idnits 2.17.1 draft-ietf-xrblock-rtcp-xr-delay-09.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 (September 18, 2012) is 4239 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references to lower-maturity documents in RFCs) ** Obsolete normative reference: RFC 4566 (Obsoleted by RFC 8866) == Outdated reference: A later version (-10) exists of draft-ietf-xrblock-rtcp-xr-meas-identity-09 == Outdated reference: A later version (-22) exists of draft-ietf-avtcore-monarch-18 Summary: 1 error (**), 0 flaws (~~), 3 warnings (==), 1 comment (--).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 K. Gross 5 Expires: March 22, 2013 AVA Networks 6 Q. Wu 7 Huawei 8 September 18, 2012 10 RTP Control Protocol (RTCP) Extended Report (XR) Block for Delay metric 11 Reporting 12 draft-ietf-xrblock-rtcp-xr-delay-09.txt 14 Abstract 16 This document defines an RTP Control Protocol(RTCP) Extended Report 17 (XR) Block that allows the reporting of Delay metrics for use in a 18 range of Real-time Transport Protocol (RTP) applications. 20 Status of this Memo 22 This Internet-Draft is submitted in full conformance with the 23 provisions of BCP 78 and BCP 79. 25 Internet-Drafts are working documents of the Internet Engineering 26 Task Force (IETF). Note that other groups may also distribute 27 working documents as Internet-Drafts. The list of current Internet- 28 Drafts is at http://datatracker.ietf.org/drafts/current/. 30 Internet-Drafts are draft documents valid for a maximum of six months 31 and may be updated, replaced, or obsoleted by other documents at any 32 time. It is inappropriate to use Internet-Drafts as reference 33 material or to cite them other than as "work in progress." 35 This Internet-Draft will expire on March 22, 2013. 37 Copyright Notice 39 Copyright (c) 2012 IETF Trust and the persons identified as the 40 document authors. All rights reserved. 42 This document is subject to BCP 78 and the IETF Trust's Legal 43 Provisions Relating to IETF Documents 44 (http://trustee.ietf.org/license-info) in effect on the date of 45 publication of this document. Please review these documents 46 carefully, as they describe your rights and restrictions with respect 47 to this document. Code Components extracted from this document must 48 include Simplified BSD License text as described in Section 4.e of 49 the Trust Legal Provisions and are provided without warranty as 50 described in the Simplified BSD License. 52 Table of Contents 54 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 55 1.1. Packet Delay Metrics Block . . . . . . . . . . . . . . . . 3 56 1.2. RTCP and RTCP XR Reports . . . . . . . . . . . . . . . . . 3 57 1.3. Performance Metrics Framework . . . . . . . . . . . . . . 3 58 1.4. Applicability . . . . . . . . . . . . . . . . . . . . . . 3 59 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4 60 2.1. Standards Language . . . . . . . . . . . . . . . . . . . . 4 61 3. Delay Block . . . . . . . . . . . . . . . . . . . . . . . . . 5 62 3.1. Report Block Structure . . . . . . . . . . . . . . . . . . 5 63 3.2. Definition of Fields in Delay Metrics Report Block . . . . 5 64 4. SDP Signaling . . . . . . . . . . . . . . . . . . . . . . . . 8 65 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 9 66 5.1. New RTCP XR Block Type value . . . . . . . . . . . . . . . 9 67 5.2. New RTCP XR SDP Parameter . . . . . . . . . . . . . . . . 9 68 5.3. Contact information for registrations . . . . . . . . . . 9 69 6. Security Considerations . . . . . . . . . . . . . . . . . . . 10 70 7. Contributors . . . . . . . . . . . . . . . . . . . . . . . . . 11 71 8. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 12 72 9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 13 73 9.1. Normative References . . . . . . . . . . . . . . . . . . . 13 74 9.2. Informative References . . . . . . . . . . . . . . . . . . 13 75 Appendix A. Change Log . . . . . . . . . . . . . . . . . . . . . 14 76 A.1. draft-ietf-xrblock-rtcp-xr-delay-09 . . . . . . . . . . . 14 77 A.2. draft-ietf-xrblock-rtcp-xr-delay-08 . . . . . . . . . . . 14 78 A.3. draft-ietf-xrblock-rtcp-xr-delay-07 . . . . . . . . . . . 14 79 A.4. draft-ietf-xrblock-rtcp-xr-delay-06 . . . . . . . . . . . 14 80 A.5. draft-ietf-xrblock-rtcp-xr-delay-05 . . . . . . . . . . . 14 81 A.6. draft-ietf-xrblock-rtcp-xr-delay-04 . . . . . . . . . . . 14 82 A.7. draft-ietf-xrblock-rtcp-xr-delay-03 . . . . . . . . . . . 15 83 A.8. draft-ietf-xrblock-rtcp-xr-delay-02 . . . . . . . . . . . 15 84 A.9. draft-ietf-xrblock-rtcp-xr-delay-01 . . . . . . . . . . . 15 85 A.10. draft-ietf-xrblock-rtcp-xr-delay-00 . . . . . . . . . . . 15 86 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 16 88 1. Introduction 90 1.1. Packet Delay Metrics Block 92 This draft defines a new block type to augment those defined in 93 [RFC3611] for use in a range of RTP applications. The new block type 94 supports the reporting of the mean, minimum and maximum values of the 95 network round-trip delay between RTP interfaces in peer RTP end 96 systems as measured, for example, using the RTCP method described in 97 [RFC3550]. It also supports reporting of the component of the round- 98 trip delay internal to the local RTP system. 100 The network metrics belong to the class of packet transport delay 101 metrics defined in [MONARCH]. 103 1.2. RTCP and RTCP XR Reports 105 The use of RTCP for reporting is defined in [RFC3550]. [RFC3611] 106 defined an extensible structure for reporting using an RTCP Extended 107 Report (XR). This draft defines a new Extended Report block that 108 MUST be used as defined in [RFC3550] and [RFC3611]. 110 1.3. Performance Metrics Framework 112 The Performance Metrics Framework [RFC6390] provides guidance on the 113 definition and specification of performance metrics. The RTP 114 Monitoring Architectures [MONARCH] provides guideline for reporting 115 block format using RTCP XR. The Metrics Block described in this 116 document are in accordance with the guidelines in [RFC6390] and 117 [MONARCH]. 119 1.4. Applicability 121 These metrics are applicable to a range of RTP applications in which 122 this report block would be useful, such as multimedia conferencing 123 and streaming audio and video. Knowledge of the round-trip delay and 124 delay characteristics can aid other receivers in sizing their receive 125 buffers and selecting a playout delay. The same information is also 126 valuable to network managers in troubleshooting network and user 127 experience issues. 129 2. Terminology 131 2.1. Standards Language 133 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 134 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 135 document are to be interpreted as described in RFC 2119 [RFC2119]. 137 3. Delay Block 139 Metrics in this block report on packet delay in the stream arriving 140 at the RTP system. The measurement of these metrics are made either 141 at the receiving end of the RTP stream or at the sending end of the 142 RTP stream. Instances of this Metrics Block refer by Synchronization 143 source (SSRC) to the separate auxiliary Measurement Information block 144 [MEASI] which contains measurement intervals. This metric block 145 relies on the measurement interval in the Measurement Information 146 block indicating the span of the report and SHOULD be sent in the 147 same compound RTCP packet as the measurement information block. If 148 the measurement interval is not received in the same compound RTCP 149 packet as this metric block, this metric block SHOULD be discarded 150 (See [MONARCH] section 5.4 for more timing details). 152 3.1. Report Block Structure 154 Delay metrics block 156 0 1 2 3 157 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 7 158 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 159 | BT=NDEL | I | resv. | block length = 6 | 160 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 161 | SSRC of Source | 162 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 163 | Mean Network Round Trip Delay | 164 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 165 | Min Network Round Trip Delay | 166 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 167 | Max Network Round Trip Delay | 168 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 169 | End System Delay - Seconds (bit 0-31) | 170 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 171 | End System Delay - Fraction (bit 0-31) | 172 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 174 Figure 1: Report Block Structure 176 3.2. Definition of Fields in Delay Metrics Report Block 178 Block type (BT): 8 bits 180 A Delay Report Block is identified by the constant NDEL. 182 [Note to RFC Editor: please replace NDEL with the IANA provided 183 RTCP XR block type for this block.] 185 Interval Metric flag (I): 2 bit 187 This field is used to indicate whether the Delay metrics are 188 Sampled, Interval or Cumulative metrics, that is, whether the 189 reported values applies to the most recent measurement interval 190 duration between successive metrics reports (I=10) (the Interval 191 Duration) or to the accumulation period characteristic of 192 cumulative measurements (I=11) (the Cumulative Duration) or is a 193 sampled instantaneous value (I=01) (Sampled Value). 195 Reserved (resv): 6 bits 197 These bits are reserved. They MUST be set to zero by senders and 198 SHOULD be ignored by receivers. 200 block length: 16 bits 202 The length of this report block in 32-bit words, minus one. For 203 the Delay block, the block length is equal to 6. 205 SSRC of source: 32 bits 207 As defined in Section 4.1 of [RFC3611]. 209 Mean Network Round Trip Delay: 32 bits 211 The Mean Network Round Trip Delay is the mean value of the RTP-to- 212 RTP interface round trip delay over the measurement period, 213 expressed in units of 1/65536 seconds. This value is typically 214 determined using RTCP SR/RR (See RFC 3550 section 6.4.1). It also 215 can be determined using RTCP Receiver Reference Time Report Block 216 and DLRR Report Block (See RFC3611 section 4.5). 218 If only one measurement of Round Trip Delay is available for the 219 timespan of the report (i.e.,the measurement period) (whether 220 Interval or Cumulative), this single value SHOULD be reported as 221 the mean value. 223 If the measurement is unavailable, the value of this field with 224 all bits set to 1 MUST be reported. 226 Min Network Round Trip Delay: 32 bits 228 The Min Network Round Trip Delay is the minimum value of the RTP- 229 to-RTP interface round trip delay over the measurement period, 230 expressed in units of 1/65536 seconds. This value is typically 231 determined using RTCP SR/RR. It also can be determined using RTCP 232 Receiver Reference Time Report Block and DLRR Report Block. 234 If only one measurement of Round Trip Delay is available for the 235 timespan of the report (i.e.,the measurement period) (whether 236 Interval or Cumulative), this single value SHOULD be reported as 237 the minimum value. 239 If the measurement is unavailable, the value of this field with 240 all bits set to 1 MUST be reported. 242 Max Network Round Trip Delay: 32 bits 244 The Max Network Round Trip Delay is the maximum value of the RTP- 245 to-RTP interface round trip delay over the measurement period, 246 expressed in units of 1/65536 seconds. This value is typically 247 determined using RTCP SR/RR. It also can be determined using RTCP 248 Receiver Reference Time Report Block and DLRR Report Block. 250 If only one measurement of Round Trip Delay is available for the 251 timespan of the report (i.e.,the measurement period) (whether 252 Interval or Cumulative), this single value SHOULD be reported as 253 the maximum value. 255 If the measurement is unavailable, the value of this field with 256 all bits set to 1 MUST be reported. 258 End System Delay: 64 bits 260 The End System Delay is the internal round trip delay within the 261 reporting endpoint, calculated using the nominal value of the 262 jitter buffer delay plus the accumulation/encoding and decoding/ 263 playout delay associated with the codec being used. The value of 264 this field is represented using a 64-bit NTP-format timestamp as 265 defined in [RFC5905], which is 64-bit unsigned fixed-point number 266 with the integer part in the first 32 bits and the fractional part 267 in the last 32 bits. 269 If the measurement is unavailable, the value of this field with 270 all bits set to 1 MUST be reported. 272 4. SDP Signaling 274 [RFC3611] defines the use of SDP (Session Description Protocol) 275 [RFC4566] for signaling the use of XR blocks. XR blocks MAY be used 276 without prior signaling. 278 This section augments the SDP [RFC4566] attribute "rtcp-xr" defined 279 in [RFC3611] by providing an additional value of "xr-format" to 280 signal the use of the report block defined in this document. 282 xr-format =/ xr-delay-block 284 xr-delay-block ="delay" 286 5. IANA Considerations 288 New block types for RTCP XR are subject to IANA registration. For 289 general guidelines on IANA considerations for RTCP XR, refer to 290 [RFC3611]. 292 5.1. New RTCP XR Block Type value 294 This document assigns the block type value NDEL in the IANA "RTCP XR 295 Block Type Registry" to the "Delay Metrics Block". 297 [Note to RFC Editor: please replace NDEL with the IANA provided RTCP 298 XR block type for this block.] 300 5.2. New RTCP XR SDP Parameter 302 This document also registers a new parameter "delay" in the "RTCP XR 303 SDP Parameters Registry". 305 5.3. Contact information for registrations 307 The contact information for the registrations is: 309 Qin Wu (sunseawq@huawei.com) 311 101 Software Avenue, Yuhua District 312 Nanjing, Jiangsu 210012 313 China 315 6. Security Considerations 317 It is believed that this proposed RTCP XR report block introduces no 318 new security considerations beyond those described in [RFC3611]. 319 This block does not provide per-packet statistics so the risk to 320 confidentiality documented in Section 7, paragraph 3 of [RFC3611] 321 does not apply. 323 7. Contributors 325 Geoff Hunt wrote the initial version of this document. 327 8. Acknowledgments 329 The authors gratefully acknowledge the comments and contributions 330 made by Bruce Adams, Philip Arden, Amit Arora, Bob Biskner, Kevin 331 Connor, Claus Dahm, Randy Ethier, Roni Even, Jim Frauenthal, Albert 332 Higashi, Tom Hock, Shane Holthaus, Paul Jones, Rajesh Kumar, Keith 333 Lantz, Mohamed Mostafa, Amy Pendleton, Colin Perkins, Mike Ramalho, 334 Ravi Raviraj, Albrecht Schwarz, Tom Taylor, and Hideaki Yamada,Jing 335 Zhao,Kevin Gross, Colin Perkins, Charles Eckel, Glen Zorn,Shida 336 Schubert. 338 9. References 340 9.1. Normative References 342 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 343 Requirement Levels", March 1997. 345 [RFC3550] Schulzrinne, H., "RTP: A Transport Protocol for Real-Time 346 Applications", RFC 3550, July 2003. 348 [RFC3611] Friedman, T., Caceres, R., and A. Clark, "RTP Control 349 Protocol Extended Reports (RTCP XR)", November 2003. 351 [RFC4566] Handley, M., Jacobson, V., and C. Perkins, "SDP: Session 352 Description Protocol", July 2006. 354 [RFC5905] Mills, D., Martin, J., Burbank, J., and W. Kasch, "Network 355 Time Protocol Version 4: Protocol and Algorithms 356 Specification", RFC 5905, June 2010. 358 9.2. Informative References 360 [MEASI] Hunt, G., "Measurement Identity and information Reporting 361 using SDES item and XR Block", 362 ID draft-ietf-xrblock-rtcp-xr-meas-identity-09, July 2012. 364 [MONARCH] Hunt, G., "Monitoring Architectures for RTP", 365 ID draft-ietf-avtcore-monarch-18, August 2012. 367 [RFC6390] Clark, A. and B. Claise, "Framework for Performance Metric 368 Development", RFC 6390, October 2011. 370 Appendix A. Change Log 372 Note to the RFC-Editor: please remove this section prior to 373 publication as an RFC. 375 A.1. draft-ietf-xrblock-rtcp-xr-delay-09 377 The following are the major changes to previous version : 379 o Editorial changes based on comments that are applied to PDV draft. 381 A.2. draft-ietf-xrblock-rtcp-xr-delay-08 383 The following are the major changes to previous version : 385 o Move Geoff Hunt from author list to Contributors section based on 386 his suggestion. 388 A.3. draft-ietf-xrblock-rtcp-xr-delay-07 390 The following are the major changes to previous version : 392 o Editorial changes. 394 o Reference updates. 396 A.4. draft-ietf-xrblock-rtcp-xr-delay-06 398 The following are the major changes to previous version : 400 o Editorial changes. 402 A.5. draft-ietf-xrblock-rtcp-xr-delay-05 404 The following are the major changes to previous version : 406 o One typo fixed. 408 A.6. draft-ietf-xrblock-rtcp-xr-delay-04 410 The following are the major changes to previous version : 412 o Revise the definition of sampled metric to get alignment with 413 MONARCH. 415 o Clarify sending the metric block in the same RTCP compound packet 416 as the measurement information block. 418 A.7. draft-ietf-xrblock-rtcp-xr-delay-03 420 The following are the major changes to previous version : 422 o Allocate 64 bit for end system delay and represent it using 64 bit 423 NTP-Timestamp. 425 o Other editorial changes. 427 A.8. draft-ietf-xrblock-rtcp-xr-delay-02 429 The following are the major changes to previous version : 431 o Allocate 32bits for each metrics and change unit for each metric 432 from ms to 1/65536 seconds. 434 A.9. draft-ietf-xrblock-rtcp-xr-delay-01 436 The following are the major changes to previous version : 438 o Updated references. 440 o Allocate one more bit for Interval metric flag to indicate sampled 441 metric can be used. 443 o add a few clarification text for failure mode. 445 A.10. draft-ietf-xrblock-rtcp-xr-delay-00 447 The following are the major changes to previous version : 449 o Changed BNF for SDP following Christian Groves' and Tom Taylor's 450 comments (4th and 5th May 2009). 452 o Updated references. 454 Authors' Addresses 456 Alan Clark 457 Telchemy Incorporated 458 2905 Premiere Parkway, Suite 280 459 Duluth, GA 30097 460 USA 462 Email: alan.d.clark@telchemy.com 464 Kevin Gross 465 AVA Networks 467 Email: kevin.gross@avanw.com 469 Qin Wu 470 Huawei 471 101 Software Avenue, Yuhua District 472 Nanjing, Jiangsu 210012 473 China 475 Email: sunseawq@huawei.com