received public review and has been approved fora maximumpublication by the Internet Engineering Steering Group (IESG). Further information on Internet Standards is available in Section 2 of RFC 5741. Information about the current status ofsix monthsthis document, any errata, and how to provide feedback on it may beupdated, replaced, or obsoleted by other documentsobtained atany time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." This Internet-Draft will expire on October 28, 2013.http://www.rfc-editor.org/info/rfc7003. Copyright Notice Copyright (c) 2013 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Introduction. . . . . . . . . . . . . . . . . . . . . . . . . 3....................................................2 1.1.Burst and GapBurst/Gap DiscardReportMetrics Block. . . . . . . . . . . . 3............................2 1.2. RTCP and RTCPXRExtended Reports. . . . . . . . . . . . . . . . . 3.............................3 1.3. Performance Metrics Framework. . . . . . . . . . . . . . 3..............................3 1.4. Applicability. . . . . . . . . . . . . . . . . . . . . . 4..............................................3 2. Terminology. . . . . . . . . . . . . . . . . . . . . . . . . 5 2.1. Standards Language . . . . . . . . . . . . . . . . . . . . 5.....................................................3 3. Burst/Gap Discard Metrics Block. . . . . . . . . . . . . . . . . . . 6.................................4 3.1. Report Block Structure. . . . . . . . . . . . . . . . . . 6.....................................5 3.2. Definition of Fields in Burst/Gap DiscardReportMetrics Block. . 6....5 3.3. Derivedmetrics basedMetrics Based onreported metrics . . . . . . . . 8Reported Metrics ..................7 4. Considerations for Voice-over-IPapplications . . . . . . . . 10Applications ...................7 5. SDP Signaling. . . . . . . . . . . . . . . . . . . . . . . . 11...................................................8 5.1. SDPrtcp-xr-attribrtcp-xr Attribute Extension. . . . . . . . . . 11............................8 5.2. Offer/Answer Usage. . . . . . . . . . . . . . . . . . . . 11.........................................8 6. IANA Considerations. . . . . . . . . . . . . . . . . . . . . 12.............................................8 6.1. New RTCP XR Block Typevalue . . . . . . . . . . . . . . . 12Value ...............................8 6.2. New RTCP XR SDP Parameter. . . . . . . . . . . . . . . . 12..................................9 6.3. ContactinformationInformation forregistrations . . . . . . . . . . 12Registrations ......................9 7. Security Considerations. . . . . . . . . . . . . . . . . . . 13.........................................9 8. Contributors. . . . . . . . . . . . . . . . . . . . . . . . . 14....................................................9 9. Acknowledgments. . . . . . . . . . . . . . . . . . . . . . . 15.................................................9 10. References. . . . . . . . . . . . . . . . . . . . . . . . . . 16....................................................10 10.1. Normative References. . . . . . . . . . . . . . . . . . . 16.....................................10 10.2. Informative References. . . . . . . . . . . . . . . . . . 16...................................10 Appendix A. Metricsrepresented using RFC6390Represented Using the Template. . . . . 18 Appendix B. Change Log . . . . . . . . . . . . . . . . . . . . . 21 B.1. draft-ietf-xrblock-rtcp-xr-burst-gap-discard-14 . . . . . 21 B.2. draft-ietf-xrblock-rtcp-xr-burst-gap-discard-13 . . . . . 21 B.3. draft-ietf-xrblock-rtcp-xr-burst-gap-discard-12 . . . . . 21 B.4. draft-ietf-xrblock-rtcp-xr-burst-gap-discard-11 . . . . . 21 B.5. draft-ietf-xrblock-rtcp-xr-burst-gap-discard-10 . . . . . 21 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 22from RFC 6390..12 1. Introduction 1.1.Burst and GapBurst/Gap DiscardReportMetrics 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 discarded by the jitter buffer at the receiver, using packet discard logic according to the jitter buffer algorithms. The discards during discard bursts are reported, together with the number of bursts. This block is intended to be used in conjunction with[DISCARD][RFC7002], which provides the total packetsdiscarded,discarded and on which this block therefore depends.HoweverHowever, the metric in[DISCARD][RFC7002] may be used independently of the metrics in this block. This block provides information on transient IP problems.Burst/GapBurst/gap metrics are typically used in cumulativereports, howeverreports; however, they also may be used in interval reports (see the Interval Metric flag insectionSection 3.2). The burstiness of packet discard 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-relatedend systemend-system metrics defined in [RFC6792]. The definitions ofBurst, Gap, Loss"burst", "gap", "loss", andDiscard"discard" are consistent with the 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 shall use an equivalent method to that defined inthe sectionSection 4.7.2 of [RFC3611]. Note thatReportingreporting the specific jitter buffer algorithms and/or packet discard logic is out of the scope of this document. 1.2. RTCP and RTCPXRExtended 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 MonitoringArchitecturesFramework [RFC6792] providesguidelineguidelines for reporting block format using RTCP XR. The metrics block described in this documentareis in accordance with the guidelines in [RFC6390] and [RFC6792]. 1.4. Applicability These metrics are applicable to a range of RTP applicationswhichthat contain de-jitter buffers [RFC5481] at the receiving end to smooth variation inpacket arrivingpacket-arrival time and don't use stream repair means, e.g., Forward Error Correction (FEC) [RFC5109] and/or retransmission [RFC4588]. 2. Terminology2.1. Standards LanguageThe 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,LostLost, and Discarded A packet shall be regarded aslost"lost" if it fails to arrive within an implementation-specific time window. A packet that arrives within this time window but iseithertoo early to be playedout orout, too late to be playedoutout, or thrown away before playout due to packet duplication or redundancy shall be regarded as discarded. A packet shall not be regarded as discarded if it arrives within this time window but is dropped during decoding by somehigherhigher- layer decoder, e.g., due to a decoding error. A packet shall be classified as one of received (or OK),discardeddiscarded, or lost. The metric "cumulative number of packets lost" defined in [RFC3550] reports a count of packets lost from the media stream (singleSSRCsynchronization source (SSRC) within a single RTP session).SimilarlySimilarly, the metric "number of packets discarded" defined in[DISCARD][RFC7002] reports a count of packets discarded from the media stream (single SSRC within a single RTP session) arriving at the receiver. Anothermetricmetric, defined in[RFC5725][RFC5725], is available to report on packetswhichthat are not recovered by any repair techniqueswhichthat may be in use. Note that the termdiscard"discard" defined herebuildbuilds on theDiscard"discard" definition[RFC3611],in [RFC3611] butextendextends the concept to take into accountthepacketduplication,duplication andreportreports different types of discard counts[DISCARD].[RFC7002]. Bursts and Gaps The termsBurst"burst" andGap"gap" are used in a manner consistent with that of RTCP XR [RFC3611]. RTCP XR viewsaan RTP stream as being divided into bursts, which are periods during which the discard rate is high enough to cause noticeable quality degradation (generally over 5 percent discard rate), and gaps, which are periods during which discarded packets are infrequent and hence quality is generally acceptable. 3. Burst/Gap Discard Metrics Block Metrics in this block report onBurst/Gap Discardburst/gap discard in the stream arriving at the RTP system.The measurementMeasurements of these metrics are made at the receiving end of the RTP stream. Instances of this metrics blockrefer by Synchronizationuse the synchronization source (SSRC) to refer to the separate auxiliary Measurement Information Block[RFC6776][RFC6776], which describes measurement periods in use (seeRFC6776 section[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 The structure of the Burst/Gap Discard Metrics Block is as follows. 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=NBGDBT=20 | I |resv.resv |block lengthBlock Length = 3 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | SSRC of Source | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Threshold | Packets Discarded in Bursts | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Total PacketsexpectedExpected in Bursts |Reserved.Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 1: Report Block Structure 3.2. Definition of Fields in Burst/Gap DiscardReportMetrics Block BlocktypeType (BT): 8 bits A Burst/Gap DiscardReportMetrics Block is identified by the constantNBGD. [Note to RFC Editor: please replace NBGD with the IANA provided RTCP XR block type for this block.]20. Interval Metric flag (I): 2 bits This field is used to indicate whether theBurst/Gap Discardburst/gap discard metrics are Sampled,IntervalInterval, or Cumulative metrics [RFC6792]: 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 Discard Metricsburst/gap discard metrics can only be measured over definiteintervals,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. Reserved (resv): 6 bits These bits are reserved. They MUST be set to zero by senders and ignored by receivers(See RFC6709 section(see [RFC6709], Section 4.2).block length:Block Length: 16 bits The length of this report block in 32-bit words, minus one. For the Burst/Gapdiscard block,Discard Metrics Block, the block length is equal to 3. The block MUST be discarded if the block length is set to a different value. SSRC ofsource:Source: 32 bits As defined in Section 4.1 of [RFC3611]. Threshold: 8 bits The Threshold is equivalent to Gmin in [RFC3611],i.e.i.e., the number of successive packets that must not be discarded prior to and following a discard packet in order for this discarded packet to be regarded as part of a gap. Note that thethresholdThreshold is set in accordance with the GminCalculationcalculation defined insectionSection 4.7.2 ofRFC3611.[RFC3611]. PacketsdiscardedDiscarded inbursts:Bursts: 24 bits The total number of packets discarded during discard 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. Totalpackets expectedPackets Expected inbursts:Bursts: 24 bits The total number of packets expected duringdiscardeddiscard 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.Reserved (resv):Reserved: 8 bits These bits are reserved. They MUST be set to zero by senders and ignored by receivers (SeeRFC6709 section[RFC6709], Section 4.2). 3.3. Derivedmetrics basedMetrics Based onreported metricsReported Metrics The metrics described here are intended to be used in conjunction with information from the Measurement Information Block [RFC6776] and also with the metric "number of packets discarded" provided in the RTCP XR Discard Count Metrics Block[DISCARD].[RFC7002]. These metrics provide the following information relevant to statistical parameters, including: o The fraction of packets discarded during bursts(burst discard rate(Burst Discard Rate in[SUMSTAT]),[RFC7004]), which can be calculated using the metric" Packets"Packets Discarded inBursts "Bursts" and the metric" Total"Total PacketsexpectedExpected inBursts "Bursts" provided in the Burst/Gap Discard Metrics Block. o The fraction of packets discarded during gaps(gap discard rate(Gap Discard Rate in[SUMSTAT]),[RFC7004]), which can be calculated using the metric" Packets"Packets Discarded inBursts "Bursts" and the metric" Total"Total PacketsexpectedExpected inBursts "Bursts" provided in the Burst/Gap Discard Metrics Block. The details on calculation these parameters in the metrics are described in[SUMSTAT].[RFC7004]. 4. Considerations for Voice-over-IPapplicationsApplications This metrics block is applicable to a broad range of RTP applications. Where the metric is used with aVoice over IPVoice-over-IP (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 discard rate is high enough to cause noticeable call quality degradation (generally over 5 percent discardrate),rate) and gaps, which are periods during which discarded packets are infrequent and hence call quality is generally acceptable. If voice activity detection is used, theBurstburst andGap Durationgap duration shall be determined as if silence packets had been sent,i.e.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 aBurstburst being a period of time during which the call quality is degraded to a similar extent to a typicalpulse-code modulation(PCM)pulse code modulation (PCM) severely errored second. 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. SDPrtcp-xr-attribrtcp-xr 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. The ABNF [RFC5234] syntax is as follows. xr-format =/ xr-bgd-block xr-bgd-block = "burst-gap-discard" 5.2. Offer/Answer Usage When SDP is used inoffer-answerOffer/Answer context, the SDP Offer/Answer usage defined in [RFC3611] for unilateral "rtcp-xr" attribute parameters applies. For detailed usage in Offer/Answer for unilateralparameter,parameters, refer tosectionSection 5.2 of [RFC3611]. 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 TypevalueValue This document assigns the block type valueNBGD20 in the IANA" RTP"RTP Control Protocol Extended Reports (RTCP XR) Block TypeRegistry "Registry" to the "Burst/Gap Discard Metrics Block".[Note to RFC Editor: please replace NBGD 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-discard" in the "RTP Control Protocol Extended Reports (RTCP XR) Session Description Protocol (SDP) Parameters Registry". 6.3. ContactinformationInformation forregistrationsRegistrations The contact information for the registrations is: Qin Wu (sunseawq@huawei.com) 101 Software Avenue, Yuhua District Nanjing, Jiangsu 210012 China 7. Security Considerations It is believed that thisproposedRTCP XRreportblock introduces no new security considerations beyond those described in [RFC3611]. This block does not provide per-packetstatisticsstatistics, so the risk to confidentiality documented in Section 7, paragraph 3 of [RFC3611] does not apply. 8. Contributors Geoff Hunt wrote the initial draft of this document. 9. Acknowledgments The authors gratefully acknowledge reviews and feedback provided by Bruce Adams, Philip Arden, Amit Arora, Claire Bi, Bob Biskner, Benoit Claise, Kevin Connor, Claus Dahm, Randy Ethier, Roni Even, Stephen Farrell, Jim Frauenthal, Albert Higashi, Tom Hock, Shane Holthaus, Paul Jones, Rajesh Kumar, Paul Kyzivat, Keith Lantz, Mohamed Mostafa, Amy Pendleton, Colin Perkins, Mike Ramalho, Ravi Raviraj, Dan Romascanu, Albrecht Schwarz, Tom Taylor,Hideaki Yamada, Paul Kyzivat,Claire Bi,Stephen Farrell, Benoit ClaiseandDan Romascanu.Hideaki Yamada. 10. References 10.1. Normative References[DISCARD] Wu, Q., "RTCP XR Report Block for Discard Count metric Reporting", ID draft-ietf-xrblock-rtcp-xr-discard-11, December 2012.[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC3550] Schulzrinne, H., Casner, S., Frederick, R., and V. 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 Protocol Extended Reports (RTCP XR)", RFC 3611, November 2003. [RFC4566] Handley, M., Jacobson, V., and C. Perkins, "SDP: Session Description Protocol", RFC 4566, July 2006. [RFC5234] Crocker, D. and P. Overell, "Augmented BNF for Syntax Specifications: ABNF", STD 68, RFC 5234, January 2008. [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, February2020.2010. [RFC6776] Clark, A. and Q. Wu,Q.,"Measurement Identity andinformationInformation Reportingusing SDES itemUsing a Source Description (SDES) Item andXRan RTCP Extended Report (XR) Block", RFC 6776, October 2012.[SUMSTAT][RFC7002] Clark, A., Zorn, G.,"RTCP XRand Q. Wu, "RTP Control Protocol (RTCP) Extended Report (XR) for Discard Count Metric Reporting", RFC 7002, August 2013. [RFC7004] Zorn, G., Schott, R., Wu, Q., Ed., and R. Huang, "RTP Control Protocol (RTCP) Extended Report (XR) Blocks for Summary Statistics Metrics Reporting",ID draft-ietf-xrblock-rtcp-xr-summary-stat-11, MarchRFC 7004, August 2013. 10.2. Informative References [RFC4588] Rey, J., Leon, D.,,Miyazaki, 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. [RFC5481] Morton, A. and B. Claise, "Packet Delay Variation Applicability Statement", RFC 5481, March 2009. [RFC6390] Clark, A. and B. Claise,"Framework"Guidelines for Considering New Performance Metric Development", BCP 170, RFC 6390, October 2011. [RFC6709] Carpenter, B., Aboba, B., and S. Cheshire, "Design Considerations for Protocol Extensions", RFC 6709, September 2012. [RFC6792] Wu, Q., Hunt, G.,"Monitoring Architecturesand P. Arden, "Guidelines forRTP",Use of the RTP Monitoring Framework", RFC 6792, November 2012. Appendix A. Metricsrepresented using RFC6390 Template RFC EDITOR NOTE: please change XXXX in [RFCXXXX] byRepresented Using thenewTemplate from RFCnumber, when assigned.6390 a. Burst/Gap Discard Threshold in RTP Metric * Metric Name:ThresholdBurst/gap discard threshold in RTP * Metric Description: The Threshold is equivalent to Gmin in [RFC3611],i.e.i.e., the number of successive packets that must not be discarded prior to and following a discard packet in order for this discarded packet to be regarded as part of a gap. * Method of Measurement or Calculation: SeesectionSection 3.2, Thresholddefinition [RFCXXXX].definition. * Units of Measurement: SeesectionSection 3.2, Thresholddefinition [RFCXXXX].definition. * Measurement Point(s) with Potential Measurement Domain: SeesectionSection 3, 1stparagraph [RFCXXXX].paragraph. * Measurement Timing: SeesectionSection 3, 2nd paragraph[RFCXXXX]for measurement timing andsectionSection 3.2[RFCXXXX]for Interval Metric flag. * Use andapplications:Applications: Seesection 1.4 [RFCXXXX].Section 1.4. * Reportingmodel:Model: SeeRFC3611.RFC 3611. b. PacketsdiscardedDiscarded inburstsBursts Metric * Metric Name: RTPPacketspackets discarded in bursts * Metric Description: The total number of RTP packets discarded during discard bursts. * Method of Measurement or Calculation: SeesectionSection 3.2, PacketsdiscardedDiscarded inbursts definition [RFCXXXX].Bursts definition. * Units of Measurement: SeesectionSection 3.2, PacketsdiscardedDiscarded inbursts definition [RFCXXXX].Bursts definition. * Measurement Point(s) with Potential Measurement Domain: SeesectionSection 3, 1stparagraph [RFCXXXX].paragraph. * Measurement Timing: SeesectionSection 3, 2nd paragraph[RFCXXXX]for measurement timing andsectionSection 3.2[RFCXXXX]for Interval Metric flag. * Use andapplications:Applications: Seesection 1.4 [RFCXXXX].Section 1.4. * Reportingmodel:Model: SeeRFC3611.RFC 3611. c. Totalpackets expectedPackets Expected inburstsDiscard Bursts Metric * Metric Name: Total RTP packets expected in discard bursts * Metric Description: The total number of packets expected duringdiscardeddiscard bursts (that is, the sum of received packets and lost packets). * Method of Measurement or Calculation: SeesectionSection 3.2, Totalpackets expectedPackets Expected inbursts definition [RFCXXXX].Bursts definition. * Units of Measurement: SeesectionSection 3.2, Totalpackets expectedPackets Expected inbursts definition [RFCXXXX].Bursts definition. * Measurement Point(s) with Potential Measurement Domain: SeesectionSection 3, 1stparagraph [RFCXXXX].paragraph. * Measurement Timing: SeesectionSection 3, 2nd paragraph[RFCXXXX]for measurement timing andsectionSection 3.2[RFCXXXX]for Interval Metric flag. * Use andapplications:Applications: Seesection 1.4 [RFCXXXX].Section 1.4. * Reportingmodel:Model: SeeRFC3611. 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-discard-14 The following are the major changes compared to previous version: o Editorial changes to address comments raised in IESG review and other Directorate review. B.2. draft-ietf-xrblock-rtcp-xr-burst-gap-discard-13 The following are the major changes compared to previous version: o Additional editorial changes to Burst Gap discard draft to get in line with Burst Gap Loss draft. B.3. draft-ietf-xrblock-rtcp-xr-burst-gap-discard-12 The following are the major changes compared to previous version: o Similar changes to Burst Gap loss draft to get in line with Burst Gap Loss draft. B.4. draft-ietf-xrblock-rtcp-xr-burst-gap-discard-11 The following are the major changes compared to previous version: o Similar changes to Burst Gap loss draft to address IESG review comments apply to this document. B.5. draft-ietf-xrblock-rtcp-xr-burst-gap-discard-10 The following are the major changes compared to previous version: o Move RFC6709 as one informative reference.RFC 3611. Authors' Addresses Alan Clark Telchemy Incorporated 2905 Premiere Parkway, Suite 280 Duluth, GA 30097 USAEmail:EMail: alan.d.clark@telchemy.com Rachel Huang Huawei Technologies Co., Ltd. 101 Software Avenue, Yuhua District Nanjing, Jiangsu 210012 ChinaEmail:EMail: Rachel@huawei.com Qin Wu (editor) Huawei 101 Software Avenue, Yuhua District Nanjing, Jiangsu 210012 ChinaEmail:EMail: sunseawq@huawei.com