idnits 2.17.00 (12 Aug 2021) /tmp/idnits22834/draft-wu-xrblock-rtcp-xr-one-way-delay-02.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 (July 13, 2012) is 3592 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reference: RFC 2679 (Obsoleted by RFC 7679) ** Obsolete normative reference: RFC 4566 (Obsoleted by RFC 8866) == Outdated reference: draft-ietf-xrblock-rtcp-xr-delay has been published as RFC 6843 == Outdated reference: draft-ietf-avtcore-idms has been published as RFC 7272 == Outdated reference: draft-ietf-avtcore-monarch has been published as RFC 6792 Summary: 2 errors (**), 0 flaws (~~), 4 warnings (==), 1 comment (--).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 R. Brandenburg 3 Internet-Draft TNO 4 Intended status: Standards Track K. Gross 5 Expires: January 14, 2013 AVA Networks 6 Q. Wu 7 Huawei 8 F. Boronat 9 M. Montagud 10 UPVLC 11 July 13, 2012 13 RTCP XR Report Block for One Way Delay metric Reporting 14 draft-wu-xrblock-rtcp-xr-one-way-delay-02.txt 16 Abstract 18 This document defines an RTCP XR Report Block that allows the 19 reporting of One Way Delay metrics for use in a range of RTP 20 applications. 22 Status of this Memo 24 This Internet-Draft is submitted in full conformance with the 25 provisions of BCP 78 and BCP 79. 27 Internet-Drafts are working documents of the Internet Engineering 28 Task Force (IETF). Note that other groups may also distribute 29 working documents as Internet-Drafts. The list of current Internet- 30 Drafts is at http://datatracker.ietf.org/drafts/current/. 32 Internet-Drafts are draft documents valid for a maximum of six months 33 and may be updated, replaced, or obsoleted by other documents at any 34 time. It is inappropriate to use Internet-Drafts as reference 35 material or to cite them other than as "work in progress." 37 This Internet-Draft will expire on January 14, 2013. 39 Copyright Notice 41 Copyright (c) 2012 IETF Trust and the persons identified as the 42 document authors. All rights reserved. 44 This document is subject to BCP 78 and the IETF Trust's Legal 45 Provisions Relating to IETF Documents 46 (http://trustee.ietf.org/license-info) in effect on the date of 47 publication of this document. Please review these documents 48 carefully, as they describe your rights and restrictions with respect 49 to this document. Code Components extracted from this document must 50 include Simplified BSD License text as described in Section 4.e of 51 the Trust Legal Provisions and are provided without warranty as 52 described in the Simplified BSD License. 54 Table of Contents 56 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 57 1.1. Packet One Way Delay Metrics Block . . . . . . . . . . . . 3 58 1.2. RTCP and RTCP XR Reports . . . . . . . . . . . . . . . . . 3 59 1.3. Performance Metrics Framework . . . . . . . . . . . . . . 3 60 1.4. Applicability . . . . . . . . . . . . . . . . . . . . . . 3 61 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4 62 2.1. Standards Language . . . . . . . . . . . . . . . . . . . . 4 63 3. One Way Delay Block . . . . . . . . . . . . . . . . . . . . . 5 64 3.1. Report Block Structure . . . . . . . . . . . . . . . . . . 5 65 3.2. Definition of Fields in One Way Delay Metrics Report 66 Block . . . . . . . . . . . . . . . . . . . . . . . . . . 5 67 4. Clock synchronization for one way delay metrics . . . . . . . 7 68 5. One way delay calculation based on measurement method in 69 RFC2679 . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 70 6. SDP Signaling . . . . . . . . . . . . . . . . . . . . . . . . 9 71 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10 72 7.1. New RTCP XR Block Type value . . . . . . . . . . . . . . . 10 73 7.2. New RTCP XR SDP Parameter . . . . . . . . . . . . . . . . 10 74 7.3. Contact information for registrations . . . . . . . . . . 10 75 8. Security Considerations . . . . . . . . . . . . . . . . . . . 11 76 9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 12 77 9.1. Normative References . . . . . . . . . . . . . . . . . . . 12 78 9.2. Informative References . . . . . . . . . . . . . . . . . . 12 79 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 13 81 1. Introduction 83 1.1. Packet One Way Delay Metrics Block 85 [I-D.ietf-xrblock-rtcp-xr-delay] defines the new block type 86 supporting the reporting of the mean, minimum and maximum values of 87 the network round-trip delay between media source(source) and media 88 receiver(destination). However none of these metrics allow a 89 receiver to report one way delay from source to destination or the 90 other way around. As described in [RFC2679], the path from a source 91 to a destination may be different than the path from the destination 92 back to the source. Even when the two paths are symmetric, they may 93 have radically different performance characteristics. Therefore the 94 measurement of one-way delay can not be roughly estimated by the 95 round-trip delay for many applications in the asymmetric network and 96 even symmetric network. 98 This draft defines a new block type to augment those defined in 99 [RFC3611] for use in a range of RTP applications. The new block type 100 supports the reporting of the mean, minimum, maximum values of one 101 way network delay between RTP interfaces in peer RTP end systems, as 102 measured, for example, using the method described in [RFC2679]. 104 This metrics belong to the class of transport metrics defined in 105 [MONARCH]. 107 1.2. RTCP and RTCP XR Reports 109 The use of RTCP for reporting is defined in [RFC3550]. [RFC3611] 110 defined an extensible structure for reporting using an RTCP Extended 111 Report (XR). This draft defines a new Extended Report block. The 112 use of Extended Report blocks is defined by [RFC3611]. 114 1.3. Performance Metrics Framework 116 The Performance Metrics Framework [RFC6390] provides guidance on the 117 definition and specification of performance metrics. The RTP 118 Monitoring Architectures [MONARCH] provides guideline for reporting 119 block format using RTCP XR. The Metrics Block described in this 120 document are in accordance with the guidelines in [RFC6390] and 121 [MONARCH]. 123 1.4. Applicability 125 These metrics are applicable to a range of delay-sensitive RTP 126 applications in which this report block would be useful, such as some 127 IDMS use cases (e.g., video wall, network games, networked 128 loudspeakers, etc., see Draft IDMS [IDMS]). 130 2. Terminology 132 2.1. Standards Language 134 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 135 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 136 document are to be interpreted as described in RFC 2119 [RFC2119]. 138 3. One Way Delay Block 140 Metrics in this block report on one way packet delay in the stream 141 arriving at the RTP system. 143 3.1. Report Block Structure 145 One Way Delay metrics block 147 0 1 2 3 148 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 7 149 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 150 | BT=OWD | I | resv. | block length = 4 | 151 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 152 | SSRC of Source | 153 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 154 | Median-One-way-Network-Delay | 155 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 156 | Max-One-way-Network-Delay | 157 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 158 | Min-One-way-Network-Delay | 159 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 161 Figure 1: Report Block Structure 163 3.2. Definition of Fields in One Way Delay Metrics Report Block 165 Block type (BT): 8 bits 167 A One way Delay Report Block is identified by the constant OWD. 169 [Note to RFC Editor: please replace OWD with the IANA provided 170 RTCP XR block type for this block.] 172 Interval Metric flag (I): 2 bits 174 This field is used to indicate whether the One Way Metrics are 175 Sampled, Interval or Cumulative metrics [MONARCH], that is, 176 whether the reported values applies to the most recent measurement 177 interval duration between successive metrics reports (I=10) (the 178 Interval Duration), to the accumulation period characteristic of 179 cumulative measurements (I=11) (the Cumulative Duration) or is a 180 sampled instantaneous value (I=01). 182 Reserved (resv): 6 bits 184 These bits are reserved. They SHOULD be set to zero by senders 185 and MUST be ignored by receivers. 187 block length: 16 bits 189 The length of this report block in 32-bit words, minus one. For 190 the Delay block, the block length is equal to 4. 192 SSRC of source: 32 bits 194 The SSRC of the media source shall be set to the value of the SSRC 195 identifier carried in the RTP header [RFC3550] of the RTP packet 196 to which the XR relates. 198 Median-One-way-Network-Delay: 32 bits 200 The Mean One way Delay is the mean value of the RTP-to- RTP 201 interface one way delay in units of 1/65536 seconds over the 202 measurement period. It can be calculated using RTCP SR/RR or RTP 203 media packet according to section 3.6 of [RFC2679]. For details 204 on one way delay calculation, see Section 5. 206 Max-One-way-Network-Delay: 32 bits 208 The Max One Way Delay is the maximum value of the RTP- to-RTP 209 interface one way delay in units of 1/65536 seconds over the 210 measurement period. It can be calculated using RTCP SR/RR or RTP 211 media packet according to section 3.6 of [RFC2679]. For details 212 on one way delay calculation, see Section 5. 214 Min-One-way-Network-Delay: 32 bits 216 The Max One Way Delay is the minimum value of the RTP- to-RTP 217 interface one way delay in units of 1/65536 seconds over the 218 measurement period. It can be calculated using RTCP SR/RR or RTP 219 media packet according to section 3.6 of [RFC2679]. For details 220 on one way delay calculation, see Section 5. 222 4. Clock synchronization for one way delay metrics 224 This subsection provides informative guidance on use of methodology 225 for one way delay metrics measurement. 227 As specified in the methodology of [RFC2679], it is important for 228 media source (Src) and media receiver (Dst) to synchronize very 229 closely since one way delay values will often be as low as the 100 230 usec to 10 msec range. In order to arrange Src and Des synchronized 231 before measurement method is applied, a participant at the Dst can 232 indicate which synchronization source is being used at the moment. A 233 participant can also indicate any other synchronization sources 234 available to it. This allows multiple participants in an RTP session 235 to use the same or a similar clock synchronization source for their 236 session. 238 5. One way delay calculation based on measurement method in RFC2679 240 TBC. 242 6. SDP Signaling 244 [RFC3611] defines the use of SDP (Session Description Protocol) 245 [RFC4566] for signaling the use of XR blocks. XR blocks MAY be used 246 without prior signaling. 248 This section augments the SDP [RFC4566] attribute "rtcp-xr" defined 249 in [RFC3611] by providing an additional value of "xr-format" to 250 signal the use of the report block defined in this document. 252 rtcp-xr-attrib = "a=" "rtcp-xr" ":" [xr-format *(SP xr-format)] CRLF 254 (defined in [RFC3611]) 256 xr-format =/ xr-one-way-delay-block 258 xr-one-way-delay-block ="one way delay" 260 7. IANA Considerations 262 New block types for RTCP XR are subject to IANA registration. For 263 general guidelines on IANA considerations for RTCP XR, refer to 264 [RFC3611]. 266 7.1. New RTCP XR Block Type value 268 This document assigns the block type value OWD in the IANA "RTCP XR 269 Block Type Registry" to the "One Way Delay Metrics Block". 271 [Note to RFC Editor: please replace OWD with the IANA provided RTCP 272 XR block type for this block.] 274 7.2. New RTCP XR SDP Parameter 276 This document also registers a new parameter "one way delay" in the 277 "RTCP XR SDP Parameters Registry". 279 7.3. Contact information for registrations 281 The contact information for the registrations is: 283 Qin Wu (sunseawq@huawei.com) 285 101 Software Avenue, Yuhua District 286 Nanjing, Jiangsu 210012 287 China 289 8. Security Considerations 291 It is believed that this proposed RTCP XR report block introduces no 292 new security considerations beyond those described in [RFC3611]. 293 This block does not provide per-packet statistics so the risk to 294 confidentiality documented in Section 7, paragraph 3 of [RFC3611] 295 does not apply. 297 9. References 299 9.1. Normative References 301 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 302 Requirement Levels", March 1997. 304 [RFC2679] Almes, G., Kalidindi, S., and M. Zekauskas, "A One-way 305 Delay Metric for IPPM", RFC 2679, September 1999. 307 [RFC3550] Schulzrinne, H., "RTP: A Transport Protocol for Real-Time 308 Applications", RFC 3550, July 2003. 310 [RFC3611] Friedman, T., Caceres, R., and A. Clark, "RTP Control 311 Protocol Extended Reports (RTCP XR)", November 2003. 313 [RFC4566] Handley, M., Jacobson, V., and C. Perkins, "SDP: Session 314 Description Protocol", July 2006. 316 9.2. Informative References 318 [I-D.ietf-xrblock-rtcp-xr-delay] 319 Hunt, G., Clark, A., Gross, K., and Q. Wu, "RTCP XR Report 320 Block for Delay metric Reporting", 321 ID draft-ietf-xrblock-rtcp-xr-delay-06, May 2012. 323 [IDMS] Brandenburg, R., Stokking, H., and M. Deventer, "RTCP for 324 inter-destination media synchronization", 325 ID draft-ietf-avtcore-idms-05, June 2012. 327 [MONARCH] Hunt, G., "Monitoring Architectures for RTP", 328 ID draft-ietf-avtcore-monarch-17, June 2012. 330 [RFC6390] Clark, A. and B. Claise, "Framework for Performance Metric 331 Development", RFC 6390, October 2011. 333 Authors' Addresses 335 R.van Brandenburg 336 TNO 338 Email: ray.vanbrandenburg@tno.nl 340 Kevin Gross 341 AVA Networks 343 Email: kevin.gross@avanw.com 345 Qin Wu 346 Huawei 347 101 Software Avenue, Yuhua District 348 Nanjing, Jiangsu 210012 349 China 351 Email: sunseawq@huawei.com 353 Fernando Boronat Segu 354 Universitat Politecnica de Valencia 355 IGIC Institute, Campus de Gandia, C/ Paraninfo, 1, Grao de Gandia 356 Valencia 46730 357 Spain 359 Email: fboronat@dcom.upv.es 361 M. Montagud 362 Universitat Politecnica de Valencia 363 IGIC Institute, Campus de Gandia, C/ Paraninfo, 1, Grao de Gandia 364 Valencia 46730 365 Spain 367 Email: mamontor@posgrado.upv.es