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Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Working Group M. Bagnulo 3 Internet-Draft UC3M 4 Intended status: Best Current Practice B. Claise 5 Expires: May 3, 2017 Cisco Systems, Inc. 6 P. Eardley 7 BT 8 A. Morton 9 AT&T Labs 10 A. Akhter 11 Consultant 12 October 30, 2016 14 Registry for Performance Metrics 15 draft-ietf-ippm-metric-registry-09 17 Abstract 19 This document defines the format for the Performance Metrics registry 20 and defines the IANA Registry for Performance Metrics. This document 21 also gives a set of guidelines for Registered Performance Metric 22 requesters and reviewers. 24 Status of This Memo 26 This Internet-Draft is submitted in full conformance with the 27 provisions of BCP 78 and BCP 79. 29 Internet-Drafts are working documents of the Internet Engineering 30 Task Force (IETF). Note that other groups may also distribute 31 working documents as Internet-Drafts. The list of current Internet- 32 Drafts is at http://datatracker.ietf.org/drafts/current/. 34 Internet-Drafts are draft documents valid for a maximum of six months 35 and may be updated, replaced, or obsoleted by other documents at any 36 time. It is inappropriate to use Internet-Drafts as reference 37 material or to cite them other than as "work in progress." 39 This Internet-Draft will expire on May 3, 2017. 41 Copyright Notice 43 Copyright (c) 2016 IETF Trust and the persons identified as the 44 document authors. All rights reserved. 46 This document is subject to BCP 78 and the IETF Trust's Legal 47 Provisions Relating to IETF Documents 48 (http://trustee.ietf.org/license-info) in effect on the date of 49 publication of this document. Please review these documents 50 carefully, as they describe your rights and restrictions with respect 51 to this document. Code Components extracted from this document must 52 include Simplified BSD License text as described in Section 4.e of 53 the Trust Legal Provisions and are provided without warranty as 54 described in the Simplified BSD License. 56 Table of Contents 58 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 59 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4 60 3. Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 61 4. Motivation for a Performance Metrics Registry . . . . . . . . 7 62 4.1. Interoperability . . . . . . . . . . . . . . . . . . . . 7 63 4.2. Single point of reference for Performance Metrics . . . . 8 64 4.3. Side benefits . . . . . . . . . . . . . . . . . . . . . . 8 65 5. Criteria for Performance Metrics Registration . . . . . . . . 9 66 6. Performance Metric Registry: Prior attempt . . . . . . . . . 9 67 6.1. Why this Attempt Will Succeed . . . . . . . . . . . . . . 10 68 7. Definition of the Performance Metric Registry . . . . . . . . 10 69 7.1. Summary Category . . . . . . . . . . . . . . . . . . . . 12 70 7.1.1. Identifier . . . . . . . . . . . . . . . . . . . . . 12 71 7.1.2. Name . . . . . . . . . . . . . . . . . . . . . . . . 13 72 7.1.3. URIs . . . . . . . . . . . . . . . . . . . . . . . . 16 73 7.1.4. Description . . . . . . . . . . . . . . . . . . . . . 16 74 7.1.5. Reference . . . . . . . . . . . . . . . . . . . . . . 16 75 7.1.6. Change Controller . . . . . . . . . . . . . . . . . . 16 76 7.1.7. Version (of Registry Format) . . . . . . . . . . . . 16 77 7.2. Metric Definition Category . . . . . . . . . . . . . . . 17 78 7.2.1. Reference Definition . . . . . . . . . . . . . . . . 17 79 7.2.2. Fixed Parameters . . . . . . . . . . . . . . . . . . 17 80 7.3. Method of Measurement Category . . . . . . . . . . . . . 18 81 7.3.1. Reference Method . . . . . . . . . . . . . . . . . . 18 82 7.3.2. Packet Stream Generation . . . . . . . . . . . . . . 18 83 7.3.3. Traffic Filter . . . . . . . . . . . . . . . . . . . 19 84 7.3.4. Sampling Distribution . . . . . . . . . . . . . . . . 19 85 7.3.5. Run-time Parameters . . . . . . . . . . . . . . . . . 20 86 7.3.6. Role . . . . . . . . . . . . . . . . . . . . . . . . 20 87 7.4. Output Category . . . . . . . . . . . . . . . . . . . . . 21 88 7.4.1. Type . . . . . . . . . . . . . . . . . . . . . . . . 21 89 7.4.2. Reference Definition . . . . . . . . . . . . . . . . 21 90 7.4.3. Metric Units . . . . . . . . . . . . . . . . . . . . 21 91 7.4.4. Calibration . . . . . . . . . . . . . . . . . . . . . 21 92 7.5. Administrative information . . . . . . . . . . . . . . . 22 93 7.5.1. Status . . . . . . . . . . . . . . . . . . . . . . . 22 94 7.5.2. Requester . . . . . . . . . . . . . . . . . . . . . . 22 95 7.5.3. Revision . . . . . . . . . . . . . . . . . . . . . . 22 96 7.5.4. Revision Date . . . . . . . . . . . . . . . . . . . . 22 98 7.6. Comments and Remarks . . . . . . . . . . . . . . . . . . 23 99 8. The Life-Cycle of Registered Performance Metrics . . . . . . 23 100 8.1. Adding new Performance Metrics to the Performance Metrics 101 Registry . . . . . . . . . . . . . . . . . . . . . . . . 23 102 8.2. Revising Registered Performance Metrics . . . . . . . . . 24 103 8.3. Deprecating Registered Performance Metrics . . . . . . . 25 104 9. Security considerations . . . . . . . . . . . . . . . . . . . 26 105 10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 26 106 11. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 27 107 12. References . . . . . . . . . . . . . . . . . . . . . . . . . 28 108 12.1. Normative References . . . . . . . . . . . . . . . . . . 28 109 12.2. Informative References . . . . . . . . . . . . . . . . . 29 110 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 31 112 1. Introduction 114 The IETF specifies and uses Performance Metrics of protocols and 115 applications transported over its protocols. Performance metrics are 116 such an important part of the operations of IETF protocols that 117 [RFC6390] specifies guidelines for their development. 119 The definition and use of Performance Metrics in the IETF happens in 120 various working groups (WG), most notably: 122 The "IP Performance Metrics" (IPPM) WG is the WG primarily 123 focusing on Performance Metrics definition at the IETF. 125 The "Metric Blocks for use with RTCP's Extended Report Framework" 126 (XRBLOCK) WG recently specified many Performance Metrics related 127 to "RTP Control Protocol Extended Reports (RTCP XR)" [RFC3611], 128 which establishes a framework to allow new information to be 129 conveyed in RTCP, supplementing the original report blocks defined 130 in "RTP: A Transport Protocol for Real-Time Applications", 131 [RFC3550]. 133 The "Benchmarking Methodology" WG (BMWG) defined many Performance 134 Metrics for use in laboratory benchmarking of inter-networking 135 technologies. 137 The "IP Flow Information eXport" (IPFIX) concluded WG specified an 138 IANA process for new Information Elements. Some Performance 139 Metrics related Information Elements are proposed on regular 140 basis. 142 The "Performance Metrics for Other Layers" (PMOL) concluded WG, 143 defined some Performance Metrics related to Session Initiation 144 Protocol (SIP) voice quality [RFC6035]. 146 It is expected that more Performance Metrics will be defined in the 147 future, not only IP-based metrics, but also metrics which are 148 protocol-specific and application-specific. 150 However, despite the importance of Performance Metrics, there are two 151 related problems for the industry. First, how to ensure that when 152 one party requests another party to measure (or report or in some way 153 act on) a particular Performance Metric, then both parties have 154 exactly the same understanding of what Performance Metric is being 155 referred to. Second, how to discover which Performance Metrics have 156 been specified, so as to avoid developing new Performance Metric that 157 is very similar, but not quite inter-operable. The problems can be 158 addressed by creating a registry of performance metrics. The usual 159 way in which IETF organizes namespaces is with Internet Assigned 160 Numbers Authority (IANA) registries, and there is currently no 161 Performance Metrics Registry maintained by the IANA. 163 This document therefore requests that IANA create and maintain a 164 Performance Metrics Registry, according to the maintenance procedures 165 and the Performance Metrics Registry format defined in this memo. 166 Although the Registry format is primarily for use by IANA, any other 167 organization that wishes to create a Performance Metrics Registry MAY 168 use the same format for their purposes. The authors make no 169 guarantee of the format's applicability to any possible set of 170 Performance Metrics envisaged by other organizations, but encourage 171 others to apply it. In the remainder of this document, unless we 172 explicitly say so, we will refer to the IANA-maintained Performance 173 Metrics Registry as simply the Performance Metrics Registry. 175 2. Terminology 177 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 178 "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and 179 "OPTIONAL" in this document are to be interpreted as described in 180 [RFC2119]. 182 Performance Metric: A Performance Metric is a quantitative measure 183 of performance, targeted to an IETF-specified protocol or targeted 184 to an application transported over an IETF-specified protocol. 185 Examples of Performance Metrics are the FTP response time for a 186 complete file download, the DNS response time to resolve the IP 187 address, a database logging time, etc. This definition is 188 consistent with the definition of metric in [RFC2330] and broader 189 than the definition of performance metric in [RFC6390]. 191 Registered Performance Metric: A Registered Performance Metric is a 192 Performance Metric expressed as an entry in the Performance Metric 193 Registry, administered by IANA. Such a performance metric has met 194 all the registry review criteria defined in this document in order 195 to included in the registry. 197 Performance Metrics Registry: The IANA registry containing 198 Registered Performance Metrics. 200 Proprietary Registry: A set of metrics that are registered in a 201 proprietary registry, as opposed to Performance Metrics Registry. 203 Performance Metrics Experts: The Performance Metrics Experts is a 204 group of designated experts [RFC5226] selected by the IESG to 205 validate the Performance Metrics before updating the Performance 206 Metrics Registry. The Performance Metrics Experts work closely 207 with IANA. 209 Parameter: An input factor defined as a variable in the definition 210 of a Performance Metric. A numerical or other specified factor 211 forming one of a set that defines a metric or sets the conditions 212 of its operation. All Parameters must be known to measure using a 213 metric and interpret the results. There are two types of 214 Parameters, Fixed and Run-time parameters. For the Fixed 215 Parameters, the value of the variable is specified in the 216 Performance Metrics Registry entry and different Fixed Parameter 217 values results in different Registered Performance Metrics. For 218 the Run-time Parameters, the value of the variable is defined when 219 the metric measurement method is executed and a given Registered 220 Performance Metric supports multiple values for the parameter. 221 Although Run-time Parameters do not change the fundamental nature 222 of the Performance Metric's definition, some have substantial 223 influence on the network property being assessed and 224 interpretation of the results. 226 Note: Consider the case of packet loss in the following two 227 Active Measurement Method cases. The first case is packet loss 228 as background loss where the Run-time Parameter set includes a 229 very sparse Poisson stream, and only characterizes the times 230 when packets were lost. Actual user streams likely see much 231 higher loss at these times, due to tail drop or radio errors. 232 The second case is packet loss as inverse of throughput where 233 the Run-time Parameter set includes a very dense, bursty 234 stream, and characterizes the loss experienced by a stream that 235 approximates a user stream. These are both "loss metrics", but 236 the difference in interpretation of the results is highly 237 dependent on the Run-time Parameters (at least), to the extreme 238 where we are actually using loss to infer its compliment: 239 delivered throughput. 241 Active Measurement Method: Methods of Measurement conducted on 242 traffic which serves only the purpose of measurement and is 243 generated for that reason alone, and whose traffic characteristics 244 are known a priori. The complete definition of Active Methods is 245 specified in section 3.4 of[RFC7799]. Examples of Active 246 Measurement Methods are the measurement methods for the One way 247 delay metric defined in [RFC7679] and the one for round trip delay 248 defined in [RFC2681]. 250 Passive Measurement Method: Methods of Measurement conducted on 251 network traffic, generated either from the end users or from 252 network elements that would exist regardless whether the 253 measurement was being conducted or not. The complete definition 254 of Passive Methods is specified in section 3.6 of [RFC7799]. One 255 characteristic of Passive Measurement Methods is that sensitive 256 information may be observed, and as a consequence, stored in the 257 measurement system. 259 Hybrid Measurement Method: Hybrid Methods are Methods of Measurement 260 that use a combination of Active Methods and Passive Methods, to 261 assess Active Metrics, Passive Metrics, or new metrics derived 262 from the a priori knowledge and observations of the stream of 263 interest. The complete definition of Hybrid Methods is specified 264 in section 3.8 of [RFC7799]. 266 3. Scope 268 This document is meant mainly for two different audiences. For those 269 defining new Registered Performance Metrics, it provides 270 specifications and best practices to be used in deciding which 271 Registered Performance Metrics are useful for a measurement study, 272 instructions for writing the text for each column of the Registered 273 Performance Metrics, and information on the supporting documentation 274 required for the new Performance Metrics Registry entry (up to and 275 including the publication of one or more RFCs or I-Ds describing it). 276 For the appointed Performance Metrics Experts and for IANA personnel 277 administering the new IANA Performance Metric Registry, it defines a 278 set of acceptance criteria against which these proposed Registered 279 Performance Metrics should be evaluated. In addition, this document 280 may be useful for other organization who are defining a Performance 281 Metric registry of its own, who can rely on the Performance Metric 282 registry defined in this document. 284 This Performance Metric Registry is applicable to Performance Metrics 285 issued from Active Measurement, Passive Measurement, and any other 286 form of Performance Metric. This registry is designed to encompass 287 Performance Metrics developed throughout the IETF and especially for 288 the technologies specified in the following working groups: IPPM, 289 XRBLOCK, IPFIX, and BMWG. This document analyzes an prior attempt to 290 set up a Performance Metric Registry, and the reasons why this design 291 was inadequate [RFC6248]. Finally, this document gives a set of 292 guidelines for requesters and expert reviewers of candidate 293 Registered Performance Metrics. 295 This document makes no attempt to populate the Performance Metrics 296 Registry with initial entries. It does provides a few examples that 297 are merely illustrations and should not be included in the registry 298 at this point in time. 300 Based on [RFC5226] Section 4.3, this document is processed as Best 301 Current Practice (BCP) [RFC2026]. 303 4. Motivation for a Performance Metrics Registry 305 In this section, we detail several motivations for the Performance 306 Metric Registry. 308 4.1. Interoperability 310 As any IETF registry, the primary use for a registry is to manage a 311 namespace for its use within one or more protocols. In the 312 particular case of the Performance Metric Registry, there are two 313 types of protocols that will use the Performance Metrics in the 314 Performance Metrics Registry during their operation (by referring to 315 the Index values): 317 o Control protocol: this type of protocols is used to allow one 318 entity to request another entity to perform a measurement using a 319 specific metric defined by the Performance Metrics Registry. One 320 particular example is the LMAP framework [RFC7594]. Using the 321 LMAP terminology, the Performance Metrics Registry is used in the 322 LMAP Control protocol to allow a Controller to request a 323 measurement task to one or more Measurement Agents. In order to 324 enable this use case, the entries of the Performance Metric 325 Registry must be well enough defined to allow a Measurement Agent 326 implementation to trigger a specific measurement task upon the 327 reception of a control protocol message. This requirement heavily 328 constrains the type of entries that are acceptable for the 329 Performance Metric Registry. 331 o Report protocol: This type of protocols is used to allow an entity 332 to report measurement results to another entity. By referencing 333 to a specific Performance Metric Registry, it is possible to 334 properly characterize the measurement result data being reported. 335 Using the LMAP terminology, the Performance Metrics Registry is 336 used in the Report protocol to allow a Measurement Agent to report 337 measurement results to a Collector. 339 It should be noted that the LMAP framework explicitly allows for 340 using not only the IANA-maintained Performance Metrics Registry but 341 also other registries containing Performance Metrics, either defined 342 by other organizations or private ones. However, others who are 343 creating Registries to be used in the context of an LMAP framework 344 are encouraged to use the Registry format defined in this document, 345 because this makes it easier for developers of LMAP Measurement 346 Agents (MAs) to programmatically use information found in those other 347 Registries' entries. 349 4.2. Single point of reference for Performance Metrics 351 A Performance Metrics Registry serves as a single point of reference 352 for Performance Metrics defined in different working groups in the 353 IETF. As we mentioned earlier, there are several WGs that define 354 Performance Metrics in the IETF and it is hard to keep track of all 355 them. This results in multiple definitions of similar Performance 356 Metrics that attempt to measure the same phenomena but in slightly 357 different (and incompatible) ways. Having a registry would allow 358 both the IETF community and external people to have a single list of 359 relevant Performance Metrics defined by the IETF (and others, where 360 appropriate). The single list is also an essential aspect of 361 communication about Performance Metrics, where different entities 362 that request measurements, execute measurements, and report the 363 results can benefit from a common understanding of the referenced 364 Performance Metric. 366 4.3. Side benefits 368 There are a couple of side benefits of having such a registry. 369 First, the Performance Metrics Registry could serve as an inventory 370 of useful and used Performance Metrics, that are normally supported 371 by different implementations of measurement agents. Second, the 372 results of measurements using the Performance Metrics would be 373 comparable even if they are performed by different implementations 374 and in different networks, as the Performance Metric is properly 375 defined. BCP 176 [RFC6576] examines whether the results produced by 376 independent implementations are equivalent in the context of 377 evaluating the completeness and clarity of metric specifications. 378 This BCP defines the standards track advancement testing for (active) 379 IPPM metrics, and the same process will likely suffice to determine 380 whether Registered Performance Metrics are sufficiently well 381 specified to result in comparable (or equivalent) results. 382 Registered Performance Metrics which have undergone such testing 383 SHOULD be noted, with a reference to the test results. 385 5. Criteria for Performance Metrics Registration 387 It is neither possible nor desirable to populate the Performance 388 Metrics Registry with all combinations of Parameters of all 389 Performance Metrics. The Registered Performance Metrics should be: 391 1. interpretable by the user. 393 2. implementable by the software designer, 395 3. deployable by network operators, 397 4. accurate, for interoperability and deployment across vendors, 399 5. Operationally useful, so that it has significant industry 400 interest and/or has seen deployment, 402 6. Sufficiently tightly defined, so that different values for the 403 Run-time Parameters does not change the fundamental nature of the 404 measurement, nor change the practicality of its implementation. 406 In essence, there needs to be evidence that a candidate Registered 407 Performance Metric has significant industry interest, or has seen 408 deployment, and there is agreement that the candidate Registered 409 Performance Metric serves its intended purpose. 411 6. Performance Metric Registry: Prior attempt 413 There was a previous attempt to define a metric registry RFC 4148 414 [RFC4148]. However, it was obsoleted by RFC 6248 [RFC6248] because 415 it was "found to be insufficiently detailed to uniquely identify IPPM 416 metrics... [there was too much] variability possible when 417 characterizing a metric exactly" which led to the RFC4148 registry 418 having "very few users, if any". 420 A couple of interesting additional quotes from RFC 6248 might help 421 understand the issues related to that registry. 423 1. "It is not believed to be feasible or even useful to register 424 every possible combination of Type P, metric parameters, and 425 Stream parameters using the current structure of the IPPM Metrics 426 Registry." 428 2. "The registry structure has been found to be insufficiently 429 detailed to uniquely identify IPPM metrics." 431 3. "Despite apparent efforts to find current or even future users, 432 no one responded to the call for interest in the RFC 4148 433 registry during the second half of 2010." 435 The current approach learns from this by tightly defining each 436 Registered Performance Metric with only a few variable (Run-time) 437 Parameters to be specified by the measurement designer, if any. The 438 idea is that entries in the Performance Metrics Registry stem from 439 different measurement methods which require input (Run-time) 440 parameters to set factors like source and destination addresses 441 (which do not change the fundamental nature of the measurement). The 442 downside of this approach is that it could result in a large number 443 of entries in the Performance Metrics Registry. There is agreement 444 that less is more in this context - it is better to have a reduced 445 set of useful metrics rather than a large set of metrics, some with 446 with questionable usefulness. 448 6.1. Why this Attempt Will Succeed 450 As mentioned in the previous section, one of the main issues with the 451 previous registry was that the metrics contained in the registry were 452 too generic to be useful. This document specifies stricter criteria 453 for performance metric registration (see section 6), and imposes a 454 group of Performance Metrics Experts that will provide guidelines to 455 assess if a Performance Metric is properly specified. 457 Another key difference between this attempt and the previous one is 458 that in this case there is at least one clear user for the 459 Performance Metrics Registry: the LMAP framework and protocol. 460 Because the LMAP protocol will use the Performance Metrics Registry 461 values in its operation, this actually helps to determine if a metric 462 is properly defined. In particular, since we expect that the LMAP 463 control protocol will enable a controller to request a measurement 464 agent to perform a measurement using a given metric by embedding the 465 Performance Metric Registry value in the protocol, a metric is 466 properly specified if it is defined well-enough so that it is 467 possible (and practical) to implement the metric in the measurement 468 agent. This was the failure of the previous attempt: a registry 469 entry with an undefined Type-P (section 13 of RFC 2330 [RFC2330]) 470 allows implementation to be ambiguous. 472 7. Definition of the Performance Metric Registry 474 This Performance Metric Registry is applicable to Performance Metrics 475 used for Active Measurement, Passive Measurement, and any other form 476 of Performance Metric. Each category of measurement has unique 477 properties, so some of the columns defined below are not applicable 478 for a given metric category. In this case, the column(s) SHOULD be 479 populated with the "NA" value (Non Applicable). However, the "NA" 480 value MUST NOT be used by any metric in the following columns: 481 Identifier, Name, URI, Status, Requester, Revision, Revision Date, 482 Description. In the future, a new category of metrics could require 483 additional columns, and adding new columns is a recognized form of 484 registry extension. The specification defining the new column(s) 485 MUST give guidelines to populate the new column(s) for existing 486 entries (in general). 488 The columns of the Performance Metric Registry are defined below. 489 The columns are grouped into "Categories" to facilitate the use of 490 the registry. Categories are described at the 7.x heading level, and 491 columns are at the 7.x.y heading level. The Figure below illustrates 492 this organization. An entry (row) therefore gives a complete 493 description of a Registered Performance Metric. 495 Each column serves as a check-list item and helps to avoid omissions 496 during registration and expert review. 498 Registry Categories and Columns, shown as 500 Category 501 ------------------ 502 Column | Column | 504 Summary 505 ------------------------------------------------------------------------ 506 Identifier | Name | URIs | Desc. | Reference | Change Controller | Ver | 508 Metric Definition 509 ----------------------------------------- 510 Reference Definition | Fixed Parameters | 512 Method of Measurement 513 --------------------------------------------------------------------- 514 Reference | Packet | Traffic | Sampling | Run-time | Role | 515 Method | Stream | Filter | Distribution | Parameters | | 516 | Generation | 517 Output 518 ----------------------------------------- 519 Type | Reference | Units | Calibration | 520 | Definition | | | 522 Administrative Information 523 ---------------------------------- 524 Status |Request | Rev | Rev.Date | 526 Comments and Remarks 527 -------------------- 529 7.1. Summary Category 531 7.1.1. Identifier 533 A numeric identifier for the Registered Performance Metric. This 534 identifier MUST be unique within the Performance Metric Registry. 536 The Registered Performance Metric unique identifier is a 16-bit 537 integer (range 0 to 65535). 539 The Identifier 0 should be Reserved. The Identifier values from 540 64512 to 65536 are reserved for private use. 542 When adding newly Registered Performance Metrics to the Performance 543 Metric Registry, IANA should assign the lowest available identifier 544 to the next Registered Performance Metric. 546 7.1.2. Name 548 As the name of a Registered Performance Metric is the first thing a 549 potential human implementor will use when determining whether it is 550 suitable for their measurement study, it is important to be as 551 precise and descriptive as possible. In future, users will review 552 the names to determine if the metric they want to measure has already 553 been registered, or if a similar entry is available as a basis for 554 creating a new entry. 556 Names are composed of the following elements, separated by an 557 underscore character "_": 559 MetricType_Method_SubTypeMethod_... Spec_Units_Output 561 o MetricType: a combination of the directional properties and the 562 metric measured, such as: 564 RTDelay 566 RTDNS 568 OWDelay 570 RTLoss 572 OWLoss 574 OWPDV 576 OWIPDV 578 OWReorder 580 OWDuplic 582 OWBTC 584 OWMBM 586 SPMonitor (Single Point Monitor) 588 MPMonitor (Multi-Point Monitor) 590 o Method: One of the methods defined in [RFC7799], such as: 592 Active 593 Passive 595 HybridType1 597 HybridType2 599 Spatial 601 o SubTypeMethod: One or more sub-types to further describe the 602 features of the entry, such as: 604 ICMP 606 IP 608 DSCPxx (where xx is replaced by a decimal code point) 610 UDP 612 TCP 614 Poisson 616 Periodic 618 PayloadxxxxB (where xxxx is replaced by an integer) 620 SustainedBurst 622 StandingQueue 624 @@@@ 626 SubTypeMethod values are separated by a hyphen "-" character, 627 which indicates that they belong to this element, and that their 628 order is unimportant when considering name uniqueness. 630 o Spec: RFC that specifies this entry in the form RFCXXXXsecY, such 631 as RFC7799sec3. Note: this is not the Primary Reference 632 specification for the metric; it will be blank until the RFC 633 number is assigned, and would remain blank in private registry 634 entries without an RFC. 636 o Units: The units of measurement for the output, such as: 638 Seconds 640 RatioPercent (value multiplied by 100) 641 BPS (Bits per Second) 643 EventTotal (for unit-less counts) 645 Multiple 647 Enumerated 649 Unit-less 651 o Output: The type of output resulting from measurement, such as: 653 Singleton (sometimes called raw data) 655 Minimum 657 Maximum 659 Median 661 Mean 663 95Percentile 665 99Percentile 667 StdDev 669 PFI (Pass, Fail, Inconclusive) 671 FlowRecords 673 An example is: 675 RTDelay_Active_IP-UDP-Poisson_RFCXXXXsecY_Seconds_95percentile 677 as described in section 4 of [I-D.ietf-ippm-initial-registry]. 679 Note that private registries following the format described here 680 SHOULD use the prefix "Priv_" on any name to avoid unintended 681 conflicts (further considerations are described in section 10). 682 Private registry entries usually have no specifying RFC, thus the 683 Spec: element has no clear interpretation. 685 7.1.3. URIs 687 The URIs column MUST contain a URI [RFC3986] that uniquely identifies 688 the metric. This URI is a URN [RFC2141]. The URI is automatically 689 generated by prepending the prefix 691 urn:ietf:metric: 693 to the metric name. The resulting URI is globally unique. 695 The URIs column MUST contain a second URI which is a URL [RFC3986] 696 and uniquely identifies and locates the metric entry so it is 697 accessible through the Internet. The URL points to a file containing 698 the human-readable information of exactly one registry entry. 699 Ideally, the file will be HTML-formated and contain URLs to 700 referenced sections of HTML-ized RFCs. The separate files for 701 different entries can be more easily edited and re-used when 702 preparing new entries. The exact composition of each metric URL will 703 be determined by IANA and reside on "iana.org", but there will be 704 some overlap with the URN described above. The major sections of 705 [I-D.ietf-ippm-initial-registry] provide an example in HTML form 706 (sections 4 and above). 708 7.1.4. Description 710 A Registered Performance Metric description is a written 711 representation of a particular Performance Metrics Registry entry. 712 It supplements the Registered Performance Metric name to help 713 Performance Metrics Registry users select relevant Registered 714 Performance Metrics. 716 7.1.5. Reference 718 This entry gives the specification containing the candidate registry 719 entry which was reviewed and agreed, if such an RFC or other 720 specification exists. 722 7.1.6. Change Controller 724 This entry names the entity responsible for approving revsions to the 725 regsitry entry, and provides contact information. 727 7.1.7. Version (of Registry Format) 729 This entry gives the version number for the registry format used. 730 Formats complying with this memo MUST use 1.0. 732 7.2. Metric Definition Category 734 This category includes columns to prompt all necessary details 735 related to the metric definition, including the RFC reference and 736 values of input factors, called fixed parameters, which are left open 737 in the RFC but have a particular value defined by the performance 738 metric. 740 7.2.1. Reference Definition 742 This entry provides a reference (or references) to the relevant 743 section(s) of the document(s) that define the metric, as well as any 744 supplemental information needed to ensure an unambiguous definition 745 for implementations. The reference needs to be an immutable 746 document, such as an RFC; for other standards bodies, it is likely to 747 be necessary to reference a specific, dated version of a 748 specification. 750 7.2.2. Fixed Parameters 752 Fixed Parameters are Parameters whose value must be specified in the 753 Performance Metrics Registry. The measurement system uses these 754 values. 756 Where referenced metrics supply a list of Parameters as part of their 757 descriptive template, a sub-set of the Parameters will be designated 758 as Fixed Parameters. For example, for active metrics, Fixed 759 Parameters determine most or all of the IPPM Framework convention 760 "packets of Type-P" as described in [RFC2330], such as transport 761 protocol, payload length, TTL, etc. An example for passive metrics 762 is for RTP packet loss calculation that relies on the validation of a 763 packet as RTP which is a multi-packet validation controlled by 764 MIN_SEQUENTIAL as defined by [RFC3550]. Varying MIN_SEQUENTIAL 765 values can alter the loss report and this value could be set as a 766 Fixed Parameter. 768 Parameters MUST have well defined names. For human readers, the 769 hanging indent style is preferred, and the names and definitions that 770 do not appear in the Reference Method Specification MUST appear in 771 this column. 773 Parameters MUST have a well-specified data format. 775 A Parameter which is a Fixed Parameter for one Performance Metrics 776 Registry entry may be designated as a Run-time Parameter for another 777 Performance Metrics Registry entry. 779 7.3. Method of Measurement Category 781 This category includes columns for references to relevant sections of 782 the RFC(s) and any supplemental information needed to ensure an 783 unambiguous method for implementations. 785 7.3.1. Reference Method 787 This entry provides references to relevant sections of the RFC(s) 788 describing the method of measurement, as well as any supplemental 789 information needed to ensure unambiguous interpretation for 790 implementations referring to the RFC text. 792 Specifically, this section should include pointers to pseudocode or 793 actual code that could be used for an unambigious implementation. 795 7.3.2. Packet Stream Generation 797 This column applies to Performance Metrics that generate traffic for 798 a part of their Measurement Method purposes including but not 799 necessarily limited to Active metrics. The generated traffic is 800 referred as stream and this columns describe its characteristics. 802 Each entry for this column contains the following information: 804 o Value: The name of the packet stream scheduling discipline 806 o Reference: the specification where the stream is defined 808 The packet generation stream may require parameters such as the the 809 average packet rate and distribution truncation value for streams 810 with Poisson-distributed inter-packet sending times. In case such 811 parameters are needed, they should be included either in the Fixed 812 parameter column or in the run time parameter column, depending on 813 wether they will be fixed or will be an input for the metric. 815 The simplest example of stream specification is Singleton scheduling 816 (see [RFC2330]), where a single atomic measurement is conducted. 817 Each atomic measurement could consist of sending a single packet 818 (such as a DNS request) or sending several packets (for example, to 819 request a webpage). Other streams support a series of atomic 820 measurements in a "sample", with a schedule defining the timing 821 between each transmitted packet and subsequent measurement. 822 Principally, two different streams are used in IPPM metrics, Poisson 823 distributed as described in [RFC2330] and Periodic as described in 824 [RFC3432]. Both Poisson and Periodic have their own unique 825 parameters, and the relevant set of parameters names and values 826 should be included either in the Fixed Parameters column or in the 827 Run-time parameter column. 829 7.3.3. Traffic Filter 831 This column applies to Performance Metrics that observe packets 832 flowing through (the device with) the measurement agent i.e. that is 833 not necessarily addressed to the measurement agent. This includes 834 but is not limited to Passive Metrics. The filter specifies the 835 traffic that is measured. This includes protocol field values/ 836 ranges, such as address ranges, and flow or session identifiers. 838 The traffic filter itself depends on needs of the metric itself and a 839 balance of operators measurement needs and user's need for privacy. 840 Mechanics for conveying the filter criteria might be the BPF (Berkley 841 Packet Filter) or PSAMP [RFC5475] Property Match Filtering which 842 reuses IPFIX [RFC7012]. An example BPF string for matching TCP/80 843 traffic to remote destination net 192.0.2.0/24 would be "dst net 844 192.0.2.0/24 and tcp dst port 80". More complex filter engines might 845 be supported by the implementation that might allow for matching 846 using Deep Packet Inspection (DPI) technology. 848 The traffic filter includes the following information: 850 Type: the type of traffic filter used, e.g. BPF, PSAMP, OpenFlow 851 rule, etc. as defined by a normative reference 853 Value: the actual set of rules expressed 855 7.3.4. Sampling Distribution 857 The sampling distribution defines out of all the packets that match 858 the traffic filter, which one of those are actually used for the 859 measurement. One possibility is "all" which implies that all packets 860 matching the Traffic filter are considered, but there may be other 861 sampling strategies. It includes the following information: 863 Value: the name of the sampling distribution 865 Reference definition: pointer to the specification where the 866 sampling distribution is properly defined. 868 The sampling distribution may require parameters. In case such 869 parameters are needed, they should be included either in the Fixed 870 parameter column or in the run time parameter column, depending on 871 wether they will be fixed or will be an input for the metric. 873 Sampling and Filtering Techniques for IP Packet Selection are 874 documented in the PSAMP (Packet Sampling) [RFC5475], while the 875 Framework for Packet Selection and Reporting, [RFC5474] provides more 876 background information. The sampling distribution parameters might 877 be expressed in terms of the Information Model for Packet Sampling 878 Exports, [RFC5477], and the Flow Selection Techniques, [RFC7014]. 880 7.3.5. Run-time Parameters 882 Run-Time Parameters are Parameters that must be determined, 883 configured into the measurement system, and reported with the results 884 for the context to be complete. However, the values of these 885 parameters is not specified in the Performance Metrics Registry (like 886 the Fixed Parameters), rather these parameters are listed as an aid 887 to the measurement system implementer or user (they must be left as 888 variables, and supplied on execution). 890 Where metrics supply a list of Parameters as part of their 891 descriptive template, a sub-set of the Parameters will be designated 892 as Run-Time Parameters. 894 Parameters MUST have well defined names. For human readers, the 895 hanging indent style is preferred, and the names and definitions that 896 do not appear in the Reference Method Specification MUST appear in 897 this column. 899 A Data Format for each Run-time Parameter MUST be specified in this 900 column, to simplify the control and implementation of measurement 901 devices. For example, parameters that include an IPv4 address can be 902 encoded as a 32 bit integer (i.e. binary base64 encoded value) or ip- 903 address as defined in [RFC6991]. The actual encoding(s) used must be 904 explicitly defined for each Run-time parameter. IPv6 addresses and 905 options MUST be accomodated, allowing Registered Metrics to be used 906 in either address family. 908 Examples of Run-time Parameters include IP addresses, measurement 909 point designations, start times and end times for measurement, and 910 other information essential to the method of measurement. 912 7.3.6. Role 914 In some method of measurements, there may be several roles defined 915 e.g. on a one-way packet delay active measurement, there is one 916 measurement agent that generates the packets and the other one that 917 receives the packets. This column contains the name of the role for 918 this particular entry. In the previous example, there should be two 919 entries in the registry, one for each role, so that when a 920 measurement agent is instructed to perform the one way delay source 921 metric know that it is supposed to generate packets. The values for 922 this field are defined in the reference method of measurement. 924 7.4. Output Category 926 For entries which involve a stream and many singleton measurements, a 927 statistic may be specified in this column to summarize the results to 928 a single value. If the complete set of measured singletons is 929 output, this will be specified here. 931 Some metrics embed one specific statistic in the reference metric 932 definition, while others allow several output types or statistics. 934 7.4.1. Type 936 This column contains the name of the output type. The output type 937 defines a single type of result that the metric produces. It can be 938 the raw results (packet send times and singleton metrics), or it can 939 be a summary statistic. The specification of the output type MUST 940 define the format of the output. In some systems, format 941 specifications will simplify both measurement implementation and 942 collection/storage tasks. Note that if two different statistics are 943 required from a single measurement (for example, both "Xth percentile 944 mean" and "Raw"), then a new output type must be defined ("Xth 945 percentile mean AND Raw"). See the Naming section above for a list 946 of Output Types. 948 7.4.2. Reference Definition 950 This column contains a pointer to the specification(s) where the 951 output type and format are defined. 953 7.4.3. Metric Units 955 The measured results must be expressed using some standard dimension 956 or units of measure. This column provides the units. 958 When a sample of singletons (see Section 11 of[RFC2330] for 959 definitions of these terms) is collected, this entry will specify the 960 units for each measured value. 962 7.4.4. Calibration 964 Some specifications for Methods of Measurement include the 965 possibility to perform an error calibration. Section 3.7.3 of 966 [RFC7679] is one example. In the registry entry, this field will 967 identify a method of calibration for the metric, and when available, 968 the measurement system SHOULD perform the calibration when requested 969 and produce the output with an indication that it is the restult of a 970 calbration method. In-situ calibration could be enabled with an 971 internal loopback that includes as much of the measurement system as 972 possible, performs address manipulation as needed, and provides some 973 form of isolation (e.g., deterministic delay) to avoid send-receive 974 interface contention. Some portion of the random and systematic 975 error can be characterized this way. 977 For one-way delay measurements, the error calibration must include an 978 assessment of the internal clock synchronization with its external 979 reference (this internal clock is supplying timestamps for 980 measurement). In practice, the time offsets of clocks at both the 981 source and destination are needed to estimate the systematic error 982 due to imperfect clock synchronization (the time offsets are 983 smoothed, thus the random variation is not usually represented in the 984 results). 986 Both internal loopback calibration and clock synchronization can be 987 used to estimate the *available accuracy* of the Output Metric Units. 988 For example, repeated loopback delay measurements will reveal the 989 portion of the Output result resolution which is the result of system 990 noise, and thus inaccurate. 992 7.5. Administrative information 994 7.5.1. Status 996 The status of the specification of this Registered Performance 997 Metric. Allowed values are 'current' and 'deprecated'. All newly 998 defined Information Elements have 'current' status. 1000 7.5.2. Requester 1002 The requester for the Registered Performance Metric. The requester 1003 MAY be a document, such as RFC, or person. 1005 7.5.3. Revision 1007 The revision number of a Registered Performance Metric, starting at 0 1008 for Registered Performance Metrics at time of definition and 1009 incremented by one for each revision. 1011 7.5.4. Revision Date 1013 The date of acceptance or the most recent revision for the Registered 1014 Performance Metric. 1016 7.6. Comments and Remarks 1018 Besides providing additional details which do not appear in other 1019 categories, this open Category (single column) allows for unforeseen 1020 issues to be addressed by simply updating this informational entry. 1022 8. The Life-Cycle of Registered Performance Metrics 1024 Once a Performance Metric or set of Performance Metrics has been 1025 identified for a given application, candidate Performance Metrics 1026 Registry entry specifications in accordance with Section 7 are 1027 submitted to IANA to follow the process for review by the Performance 1028 Metric Experts, as defined below. This process is also used for 1029 other changes to the Performance Metric Registry, such as deprecation 1030 or revision, as described later in this section. 1032 It is also desirable that the author(s) of a candidate Performance 1033 Metrics Registry entry seek review in the relevant IETF working 1034 group, or offer the opportunity for review on the WG mailing list. 1036 8.1. Adding new Performance Metrics to the Performance Metrics Registry 1038 Requests to change Registered Performance Metrics in the Performance 1039 Metric Registry are submitted to IANA, which forwards the request to 1040 a designated group of experts (Performance Metric Experts) appointed 1041 by the IESG; these are the reviewers called for by the Expert Review 1042 RFC5226 policy defined for the Performance Metric Registry. The 1043 Performance Metric Experts review the request for such things as 1044 compliance with this document, compliance with other applicable 1045 Performance Metric-related RFCs, and consistency with the currently 1046 defined set of Registered Performance Metrics. 1048 Authors are expected to review compliance with the specifications in 1049 this document to check their submissions before sending them to IANA. 1051 The Performance Metric Experts should endeavor to complete referred 1052 reviews in a timely manner. If the request is acceptable, the 1053 Performance Metric Experts signify their approval to IANA, which 1054 updates the Performance Metric Registry. If the request is not 1055 acceptable, the Performance Metric Experts can coordinate with the 1056 requester to change the request to be compliant. The Performance 1057 Metric Experts may also choose in exceptional circumstances to reject 1058 clearly frivolous or inappropriate change requests outright. 1060 This process should not in any way be construed as allowing the 1061 Performance Metric Experts to overrule IETF consensus. Specifically, 1062 any Registered Performance Metrics that were added with IETF 1063 consensus require IETF consensus for revision or deprecation. 1065 Decisions by the Performance Metric Experts may be appealed as in 1066 Section 7 of RFC5226. 1068 8.2. Revising Registered Performance Metrics 1070 A request for Revision is only permissible when the changes maintain 1071 backward-compatibility with implementations of the prior Performance 1072 Metrics Registry entry describing a Registered Performance Metric 1073 (entries with lower revision numbers, but the same Identifier and 1074 Name). 1076 The purpose of the Status field in the Performance Metric Registry is 1077 to indicate whether the entry for a Registered Performance Metric is 1078 'current' or 'deprecated'. 1080 In addition, no policy is defined for revising the Performance Metric 1081 entries in the IANA Regsirty or addressing errors therein. To be 1082 certain, changes and deprecations within the Performance Metric 1083 Registry are not encouraged, and should be avoided to the extent 1084 possible. However, in recognition that change is inevitable, the 1085 provisions of this section address the need for revisions. 1087 Revisions are initiated by sending a candidate Registered Performance 1088 Metric definition to IANA, as in Section 8, identifying the existing 1089 Performance Metrics Registry entry. 1091 The primary requirement in the definition of a policy for managing 1092 changes to existing Registered Performance Metrics is avoidance of 1093 interoperability problems; Performance Metric Experts must work to 1094 maintain interoperability above all else. Changes to Registered 1095 Performance Metrics may only be done in an inter-operable way; 1096 necessary changes that cannot be done in a way to allow 1097 interoperability with unchanged implementations must result in the 1098 creation of a new Registered Performance Metric and possibly the 1099 deprecation of the earlier metric. 1101 A change to a Registered Performance Metric is held to be backward- 1102 compatible only when: 1104 1. "it involves the correction of an error that is obviously only 1105 editorial; or" 1107 2. "it corrects an ambiguity in the Registered Performance Metric's 1108 definition, which itself leads to issues severe enough to prevent 1109 the Registered Performance Metric's usage as originally defined; 1110 or" 1112 3. "it corrects missing information in the metric definition without 1113 changing its meaning (e.g., the explicit definition of 'quantity' 1114 semantics for numeric fields without a Data Type Semantics 1115 value); or" 1117 4. "it harmonizes with an external reference that was itself 1118 corrected." 1120 If an Performance Metric revision is deemed permissible by the 1121 Performance Metric Experts, according to the rules in this document, 1122 IANA makes the change in the Performance Metric Registry. The 1123 requester of the change is appended to the requester in the 1124 Performance Metrics Registry. 1126 Each Registered Performance Metric in the Performance Metrics 1127 Registry has a revision number, starting at zero. Each change to a 1128 Registered Performance Metric following this process increments the 1129 revision number by one. 1131 When a revised Registered Performance Metric is accepted into the 1132 Performance Metric Registry, the date of acceptance of the most 1133 recent revision is placed into the revision Date column of the 1134 registry for that Registered Performance Metric. 1136 Where applicable, additions to Registered Performance Metrics in the 1137 form of text Comments or Remarks should include the date, but such 1138 additions may not constitute a revision according to this process. 1140 Older version(s) of the updated metric entries are kept in the 1141 registry for archival purposes. The older entries are kept with all 1142 fields unmodified (version, revision date) except for the status 1143 field that is changed to "Deprecated". 1145 8.3. Deprecating Registered Performance Metrics 1147 Changes that are not permissible by the above criteria for Registered 1148 Performance Metric's revision may only be handled by deprecation. A 1149 Registered Performance Metric MAY be deprecated and replaced when: 1151 1. "the Registered Performance Metric definition has an error or 1152 shortcoming that cannot be permissibly changed as in 1153 Section Revising Registered Performance Metrics; or" 1155 2. "the deprecation harmonizes with an external reference that was 1156 itself deprecated through that reference's accepted deprecation 1157 method; or" 1159 A request for deprecation is sent to IANA, which passes it to the 1160 Performance Metric Expert for review. When deprecating an 1161 Performance Metric, the Performance Metric description in the 1162 Performance Metric Registry must be updated to explain the 1163 deprecation, as well as to refer to any new Performance Metrics 1164 created to replace the deprecated Performance Metric. 1166 The revision number of a Registered Performance Metric is incremented 1167 upon deprecation, and the revision Date updated, as with any 1168 revision. 1170 The use of deprecated Registered Performance Metrics should result in 1171 a log entry or human-readable warning by the respective application. 1173 Names and Metric ID of deprecated Registered Performance Metrics must 1174 not be reused. 1176 The deprecated entries are kept with all fields unmodified, except 1177 the version, revision date, and the status field (changed to 1178 "Deprecated"). 1180 9. Security considerations 1182 This draft doesn't introduce any new security considerations for the 1183 Internet. However, the definition of Performance Metrics may 1184 introduce some security concerns, and should be reviewed with 1185 security in mind. 1187 10. IANA Considerations 1189 This document specifies the procedure for Performance Metrics 1190 Registry setup. IANA is requested to create a new registry for 1191 Performance Metrics called "Registered Performance Metrics". This 1192 Registry will contain the following Summary columns: 1194 Identifier: 1196 Name: 1198 URIs: 1200 Description: 1202 Reference: 1204 Change Controller: 1206 Version: 1208 Descriptions of these columns and additional information found in the 1209 template for registry entries (categories and columns) are further 1210 defined in section Section 7. 1212 The "Identifier" 0 should be Reserved. "The Identifier" values from 1213 64512 to 65536 are reserved for private use. 1215 Names starting with the prefix Priv_ are reserved for private use, 1216 and are not considered for registration. The "Name" column entries 1217 are further defined in section Section 7. 1219 The "URIs" column will have a link to the full template. 1221 The "Reference" column will include an RFC, an approved specification 1222 from another standards body, or the contact person. 1224 New assignments for Performance Metric Registry will be administered 1225 by IANA through Expert Review [RFC5226], i.e., review by one of a 1226 group of experts, the Performance Metric Experts, who are appointed 1227 by the IESG upon recommendation of the Transport Area Directors. The 1228 experts can be initially drawn from the Working Group Chairs and 1229 document editors of the Performance Metrics Directorate among other 1230 sources of experts. 1232 This document requests the allocation of the URI prefix 1233 urn:ietf:metric: for the purpose of generating URIs for Registered 1234 Performance Metrics. 1236 Extensions of the Registry require IETF Standards Action. Two forms 1237 of registry extension are envisaged: 1239 1. Adding columns or both categories and columns, to accommodate 1240 unanticipated aspects of new measurements and metric categories. 1242 2. Additional values for the various elements used in the Metric 1243 "Name" column. A candidate Metric Entry RFC would propose one or 1244 more new element values required to describe the entry. 1246 11. Acknowledgments 1248 Thanks to Brian Trammell and Bill Cerveny, IPPM chairs, for leading 1249 some brainstorming sessions on this topic. Thanks to Barbara Stark 1250 and Juergen Schoenwaelder for the detailed feedback and suggestions. 1251 Thanks to Andrew McGregor for suggestions on metric naming. Thanks 1252 to Michelle Cotton for her early IANA review, and to Amanda Barber 1253 for answering questions related to the presentation of the registry 1254 and accessibility of the complete template via URL. 1256 12. References 1258 12.1. Normative References 1260 [RFC2026] Bradner, S., "The Internet Standards Process -- Revision 1261 3", BCP 9, RFC 2026, DOI 10.17487/RFC2026, October 1996, 1262 . 1264 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 1265 Requirement Levels", BCP 14, RFC 2119, 1266 DOI 10.17487/RFC2119, March 1997, 1267 . 1269 [RFC2141] Moats, R., "URN Syntax", RFC 2141, DOI 10.17487/RFC2141, 1270 May 1997, . 1272 [RFC2330] Paxson, V., Almes, G., Mahdavi, J., and M. Mathis, 1273 "Framework for IP Performance Metrics", RFC 2330, 1274 DOI 10.17487/RFC2330, May 1998, 1275 . 1277 [RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform 1278 Resource Identifier (URI): Generic Syntax", STD 66, 1279 RFC 3986, DOI 10.17487/RFC3986, January 2005, 1280 . 1282 [RFC4148] Stephan, E., "IP Performance Metrics (IPPM) Metrics 1283 Registry", BCP 108, RFC 4148, DOI 10.17487/RFC4148, August 1284 2005, . 1286 [RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an 1287 IANA Considerations Section in RFCs", BCP 26, RFC 5226, 1288 DOI 10.17487/RFC5226, May 2008, 1289 . 1291 [RFC6248] Morton, A., "RFC 4148 and the IP Performance Metrics 1292 (IPPM) Registry of Metrics Are Obsolete", RFC 6248, 1293 DOI 10.17487/RFC6248, April 2011, 1294 . 1296 [RFC6390] Clark, A. and B. Claise, "Guidelines for Considering New 1297 Performance Metric Development", BCP 170, RFC 6390, 1298 DOI 10.17487/RFC6390, October 2011, 1299 . 1301 [RFC6576] Geib, R., Ed., Morton, A., Fardid, R., and A. Steinmitz, 1302 "IP Performance Metrics (IPPM) Standard Advancement 1303 Testing", BCP 176, RFC 6576, DOI 10.17487/RFC6576, March 1304 2012, . 1306 12.2. Informative References 1308 [RFC2679] Almes, G., Kalidindi, S., and M. Zekauskas, "A One-way 1309 Delay Metric for IPPM", RFC 2679, DOI 10.17487/RFC2679, 1310 September 1999, . 1312 [RFC7679] Almes, G., Kalidindi, S., Zekauskas, M., and A. Morton, 1313 Ed., "A One-Way Delay Metric for IP Performance Metrics 1314 (IPPM)", STD 81, RFC 7679, DOI 10.17487/RFC7679, January 1315 2016, . 1317 [RFC2681] Almes, G., Kalidindi, S., and M. Zekauskas, "A Round-trip 1318 Delay Metric for IPPM", RFC 2681, DOI 10.17487/RFC2681, 1319 September 1999, . 1321 [RFC3393] Demichelis, C. and P. Chimento, "IP Packet Delay Variation 1322 Metric for IP Performance Metrics (IPPM)", RFC 3393, 1323 DOI 10.17487/RFC3393, November 2002, 1324 . 1326 [RFC3432] Raisanen, V., Grotefeld, G., and A. Morton, "Network 1327 performance measurement with periodic streams", RFC 3432, 1328 DOI 10.17487/RFC3432, November 2002, 1329 . 1331 [RFC3550] Schulzrinne, H., Casner, S., Frederick, R., and V. 1332 Jacobson, "RTP: A Transport Protocol for Real-Time 1333 Applications", STD 64, RFC 3550, DOI 10.17487/RFC3550, 1334 July 2003, . 1336 [RFC3611] Friedman, T., Ed., Caceres, R., Ed., and A. Clark, Ed., 1337 "RTP Control Protocol Extended Reports (RTCP XR)", 1338 RFC 3611, DOI 10.17487/RFC3611, November 2003, 1339 . 1341 [RFC4566] Handley, M., Jacobson, V., and C. Perkins, "SDP: Session 1342 Description Protocol", RFC 4566, DOI 10.17487/RFC4566, 1343 July 2006, . 1345 [RFC5474] Duffield, N., Ed., Chiou, D., Claise, B., Greenberg, A., 1346 Grossglauser, M., and J. Rexford, "A Framework for Packet 1347 Selection and Reporting", RFC 5474, DOI 10.17487/RFC5474, 1348 March 2009, . 1350 [RFC5475] Zseby, T., Molina, M., Duffield, N., Niccolini, S., and F. 1351 Raspall, "Sampling and Filtering Techniques for IP Packet 1352 Selection", RFC 5475, DOI 10.17487/RFC5475, March 2009, 1353 . 1355 [RFC5477] Dietz, T., Claise, B., Aitken, P., Dressler, F., and G. 1356 Carle, "Information Model for Packet Sampling Exports", 1357 RFC 5477, DOI 10.17487/RFC5477, March 2009, 1358 . 1360 [RFC5481] Morton, A. and B. Claise, "Packet Delay Variation 1361 Applicability Statement", RFC 5481, DOI 10.17487/RFC5481, 1362 March 2009, . 1364 [RFC5905] Mills, D., Martin, J., Ed., Burbank, J., and W. Kasch, 1365 "Network Time Protocol Version 4: Protocol and Algorithms 1366 Specification", RFC 5905, DOI 10.17487/RFC5905, June 2010, 1367 . 1369 [RFC6035] Pendleton, A., Clark, A., Johnston, A., and H. Sinnreich, 1370 "Session Initiation Protocol Event Package for Voice 1371 Quality Reporting", RFC 6035, DOI 10.17487/RFC6035, 1372 November 2010, . 1374 [RFC6776] Clark, A. and Q. Wu, "Measurement Identity and Information 1375 Reporting Using a Source Description (SDES) Item and an 1376 RTCP Extended Report (XR) Block", RFC 6776, 1377 DOI 10.17487/RFC6776, October 2012, 1378 . 1380 [RFC6792] Wu, Q., Ed., Hunt, G., and P. Arden, "Guidelines for Use 1381 of the RTP Monitoring Framework", RFC 6792, 1382 DOI 10.17487/RFC6792, November 2012, 1383 . 1385 [RFC7003] Clark, A., Huang, R., and Q. Wu, Ed., "RTP Control 1386 Protocol (RTCP) Extended Report (XR) Block for Burst/Gap 1387 Discard Metric Reporting", RFC 7003, DOI 10.17487/RFC7003, 1388 September 2013, . 1390 [RFC7012] Claise, B., Ed. and B. Trammell, Ed., "Information Model 1391 for IP Flow Information Export (IPFIX)", RFC 7012, 1392 DOI 10.17487/RFC7012, September 2013, 1393 . 1395 [RFC7014] D'Antonio, S., Zseby, T., Henke, C., and L. Peluso, "Flow 1396 Selection Techniques", RFC 7014, DOI 10.17487/RFC7014, 1397 September 2013, . 1399 [RFC7594] Eardley, P., Morton, A., Bagnulo, M., Burbridge, T., 1400 Aitken, P., and A. Akhter, "A Framework for Large-Scale 1401 Measurement of Broadband Performance (LMAP)", RFC 7594, 1402 DOI 10.17487/RFC7594, September 2015, 1403 . 1405 [RFC7799] Morton, A., "Active and Passive Metrics and Methods (with 1406 Hybrid Types In-Between)", RFC 7799, DOI 10.17487/RFC7799, 1407 May 2016, . 1409 [I-D.ietf-ippm-initial-registry] 1410 Morton, A., Bagnulo, M., Eardley, P., and K. D'Souza, 1411 "Initial Performance Metric Registry Entries", draft-ietf- 1412 ippm-initial-registry-01 (work in progress), July 2016. 1414 [RFC6991] Schoenwaelder, J., Ed., "Common YANG Data Types", 1415 RFC 6991, DOI 10.17487/RFC6991, July 2013, 1416 . 1418 Authors' Addresses 1420 Marcelo Bagnulo 1421 Universidad Carlos III de Madrid 1422 Av. Universidad 30 1423 Leganes, Madrid 28911 1424 SPAIN 1426 Phone: 34 91 6249500 1427 Email: marcelo@it.uc3m.es 1428 URI: http://www.it.uc3m.es 1430 Benoit Claise 1431 Cisco Systems, Inc. 1432 De Kleetlaan 6a b1 1433 1831 Diegem 1434 Belgium 1436 Email: bclaise@cisco.com 1438 Philip Eardley 1439 BT 1440 Adastral Park, Martlesham Heath 1441 Ipswich 1442 ENGLAND 1444 Email: philip.eardley@bt.com 1445 Al Morton 1446 AT&T Labs 1447 200 Laurel Avenue South 1448 Middletown, NJ 1449 USA 1451 Email: acmorton@att.com 1453 Aamer Akhter 1454 Consultant 1455 118 Timber Hitch 1456 Cary, NC 1457 USA 1459 Email: aakhter@gmail.com