idnits 2.17.1 draft-ietf-xrblock-rtcp-xr-burst-gap-loss-10.txt: Checking boilerplate required by RFC 5378 and the IETF Trust (see https://trustee.ietf.org/license-info): ---------------------------------------------------------------------------- No issues found here. Checking nits according to https://www.ietf.org/id-info/1id-guidelines.txt: ---------------------------------------------------------------------------- No issues found here. Checking nits according to https://www.ietf.org/id-info/checklist : ---------------------------------------------------------------------------- No issues found here. Miscellaneous warnings: ---------------------------------------------------------------------------- == The copyright year in the IETF Trust and authors Copyright Line does not match the current year -- The document date (April 11, 2013) is 4033 days in the past. Is this intentional? Checking references for intended status: Proposed Standard ---------------------------------------------------------------------------- (See RFCs 3967 and 4897 for information about using normative references to lower-maturity documents in RFCs) == Missing Reference: 'RFCXXXX' is mentioned on line 669, but not defined == Unused Reference: 'RFC6709' is defined on line 506, but no explicit reference was found in the text ** Obsolete normative reference: RFC 4566 (Obsoleted by RFC 8866) == Outdated reference: A later version (-15) exists of draft-ietf-xrblock-rtcp-xr-discard-11 Summary: 1 error (**), 0 flaws (~~), 4 warnings (==), 1 comment (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Audio/Video Transport Working Group A. Clark 3 Internet-Draft Telchemy 4 Intended status: Standards Track S. Zhang 5 Expires: October 13, 2013 J. Zhao 6 STTRI 7 Q. Wu, Ed. 8 Huawei 9 April 11, 2013 11 RTP Control Protocol (RTCP) Extended Report (XR) Block for Burst/Gap 12 Loss metric Reporting 13 draft-ietf-xrblock-rtcp-xr-burst-gap-loss-10.txt 15 Abstract 17 This document defines an RTP Control Protocol (RTCP) Extended Report 18 (XR) Block that allows the reporting of Burst and Gap Loss metrics 19 for use in a range of RTP applications. 21 Status of this Memo 23 This Internet-Draft is submitted in full conformance with the 24 provisions of BCP 78 and BCP 79. 26 Internet-Drafts are working documents of the Internet Engineering 27 Task Force (IETF). Note that other groups may also distribute 28 working documents as Internet-Drafts. The list of current Internet- 29 Drafts is at http://datatracker.ietf.org/drafts/current/. 31 Internet-Drafts are draft documents valid for a maximum of six months 32 and may be updated, replaced, or obsoleted by other documents at any 33 time. It is inappropriate to use Internet-Drafts as reference 34 material or to cite them other than as "work in progress." 36 This Internet-Draft will expire on October 13, 2013. 38 Copyright Notice 40 Copyright (c) 2013 IETF Trust and the persons identified as the 41 document authors. All rights reserved. 43 This document is subject to BCP 78 and the IETF Trust's Legal 44 Provisions Relating to IETF Documents 45 (http://trustee.ietf.org/license-info) in effect on the date of 46 publication of this document. Please review these documents 47 carefully, as they describe your rights and restrictions with respect 48 to this document. Code Components extracted from this document must 49 include Simplified BSD License text as described in Section 4.e of 50 the Trust Legal Provisions and are provided without warranty as 51 described in the Simplified BSD License. 53 Table of Contents 55 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 56 1.1. Burst and Gap Loss Report Block . . . . . . . . . . . . . 3 57 1.2. RTCP and RTCP XR Reports . . . . . . . . . . . . . . . . . 3 58 1.3. Performance Metrics Framework . . . . . . . . . . . . . . 3 59 1.4. Applicability . . . . . . . . . . . . . . . . . . . . . . 4 60 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 5 61 2.1. Standards Language . . . . . . . . . . . . . . . . . . . . 5 62 3. Burst/Gap Loss Block . . . . . . . . . . . . . . . . . . . . . 6 63 3.1. Report Block Structure . . . . . . . . . . . . . . . . . . 6 64 3.2. Definition of Fields in Burst/Gap Loss Report Block . . . 6 65 3.3. Derived metrics based on reported metrics . . . . . . . . 9 66 4. Considerations for Voice-over-IP applications . . . . . . . . 11 67 5. SDP Signaling . . . . . . . . . . . . . . . . . . . . . . . . 12 68 5.1. SDP rtcp-xr-attrib Attribute Extension . . . . . . . . . . 12 69 5.2. Offer/Answer Usage . . . . . . . . . . . . . . . . . . . . 12 70 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13 71 6.1. New RTCP XR Block Type value . . . . . . . . . . . . . . . 13 72 6.2. New RTCP XR SDP Parameter . . . . . . . . . . . . . . . . 13 73 6.3. Contact information for registrations . . . . . . . . . . 13 74 7. Security Considerations . . . . . . . . . . . . . . . . . . . 14 75 8. Contributors . . . . . . . . . . . . . . . . . . . . . . . . . 15 76 9. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 16 77 10. References . . . . . . . . . . . . . . . . . . . . . . . . . . 17 78 10.1. Normative References . . . . . . . . . . . . . . . . . . . 17 79 10.2. Informative References . . . . . . . . . . . . . . . . . . 17 80 Appendix A. Metrics represented using RFC6390 Template . . . . . 18 81 Appendix B. Change Log . . . . . . . . . . . . . . . . . . . . . 23 82 B.1. draft-ietf-xrblock-rtcp-xr-burst-gap-loss-10 . . . . . . . 23 83 B.2. draft-ietf-xrblock-rtcp-xr-burst-gap-loss-09 . . . . . . . 23 84 B.3. draft-ietf-xrblock-rtcp-xr-burst-gap-loss-08 . . . . . . . 23 85 B.4. draft-ietf-xrblock-rtcp-xr-burst-gap-loss-07 . . . . . . . 23 86 B.5. draft-ietf-xrblock-rtcp-xr-burst-gap-loss-06 . . . . . . . 23 87 B.6. draft-ietf-xrblock-rtcp-xr-burst-gap-loss-04 . . . . . . . 23 88 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 24 90 1. Introduction 92 1.1. Burst and Gap Loss Report Block 94 This document defines a new block type to augment those defined in 95 [RFC3611] for use in a range of RTP applications. The new block type 96 supports the reporting of the proportion of packets lost by the 97 network. The losses during loss bursts are reported, together with 98 the number of bursts and additional data allowing the calculation of 99 statistical parameters (mean and variance) of the distribution of 100 burst lengths. Some uses of these metrics depend on the availability 101 of the metric "cumulative number of packets lost" from RTCP 102 [RFC3550]. 104 This block provides information on transient IP problems. Burst/Gap 105 metrics are typically used in Cumulative reports, however they also 106 MAY be used in Interval reports. The burstiness of packet loss 107 affects user experience, may influence any sender strategies to 108 mitigate the problem, and may also have diagnostic value. 110 The metric belongs to the class of transport-related end system 111 metrics defined in [RFC6792]. 113 The definitions of Burst, Gap, Loss and Discard are consistent with 114 definitions in [RFC3611]. To accommodate the range of jitter buffer 115 algorithms and packet discard logic that may be used by implementors, 116 the method used to distinguish between bursts and gaps may be an 117 equivalent method to that defined in [RFC3611]. The method used 118 should produce the same result as that defined in [RFC3611] for 119 conditions of burst packet loss, but may produce different results 120 for conditions of time varying jitter. 122 1.2. RTCP and RTCP XR Reports 124 The use of RTCP for reporting is defined in [RFC3550]. [RFC3611] 125 defined an extensible structure for reporting using an RTCP Extended 126 Report (XR). This document defines a new Extended Report block for 127 use with [RFC3550] and [RFC3611]. 129 1.3. Performance Metrics Framework 131 The Performance Metrics Framework [RFC6390] provides guidance on the 132 definition and specification of performance metrics. The RTP 133 Monitoring Architectures [RFC6792] provides guideline for reporting 134 block format using RTCP XR. The Metrics Block described in this 135 document are in accordance with the guidelines in [RFC6390] and 136 [RFC6792]. 138 1.4. Applicability 140 These metrics are applicable to a range of RTP applications which 141 contain jitter buffers and don't use stream repair means, e.g., 142 Forward Error Correction (FEC) [RFC5109] and/or retransmission 143 [RFC4588]. 145 2. Terminology 147 2.1. Standards Language 149 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 150 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 151 document are to be interpreted as described in RFC 2119 [RFC2119]. 153 In addition, the following terms are defined: 155 Received, Lost and Discarded 157 A packet shall be regarded as lost if it fails to arrive within an 158 implementation-specific time window. A packet that arrives within 159 this time window but is too early or late to be played out or 160 thrown away before playout due to packet duplication or redundancy 161 shall be regarded as discarded. A packet shall be classified as 162 one of received (or OK), discarded or lost. The metric 163 "cumulative number of packets lost" defined in [RFC3550] reports a 164 count of packets lost from the media stream (single SSRC within 165 single RTP session). Similarly the metric "number of packets 166 discarded" defined in [DISCARD] reports a count of packets 167 discarded from the media stream (single SSRC within single RTP 168 session) arriving at the receiver. Another metric defined in 169 [RFC5725] is available to report on packets which are not 170 recovered by any repair techniques which may be in use. 172 Bursts and Gaps 174 The terms Burst and Gap are used in a manner consistent with that 175 of RTCP XR [RFC3611]. RTCP XR views a RTP stream as being divided 176 into bursts, which are periods during which the loss rate is high 177 enough to cause noticeable quality degradation (generally over 5 178 percent loss rate), and gaps, which are periods during which lost 179 packets are infrequent and hence quality is generally acceptable. 181 3. Burst/Gap Loss Block 183 Metrics in this block report on Burst/Gap Loss in the stream arriving 184 at the RTP system. The measurement of these metrics are made at the 185 receiving end of the RTP stream. Instances of this Metrics Block 186 refer by Synchronization source (SSRC) to the separate auxiliary 187 Measurement Information block [RFC6776] which describes measurement 188 periods in use(see RFC6776 section 4.2). This Metrics Block relies 189 on the measurement period in the Measurement Information block 190 indicating the span of the report and MUST be sent in the same 191 compound RTCP packet as the measurement information block. If the 192 measurement period is not received in the same compound RTCP packet 193 as this Metrics Block, this Metrics Block MUST be discarded. 195 3.1. Report Block Structure 197 Burst/Gap Loss metrics block 199 0 1 2 3 200 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 1 201 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 202 | BT=NBGL | I |C| resv. | block length = 5 | 203 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 204 | SSRC of Source | 205 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 206 | Threshold | Sum of Burst Durations (ms) | 207 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 208 | Packets Lost in Bursts | Total... | 209 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 210 | ...Packets expected in bursts | Number of bursts | Sum of| 211 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 212 | ...Squares of Burst Durations (ms-squared) | 213 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 215 Figure 1: Report Block Structure 217 3.2. Definition of Fields in Burst/Gap Loss Report Block 219 Block type (BT): 8 bits 221 A Burst/Gap Loss Report Block is identified by the constant NBGL. 223 [Note to RFC Editor: please replace NBGL with the IANA provided 224 RTCP XR block type for this block.] 226 Interval Metric flag (I): 2 bits 228 This field is used to indicate whether the Burst/Gap Loss metrics 229 are Sampled, Interval or Cumulative metrics: 231 I=10: Interval Duration - the reported value applies to the 232 most recent measurement interval duration between successive 233 metrics reports. 235 I=11: Cumulative Duration - the reported value applies to the 236 accumulation period characteristic of cumulative measurements. 238 I=01: Sampled Value - the reported value is a sampled 239 instantaneous value. 241 In this document, Burst/Gap Loss Metrics can only be measured over 242 definite intervals, and cannot be sampled. Accordingly, the value 243 I=01, indicating a sampled value, MUST NOT be sent, and MUST be 244 discarded when received. In addition, the value I=00 is reserved 245 and also MUST NOT be sent, and MUST be discarded when received. 247 Loss and Discard Combination flag (C): 1 bit 249 The 'C' flag is used to indicate whether the loss/discard report 250 is combined with the burst gap loss report in the same compound 251 RTCP packet. The value is set to '1' if the loss/discard report 252 and the burst gap loss report are combined. Otherwise, the value 253 is set to '0'. If the 'C' flag is set to 1 but the burst gap 254 discard was not sent, the receiver MUST discard the burst gap 255 loss. 257 Reserved (resv): 5 bits 259 These bits are reserved. They MUST be set to zero by senders and 260 ignored by receivers (See RFC6709 section 4.2). 262 block length: 16 bits 264 The length of this report block in 32-bit words, minus one. For 265 the Burst/Gap Loss block, the block length is equal to 5. The 266 block MUST be discarded if the block length is set to a different 267 value. 269 SSRC of source: 32 bits 271 As defined in Section 4.1 of [RFC3611]. 273 Threshold: 8 bits 275 The Threshold is equivalent to Gmin in [RFC3611], i.e. the number 276 of successive packets that must be received prior to and following 277 a lost packet in order for this lost packet to be regarded as part 278 of a gap. Note that the threshold is calculated in accordance 279 with Gmin Calculation defined in section 4.7.2 of RFC3611. 281 Sum of Burst Durations (ms): 24 bits 283 The total duration of bursts of lost packets in the period of the 284 report (Interval or Cumulative). 286 The measured value is unsigned value. If the measured value 287 exceeds 0xFFFFFD, the value 0xFFFFFE MUST be reported to indicate 288 an over-range measurement. If the measurement is unavailable, the 289 value 0xFFFFFF MUST be reported. 291 Packets lost in bursts: 24 bits 293 The total number of packets lost during loss bursts. 295 The measured value is unsigned value. If the measured value 296 exceeds 0xFFFFFD, the value 0xFFFFFE MUST be reported to indicate 297 an over-range measurement. If the measurement is unavailable, the 298 value 0xFFFFFF MUST be reported. 300 Total packets expected in bursts: 24 bits 302 The total number of packets expected during loss bursts (that is, 303 the sum of received packets and lost packets). 305 The measured value is unsigned value. If the measured value 306 exceeds 0xFFFFFD, the value 0xFFFFFE MUST be reported to indicate 307 an over-range measurement. If the measurement is unavailable, the 308 value 0xFFFFFF MUST be reported. 310 Number of bursts: 16 bits 312 The number of bursts in the period of the report (Interval or 313 Cumulative). 315 The measured value is unsigned value. If the measured value 316 exceeds 0xFFFD, the value 0xFFFE MUST be reported to indicate an 317 over-range measurement. If the measurement is unavailable, the 318 value 0xFFFF MUST be reported. 320 Sum of Squares of Burst Durations (ms-squared): 36 bits 322 The sum of the squares of burst durations (where individual burst 323 durations are expressed in ms) over in the period of the report 324 (Interval or Cumulative). The units for this quantity are 325 milliseconds-squared. 327 The measured value is unsigned value. If the measured value 328 exceeds 0xFFFFFFFFD, the value 0xFFFFFFFFE MUST be reported to 329 indicate an over-range measurement. If the measurement is 330 unavailable, the value 0xFFFFFFFFF MUST be reported. 332 3.3. Derived metrics based on reported metrics 334 The metrics described here are intended to be used as described in 335 this section, in conjunction with information from the Measurement 336 Information block [RFC6776] (which MUST be present in the same RTCP 337 packet as the Burst/Gap Loss block (see section 3,1st paragraph) ) 338 and also with the metric "cumulative number of packets lost" provided 339 in standard RTCP [RFC3550]. 341 These metrics provide information relevant to statistical parameters, 342 including: 344 o The fraction of packets lost during bursts (i.e., Burst Loss Rate 345 in [SUMSTAT]), which can be calculated using the metric " Packets 346 Loss in Bursts " and the metric " Total Packets expected in Bursts 347 " provided in the Burst/Gap Loss metrics block. 349 o The fraction of packets lost during gaps (i.e., Gap Loss Rate in 350 [SUMSTAT]), which can be calculated using the metric " Packets 351 Loss in Bursts " and the metric " Total Packets expected in Bursts 352 " provided in the Burst/Gap Loss metrics block. 354 o burst duration mean [SUMSTAT], which can be calculated using the 355 metric " Packets Loss in Bursts " and the metric " Total Packets 356 expected in Bursts " provided in the Burst/Gap Loss metrics block. 358 o burst duration variance [SUMSTAT], which can be calculated using 359 the metric " Packets Loss in Bursts " and the metric " Total 360 Packets expected in Bursts " provided in the Burst/Gap Loss 361 metrics block. 363 The details on calculation these parameters in the metrics are 364 described in [SUMSTAT]. 366 4. Considerations for Voice-over-IP applications 368 This Metrics Block is applicable to a broad range of RTP 369 applications. Where the metric is used with a Voice-overIP (VoIP) 370 application and the stream repair means is not available, the 371 following considerations apply. 373 RTCP XR views a call as being divided into bursts, which are periods 374 during which the loss rate is high enough to cause noticeable call 375 quality degradation (generally over 5 percent loss rate), and gaps, 376 which are periods during which lost packets are infrequent and hence 377 call quality is generally acceptable. 379 If Voice Activity Detection is used the Burst and Gap Duration shall 380 be determined as if silence packets had been sent, i.e. a period of 381 silence in excess of Gmin packets must terminate a burst condition. 383 The recommended value for the threshold Gmin in [RFC3611] results in 384 a Burst being a period of time during which the call quality is 385 degraded to a similar extent to a typical Pulse-Code Modulation(PCM) 386 Severely Errored Second. 388 5. SDP Signaling 390 [RFC3611] defines the use of SDP (Session Description Protocol) 391 [RFC4566] for signaling the use of XR blocks. XR blocks MAY be used 392 without prior signaling. 394 5.1. SDP rtcp-xr-attrib Attribute Extension 396 This section augments the SDP [RFC4566] attribute "rtcp-xr" defined 397 in [RFC3611] by providing an additional value of "xr-format" to 398 signal the use of the report block defined in this document. 400 xr-format =/ xr-bgl-block 402 xr-bgl-block = "burst-gap-loss" 404 5.2. Offer/Answer Usage 406 When SDP is used in offer-answer context, the SDP Offer/Answer usage 407 defined in [RFC3611] for unilateral "rtcp-xr" attribute parameters 408 applies. For detailed usage in Offer/Answer for unilateral 409 parameter, refer to section 5.2 of [RFC3611]. 411 6. IANA Considerations 413 New block types for RTCP XR are subject to IANA registration. For 414 general guidelines on IANA considerations for RTCP XR, refer to 415 [RFC3611]. 417 6.1. New RTCP XR Block Type value 419 This document assigns the block type value NBGL in the IANA " RTP 420 Control Protocol Extended Reports (RTCP XR) Block Type Registry " to 421 the "Burst/Gap Loss Metrics Block". 423 [Note to RFC Editor: please replace NBGL with the IANA provided RTCP 424 XR block type for this block.] 426 6.2. New RTCP XR SDP Parameter 428 This document also registers a new parameter "burst-gap-loss" in the 429 " RTP Control Protocol Extended Reports (RTCP XR) Session Description 430 Protocol (SDP) Parameters Registry". 432 6.3. Contact information for registrations 434 The contact information for the registrations is: 436 Qin Wu (sunseawq@huawei.com) 438 101 Software Avenue, Yuhua District 439 Nanjing, Jiangsu 210012 440 China 442 7. Security Considerations 444 This block does not provide per-packet statistics, so the risk to 445 confidentiality documented in Section 7, paragraph 3 of [RFC3611] 446 does not apply. However the gaps indicated within this block could 447 be used to detect the timing of other events on the path between the 448 sender and receiver. For example, a competing multimedia stream 449 might cause a loss burst for the duration of the stream, allowing the 450 receiver of this block to know when the competing stream was active. 451 This risk is not a significant threat since the only information 452 leaked is the timing of the loss, not the cause. Besides this, it is 453 believed that this proposed RTCP XR report block introduces no other 454 new security considerations beyond those described in [RFC3611]. 456 8. Contributors 458 Geoff Hunt wrote the initial draft of this document. 460 9. Acknowledgments 462 The authors gratefully acknowledge reviews and feedback provided by 463 Bruce Adams, Philip Arden, Amit Arora, Bob Biskner, Kevin Connor, 464 Claus Dahm, Randy Ethier, Roni Even, Jim Frauenthal, Albert Higashi, 465 Tom Hock, Shane Holthaus, Paul Jones, Rajesh Kumar, Keith Lantz, 466 Mohamed Mostafa, Amy Pendleton, Colin Perkins, Mike Ramalho, Ravi 467 Raviraj, Albrecht Schwarz, Tom Taylor, Hideaki Yamada, Adam Roach, 468 Dan Romascanu,Chris Lonvick, Alfred C.,Morton Jr., Pete Resnick, Ted 469 Lemon, Stephen Farrell, Richard Barnes, Benoit Claise. 471 10. References 473 10.1. Normative References 475 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 476 Requirement Levels", March 1997. 478 [RFC3550] Schulzrinne, H., "RTP: A Transport Protocol for Real-Time 479 Applications", RFC 3550, July 2003. 481 [RFC3611] Friedman, T., Caceres, R., and A. Clark, "RTP Control 482 Protocol Extended Reports (RTCP XR)", November 2003. 484 [RFC4566] Handley, M., Jacobson, V., and C. Perkins, "SDP: Session 485 Description Protocol", July 2006. 487 [RFC5725] Begen, A., Hsu, D., and M. Lague, "Post-Repair Loss RLE 488 Report Block Type for RTP Control Protocol (RTCP) Extended 489 Reports (XRs)", RFC 5725, February 2020. 491 10.2. Informative References 493 [DISCARD] Wu, Q., "RTCP XR Report Block for Discard metric 494 Reporting", ID draft-ietf-xrblock-rtcp-xr-discard-11, 495 December 2012. 497 [RFC4588] Rey, J., Leon, D., , A., Varsa, V., and R. Hakenberg, "RTP 498 Retransmission Payload Format", RFC 4588, July 2006. 500 [RFC5109] Li, A., "RTP Payload Format for Generic Forward Error 501 Correction", RFC 5109, December 2007. 503 [RFC6390] Clark, A. and B. Claise, "Framework for Performance Metric 504 Development", RFC 6390, July 2011. 506 [RFC6709] Carpenter, B., Aboba, B., and S. Cheshire, "Design 507 Considerations for Protocol Extensions", RFC 6709, 508 September 2012. 510 [RFC6776] Wu, Q., "Measurement Identity and information Reporting 511 using SDES item and XR Block", RFC 6776, October 2012. 513 [RFC6792] Hunt, G., "Monitoring Architectures for RTP", RFC 6792, 514 November 2012. 516 [SUMSTAT] Zorn, G., "RTCP XR for Summary Statistics Metrics 517 Reporting", ID draft-ietf-xrblock-rtcp-xr-summary-stat-11, 518 March 2013. 520 Appendix A. Metrics represented using RFC6390 Template 522 RFC EDITOR NOTE: please change XXXX in [RFCXXXX] by the new RFC 523 number, when assigned. 525 a. Threshold Metric 527 * Metric Name: Threshold in RTP 529 * Metric Description: The Threshold is equivalent to Gmin in 530 [RFC3611], i.e. the number of successive RTP packets that must 531 be received prior to and following a lost RTP packet in order 532 for this lost RTP packet to be regarded as part of a gap. 534 * Method of Measurement or Calculation: See section 3.2, 535 Threshold definition [RFCXXXX]. 537 * Units of Measurement: See section 3.2, Threshold definition 538 [RFCXXXX]. 540 * Measurement Point(s) with Potential Measurement Domain: See 541 section 3, 1st paragraph [RFCXXXX]. 543 * Measurement Timing: See section 3, 1st paragraph [RFCXXXX] for 544 measurement timing and section 3.2 [RFCXXXX] for Interval 545 Metric flag. 547 * Use and applications: See section 1.4 [RFCXXXX]. 549 * Reporting model: See RFC3611. 551 b. Sum of Burst Durations Metric 553 * Metric Name: Sum of Burst Durations in RTP 555 * Metric Description: The total duration of bursts of lost RTP 556 packets in the period of the report. 558 * Method of Measurement or Calculation: See section 3.2, Sum of 559 Burst Durations definition [RFCXXXX]. 561 * Units of Measurement: See section 3.2, Sum of Burst Durations 562 definition [RFCXXXX]. 564 * Measurement Point(s) with Potential Measurement Domain: See 565 section 3, 1st paragraph [RFCXXXX]. 567 * Measurement Timing: See section 3, 1st paragraph [RFCXXXX] for 568 measurement timing and section 3.2 [RFCXXXX] for Interval 569 Metric flag. 571 * Use and applications: See section 1.4 [RFCXXXX]. 573 * Reporting model: See RFC3611. 575 c. Packets lost in bursts Metric 577 * Metric Name: RTP Packets lost in bursts 579 * Metric Description: The total number of RTP packets lost 580 during loss bursts. 582 * Method of Measurement or Calculation: See section 3.2, Packets 583 lost in bursts definition [RFCXXXX]. 585 * Units of Measurement: See section 3.2, Packets lost in bursts 586 definition [RFCXXXX]. 588 * Measurement Point(s) with Potential Measurement Domain: See 589 section 3, 1st paragraph [RFCXXXX]. 591 * Measurement Timing: See section 3, 1st paragraph [RFCXXXX] for 592 measurement timing and section 3.2 [RFCXXXX] for Interval 593 Metric flag. 595 * Use and applications: See section 1.4 [RFCXXXX]. 597 * Reporting model: See RFC3611. 599 d. Total packets expected in bursts Metric 601 * Metric Name: Total RTP packets expected in bursts 603 * Metric Description: The total number of RTP packets expected 604 during loss bursts (that is, the sum of received RTP packets 605 and lost RTP packets). 607 * Method of Measurement or Calculation: See section 3.2, Total 608 packets expected in bursts definition [RFCXXXX]. 610 * Units of Measurement: See section 3.2, Total packets expected 611 in bursts definition [RFCXXXX]. 613 * Measurement Point(s) with Potential Measurement Domain: See 614 section 3, 1st paragraph [RFCXXXX]. 616 * Measurement Timing: See section 3, 1st paragraph [RFCXXXX] for 617 measurement timing and section 3.2 [RFCXXXX] for Interval 618 Metric flag. 620 * Use and applications: See section 1.4 [RFCXXXX]. 622 * Reporting model: See RFC3611. 624 e. Number of bursts Metric 626 * Metric Name: Number of bursts in RTP 628 * Metric Description: The total duration of bursts of lost RTP 629 packets in the period of the report. 631 * Method of Measurement or Calculation: See section 3.2, Number 632 of bursts definition [RFCXXXX]. 634 * Units of Measurement: See section 3.2, Number of bursts 635 definition [RFCXXXX]. 637 * Measurement Point(s) with Potential Measurement Domain: See 638 section 3, 1st paragraph [RFCXXXX]. 640 * Measurement Timing: See section 3, 1st paragraph [RFCXXXX] for 641 measurement timing and section 3.2 [RFCXXXX] for Interval 642 Metric flag. 644 * Use and applications: See section 1.4 [RFCXXXX]. 646 * Reporting model: See RFC3611. 648 f. Sum of Squares of Burst Durations Metric 650 * Metric Name: Sum of Squares of Burst Durations in RTP 652 * Metric Description: The sum of the squares of burst durations 653 (where individual burst durations are expressed in ms) over in 654 the period of the report. 656 * Method of Measurement or Calculation: See section 3.2, Sum of 657 Squares of Burst Durations definition [RFCXXXX]. 659 * Units of Measurement: See section 3.2, Sum of Squares of Burst 660 Durations definition [RFCXXXX]. 662 * Measurement Point(s) with Potential Measurement Domain: See 663 section 3, 1st paragraph [RFCXXXX]. 665 * Measurement Timing: See section 3, 1st paragraph [RFCXXXX] for 666 measurement timing and section 3.2 [RFCXXXX] for Interval 667 Metric flag. 669 * Use and applications: See section 1.4 [RFCXXXX]. 671 * Reporting model: See RFC3611. 673 Appendix B. Change Log 675 Note to the RFC-Editor: please remove this section prior to 676 publication as an RFC. 678 B.1. draft-ietf-xrblock-rtcp-xr-burst-gap-loss-10 680 The following are the major changes compared to previous version: 682 o IESG Review comments are addressed in this version. 684 B.2. draft-ietf-xrblock-rtcp-xr-burst-gap-loss-09 686 The following are the major changes compared to previous version: 688 o IETF LC comments are addressed together with AD's comment on 689 Normative language in this version. 691 B.3. draft-ietf-xrblock-rtcp-xr-burst-gap-loss-08 693 The following are the major changes compared to previous version: 695 o Move RFC6709 as one informative reference. 697 B.4. draft-ietf-xrblock-rtcp-xr-burst-gap-loss-07 699 The following are the major changes compared to previous version: 701 o Editorial changes based on comments in the WGLC. 703 B.5. draft-ietf-xrblock-rtcp-xr-burst-gap-loss-06 705 The following are the major changes compared to previous version: 707 o SDP update based on SDP Directorate Review. 709 o Add some texts to get consistent with RFC6798 and Delay draft. 711 B.6. draft-ietf-xrblock-rtcp-xr-burst-gap-loss-04 713 The following are the major changes compared to previous version: 715 o Outdated reference update. 717 o Editorial changes based on comments that applied to PDV and Delay 718 drafts. 720 Authors' Addresses 722 Alan Clark 723 Telchemy Incorporated 724 2905 Premiere Parkway, Suite 280 725 Duluth, GA 30097 726 USA 728 Email: alan.d.clark@telchemy.com 730 Sunshine Zhang 731 Shanghai Research Institute of China Telecom Corporation Limited 732 No.1835,South Pudong Road 733 Shanghai 200122 734 China 736 Email: zhangyx@sttri.com.cn 738 Jing Zhao 739 Shanghai Research Institute of China Telecom Corporation Limited 740 No.1835,South Pudong Road 741 Shanghai 200122 742 China 744 Email: zhaojing@sttri.com.cn 746 Qin Wu (editor) 747 Huawei 748 101 Software Avenue, Yuhua District 749 Nanjing, Jiangsu 210012 750 China 752 Email: sunseawq@huawei.com