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Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Working Group A. Choudhary 3 Internet-Draft Cisco Systems 4 Intended status: Standards Track I. Chen 5 Expires: September 7, 2022 The MITRE Corporation 6 March 06, 2022 8 YANG Model for QoS Operational Parameters 9 draft-asechoud-rtgwg-qos-oper-model-10 11 Abstract 13 This document describes a YANG model for Quality of Service (QoS) 14 operational parameters. 16 Status of This Memo 18 This Internet-Draft is submitted in full conformance with the 19 provisions of BCP 78 and BCP 79. 21 Internet-Drafts are working documents of the Internet Engineering 22 Task Force (IETF). Note that other groups may also distribute 23 working documents as Internet-Drafts. The list of current Internet- 24 Drafts is at https://datatracker.ietf.org/drafts/current/. 26 Internet-Drafts are draft documents valid for a maximum of six months 27 and may be updated, replaced, or obsoleted by other documents at any 28 time. It is inappropriate to use Internet-Drafts as reference 29 material or to cite them other than as "work in progress." 31 This Internet-Draft will expire on September 7, 2022. 33 Copyright Notice 35 Copyright (c) 2022 IETF Trust and the persons identified as the 36 document authors. All rights reserved. 38 This document is subject to BCP 78 and the IETF Trust's Legal 39 Provisions Relating to IETF Documents 40 (https://trustee.ietf.org/license-info) in effect on the date of 41 publication of this document. Please review these documents 42 carefully, as they describe your rights and restrictions with respect 43 to this document. Code Components extracted from this document must 44 include Simplified BSD License text as described in Section 4.e of 45 the Trust Legal Provisions and are provided without warranty as 46 described in the Simplified BSD License. 48 Table of Contents 50 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 51 1.1. Tree Diagrams . . . . . . . . . . . . . . . . . . . . . . 2 52 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 2 53 3. QoS Operational Model Design . . . . . . . . . . . . . . . . 3 54 4. Modules Tree Structure . . . . . . . . . . . . . . . . . . . 4 55 5. Modules . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 56 5.1. ietf-qos-oper . . . . . . . . . . . . . . . . . . . . . . 6 57 6. Security Considerations . . . . . . . . . . . . . . . . . . . 14 58 7. Acknowledgement . . . . . . . . . . . . . . . . . . . . . . . 14 59 8. References . . . . . . . . . . . . . . . . . . . . . . . . . 15 60 8.1. Normative References . . . . . . . . . . . . . . . . . . 15 61 8.2. Informative References . . . . . . . . . . . . . . . . . 16 62 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 16 64 1. Introduction 66 This document defines a base YANG [RFC6020] [RFC7950] data module for 67 Quality of Service (QoS) operational parameters. Remote Procedure 68 Calls (RPC) or notification definition is currently not part of this 69 document and will be added later if necessary. QoS configuration 70 modules are defined by [I-D.ietf-rtgwg-qos-model]. 72 Editorial Note: (To be removed by RFC Editor) 74 This draft contains several placeholder values that need to be 75 replaced with finalized values at the time of publication. Please 76 apply the following replacements: o "XXXX" --> the assigned RFC value 77 for this draft both in this draft and in the YANG models under the 78 revision statement. o The "revision" date in model, in the format 79 XXXX-XX-XX, needs to be updated with the date the draft gets 80 approved. 82 The YANG modules in this document conform to the Network Management 83 Datastore Architecture (NMDA) [RFC8342]. 85 1.1. Tree Diagrams 87 Tree diagrams used in this document follow the notation defined in 88 [RFC8340] 90 2. Terminology 92 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 93 "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and 94 "OPTIONAL" in this document are to be interpreted as described in BCP 95 14 [RFC2119] [RFC8174] when, and only when, they appear in all 96 capitals, as shown here. 98 3. QoS Operational Model Design 100 QoS operational model include QoS policy applied to an interface in 101 each direction of traffic. For each QoS policy applied to an 102 interface the model further includes counters for associated 103 Classifiers, Meters and Queues in a particular direction. To 104 modularize and for reusability, grouping have been defined for 105 various counters of classifier, Meters and Queues. The target is 106 assumed to be interface but the groupings can be used for any other 107 target type where QoS policy is applied. 109 [I-D.ietf-rtgwg-qos-model] defines various building blocks for 110 applying a QoS Policy on a target. It includes QoS Policy 111 configuration, which is a container of various classifiers and 112 corresponding actions which are configured for traffic conditioning. 113 This drafts defines the various counters for these building blocks. 114 ietf-qos-oper module defined in this draft augments ietf-interfaces 115 [RFC8343] module. 117 Classifier statistics contains counters for packets and bytes matched 118 to the traffic in a direction and also average rate at which traffic 119 is hitting a classifier. Classification criterion may be based on 120 IP, MPLS or Ethernet. Counters defined in this draft are agnostic to 121 underlying data plane technology. 123 Statistics of meter is modeled based on commonly used algorithms in 124 industry, Single Rate Tri Color Marking (srTCM) [RFC2697] meter, Two 125 Rate Tri Color Marking (trTCM) [RFC2698] meter. Metering statistics 126 includes counters corresponding to various rates configured. A 127 metering container is referred by a metering identifier. This 128 identifier could be a classifier name if the metering configuration 129 is inline with classifier or it could be metering template name if 130 the metering is configured as separate entity and associated with the 131 classifier. 133 Queuing statistics includes counters corresponding to various queues 134 associated with the policy. A queuing container is referred by 135 queuing identifier. This identifier could be a classifier name if 136 the queuing configuration is inline with classifier and hence there 137 is one-to-one mapping between a classifier and a queue or it could be 138 a separate queue identifier if one or more than one classifiers are 139 associated with a queue. 141 4. Modules Tree Structure 143 This document defines counters for classifiers, meters and queues. 145 Classifier statistics consists of list of classifier entries 146 identified by a classifier entry name. Classifier counters include 147 matched packets, bytes and average rate of traffic matching a 148 particular classifier. 150 Metering statistics consists of meters identified by an identifier. 151 Metering counters include conform, exceed, violate and drop packets 152 and bytes. 154 Queuing counters include instantaneous, peak, average queue length, 155 as well as output conform, exceed, tail drop packets and bytes. 157 Named statistics is defined as statistics which are tagged by a name. 158 This could be aggregated or non-aggregated. Aggregated named 159 statistics is defined as counters which are aggregated across 160 classifier entries in a policy applied to an interface in a 161 particular direction. Non-aggregated named statistics are counters 162 of classifier, metering or queuing which have the same tag name but 163 maintained separately. 165 module: ietf-qos-oper 166 augment /if:interfaces/if:interface: 167 +--ro qos-interface-statistics 168 +--ro stats-per-direction* [] 169 +--ro direction? identityref 170 +--ro policy-name? string 171 +--ro classifier-statistics* [] 172 | +--ro classifier-entry-name? string 173 | +--ro classified-pkts? uint64 174 | +--ro classified-bytes? uint64 175 | +--ro classified-rate? uint64 176 +--ro named-statistics* [] 177 | +--ro stats-name? string 178 | +--ro aggregated 179 | | +--ro pkts? uint64 180 | | +--ro bytes? uint64 181 | | +--ro rate? uint64 182 | +--ro non-aggregated 183 | +--ro classifier-statistics* [] 184 | | +--ro classifier-entry-name? string 185 | | +--ro classified-pkts? uint64 186 | | +--ro classified-bytes? uint64 187 | | +--ro classified-rate? uint64 188 | +--ro metering-statistics* [] 189 | | +--ro meter-id? string 190 | | +--ro conform-pkts? uint64 191 | | +--ro conform-bytes? uint64 192 | | +--ro conform-rate? uint64 193 | | +--ro exceed-pkts? uint64 194 | | +--ro exceed-bytes? uint64 195 | | +--ro exceed-rate? uint64 196 | | +--ro violate-pkts? uint64 197 | | +--ro violate-bytes? uint64 198 | | +--ro violate-rate? uint64 199 | | +--ro meter-drop-pkts? uint64 200 | | +--ro meter-drop-bytes? uint64 201 | +--ro queueing-statistics* [] 202 | +--ro queue-id? string 203 | +--ro output-conform-pkts? uint64 204 | +--ro output-conform-bytes? uint64 205 | +--ro output-exceed-pkts? uint64 206 | +--ro output-exceed-bytes? uint64 207 | +--ro queue-current-size-bytes? uint64 208 | +--ro queue-average-size-bytes? uint64 209 | +--ro queue-peak-size-bytes? uint64 210 | +--ro tailed-drop-pkts? uint64 211 | +--ro tailed-drop-bytes? uint64 212 | +--ro red-drop-pkts? uint64 213 | +--ro red-drop-bytes? uint64 214 | +--ro red-ecn-marked-pkts? uint64 215 | +--ro red-ecn-marked-bytes? uint64 216 | +--ro wred-stats* [] 217 | +--ro profile-id? uint64 218 | +--ro red-drop-pkts? uint64 219 | +--ro red-drop-bytes? uint64 220 | +--ro red-ecn-marked-pkts? uint64 221 | +--ro red-ecn-marked-bytes? uint64 222 +--ro metering-statistics* [] 223 | +--ro meter-id? string 224 | +--ro conform-pkts? uint64 225 | +--ro conform-bytes? uint64 226 | +--ro conform-rate? uint64 227 | +--ro exceed-pkts? uint64 228 | +--ro exceed-bytes? uint64 229 | +--ro exceed-rate? uint64 230 | +--ro violate-pkts? uint64 231 | +--ro violate-bytes? uint64 232 | +--ro violate-rate? uint64 233 | +--ro meter-drop-pkts? uint64 234 | +--ro meter-drop-bytes? uint64 235 +--ro queueing-statistics* [] 236 +--ro queue-id? string 237 +--ro output-conform-pkts? uint64 238 +--ro output-conform-bytes? uint64 239 +--ro output-exceed-pkts? uint64 240 +--ro output-exceed-bytes? uint64 241 +--ro queue-current-size-bytes? uint64 242 +--ro queue-average-size-bytes? uint64 243 +--ro queue-peak-size-bytes? uint64 244 +--ro tailed-drop-pkts? uint64 245 +--ro tailed-drop-bytes? uint64 246 +--ro red-drop-pkts? uint64 247 +--ro red-drop-bytes? uint64 248 +--ro red-ecn-marked-pkts? uint64 249 +--ro red-ecn-marked-bytes? uint64 250 +--ro wred-stats* [] 251 +--ro profile-id? uint64 252 +--ro red-drop-pkts? uint64 253 +--ro red-drop-bytes? uint64 254 +--ro red-ecn-marked-pkts? uint64 255 +--ro red-ecn-marked-bytes? uint64 257 5. Modules 259 5.1. ietf-qos-oper 261 file "ietf-qos-oper.yang" 263 module ietf-qos-oper { 264 yang-version 1.1; 265 namespace "urn:ietf:params:xml:ns:yang:ietf-qos-oper"; 266 prefix oper; 267 import ietf-interfaces { 268 prefix if; 269 reference 270 "RFC8343: A YANG Data Model for Interface Management"; 271 } 272 organization "IETF RTG (Routing Area) Working Group"; 273 contact 274 "WG Web: 275 WG List: 276 Editor: Aseem Choudhary 277 "; 278 description 279 "This module contains a collection of YANG definitions for 280 qos operational specification. 281 Copyright (c) 2019 IETF Trust and the persons identified as 282 authors of the code. All rights reserved. 284 Redistribution and use in source and binary forms, with or 285 without modification, is permitted pursuant to, and subject 286 to the license terms contained in, the Simplified BSD License 287 set forth in Section 4.c of the IETF Trust's Legal Provisions 288 Relating to IETF Documents 289 (http://trustee.ietf.org/license-info). 290 This version of this YANG module is part of RFC XXXX; see 291 the RFC itself for full legal notices."; 292 revision 2022-03-06 { 293 description 294 "Latest revision for qos operational statistics"; 295 reference 296 "RFC XXXX: YANG Model for QOS Operational Parameters"; 297 } 298 identity direction { 299 description 300 "This is identity of traffic direction"; 301 } 302 identity inbound { 303 base direction; 304 description 305 "Direction of traffic coming into the network entry"; 306 } 307 identity outbound { 308 base direction; 309 description 310 "Direction of traffic going out of the network entry"; 311 } 312 grouping classifier-entry-stats { 313 description 314 " 315 This group defines the classifier filter counters of 316 each classifier entry 317 "; 318 leaf classified-pkts { 319 type uint64; 320 description 321 " Number of total packets which filtered 322 to a classifier-entry"; 323 } 324 leaf classified-bytes { 325 type uint64; 326 description 327 " Number of total bytes which filtered 328 to a classifier-entry"; 329 } 330 leaf classified-rate { 331 type uint64; 332 units "bits-per-second"; 333 description 334 " Rate of average data flow through a 335 classifier-entry"; 336 } 337 } 338 grouping named-stats { 339 description 340 "QoS matching statistics associated with a stats-name"; 341 leaf pkts { 342 type uint64; 343 description 344 " Number of total matched packets associated 345 to a statistics name"; 346 } 347 leaf bytes { 348 type uint64; 349 description 350 " Number of total matched bytes associated 351 to a statistics name"; 352 } 353 leaf rate { 354 type uint64; 355 units "bits-per-second"; 356 description 357 " Rate of average matched data which is associated 358 to a statistics name"; 359 } 360 } 361 grouping queue-stats { 362 description 363 "Queuing Counters"; 364 leaf output-conform-pkts { 365 type uint64; 366 description 367 "Number of packets transmitted from queue "; 368 } 369 leaf output-conform-bytes { 370 type uint64; 371 description 372 "Number of bytes transmitted from queue "; 373 } 374 leaf output-exceed-pkts { 375 type uint64; 376 description 377 "Number of packets transmitted from queue "; 378 } 379 leaf output-exceed-bytes { 380 type uint64; 381 description 382 "Number of bytes transmitted from queue "; 383 } 384 leaf queue-current-size-bytes { 385 type uint64; 386 description 387 "Number of bytes currently buffered "; 388 } 389 leaf queue-average-size-bytes { 390 type uint64; 391 description 392 "Average queue size in number of bytes"; 393 } 394 leaf queue-peak-size-bytes { 395 type uint64; 396 description 397 "Peak buffer queue size in bytes "; 398 } 399 leaf tailed-drop-pkts { 400 type uint64; 401 description 402 "Total number of packets tail-dropped "; 403 } 404 leaf tailed-drop-bytes { 405 type uint64; 406 description 407 "Total number of bytes tail-dropped "; 408 } 409 leaf red-drop-pkts { 410 type uint64; 411 description 412 "Total number of packets dropped through RED mechanism"; 413 } 414 leaf red-drop-bytes { 415 type uint64; 416 description 417 "Total number of bytes dropped through RED mechanism"; 418 } 419 leaf red-ecn-marked-pkts { 420 type uint64; 421 description 422 "Total number of packets ECN marked through RED mechanism"; 423 } 424 leaf red-ecn-marked-bytes { 425 type uint64; 426 description 427 "Total number of bytes ECN marked through RED mechanism"; 429 } 430 } 431 grouping meter-stats { 432 description 433 "Metering counters"; 434 leaf conform-pkts { 435 type uint64; 436 description 437 "Number of conform packets"; 438 } 439 leaf conform-bytes { 440 type uint64; 441 description 442 "Bytes of conform packets"; 443 } 444 leaf conform-rate { 445 type uint64; 446 units "bits-per-second"; 447 description 448 "Traffic Rate measured as conformimg"; 449 } 450 leaf exceed-pkts { 451 type uint64; 452 description 453 "Number of packets counted as exceeding"; 454 } 455 leaf exceed-bytes { 456 type uint64; 457 description 458 "Bytes of packets counted as exceeding"; 459 } 460 leaf exceed-rate { 461 type uint64; 462 units "bits-per-second"; 463 description 464 "Traffic Rate measured as exceeding"; 465 } 466 leaf violate-pkts { 467 type uint64; 468 description 469 "Number of packets counted as violating"; 470 } 471 leaf violate-bytes { 472 type uint64; 473 description 474 "Bytes of packets counted as violating"; 475 } 476 leaf violate-rate { 477 type uint64; 478 units "bits-per-second"; 479 description 480 "Traffic Rate measured as violating"; 481 } 482 leaf meter-drop-pkts { 483 type uint64; 484 description 485 "Number of packets dropped by meter"; 486 } 487 leaf meter-drop-bytes { 488 type uint64; 489 description 490 "Bytes of packets dropped by meter"; 491 } 492 } 493 grouping classifier-entry-statistics { 494 description 495 "Statistics for a classifier entry"; 496 leaf classifier-entry-name { 497 type string; 498 description 499 "Classifier Entry Name"; 500 } 501 uses classifier-entry-stats; 502 } 504 grouping queuing-stats { 505 description 506 "Statistics for a queue"; 507 leaf queue-id { 508 type string; 509 description 510 "Queue Identifier"; 511 } 512 uses queue-stats; 513 list wred-stats { 514 config false; 515 description 516 "Qos RED statistics for each color of traffic"; 517 leaf profile-id { 518 type uint64; 519 description 520 "profile-id for each color of traffic"; 521 } 522 leaf red-drop-pkts { 523 type uint64; 524 description 525 "Total number of packets dropped through RED mechanism"; 526 } 527 leaf red-drop-bytes { 528 type uint64; 529 description 530 "Total number of bytes dropped through RED mechanism"; 531 } 532 leaf red-ecn-marked-pkts { 533 type uint64; 534 description 535 "Total number of packets ECN marked through RED mechanism"; 536 } 537 leaf red-ecn-marked-bytes { 538 type uint64; 539 description 540 "Total number of bytes ECN marked through RED mechanism"; 541 } 542 } 543 } 545 grouping metering-stats { 546 description 547 "Statistics for a meter"; 548 leaf meter-id { 549 type string; 550 description 551 "Meter Identifier"; 552 } 553 uses meter-stats; 554 } 556 augment "/if:interfaces/if:interface" { 557 description 558 "Augments Qos Target Entry to Interface module"; 560 container qos-interface-statistics { 561 config false; 562 description 563 "Qos Interface statistics"; 565 list stats-per-direction { 566 description 567 "Qos Interface statistics for ingress or egress direction"; 569 leaf direction { 570 type identityref { 571 base direction; 572 } 573 description 574 "Direction of the traffic flow either inbound 575 or outbound"; 576 } 577 leaf policy-name { 578 type string; 579 description 580 "Policy entry name for single level policy as well as 581 for Hierarchical policies. For Hierarchical policies, 582 this represent relative path as well as the last level 583 policy name."; 584 } 586 list classifier-statistics { 587 description 588 "Classifier Statistics for each Classifier Entry in a 589 Policy applied in a particular direction"; 590 reference 591 "RFC3289: Section 6"; 592 uses classifier-entry-statistics; 593 } 594 list named-statistics { 595 config false; 596 description 597 "Statistics for a statistics-name"; 598 leaf stats-name { 599 type string; 600 description 601 "Statistics name"; 602 } 603 container aggregated { 604 description 605 "Matched aggregated statistics for a statistics-name"; 606 uses named-stats; 607 } 608 container non-aggregated { 609 description 610 "Statistics for non-aggregated statistics-name"; 611 list classifier-statistics { 612 description 613 "Classifier Statistics for each Classifier Entry in a 614 Policy applied in a particular direction"; 615 uses classifier-entry-statistics; 616 } 617 list metering-statistics { 618 config false; 619 description 620 "Statistics for each Meter associated with 621 the Policy"; 622 reference 623 "RFC2697: A Single Rate Three Color Marker 624 RFC2698: A Two Rate Three Color Marker"; 625 uses metering-stats; 626 } 627 list queueing-statistics { 628 config false; 629 description 630 "Statistics for each Queue associated with 631 the Policy"; 632 uses queuing-stats; 633 } 634 } 635 } 636 list metering-statistics { 637 config false; 638 description 639 "Statistics for each Meter associated with the Policy"; 640 reference 641 "RFC2697: A Single Rate Three Color Marker 642 RFC2698: A Two Rate Three Color Marker"; 643 uses metering-stats; 644 } 645 list queueing-statistics { 646 config false; 647 description 648 "Statistics for each Queue associated with the Policy"; 649 uses queuing-stats; 650 } 651 } 652 } 653 } 654 } 656 658 6. Security Considerations 660 7. Acknowledgement 662 MITRE has approved this document for Public Release, Distribution 663 Unlimited, with Public Release Case Number 20-0518. The author's 664 affiliation with The MITRE Corporation is provided for identification 665 purposes only, and is not intended to convey or imply MITRE's 666 concurrence with, or support for, the positions, opinions or 667 viewpoints expressed by the author. 669 8. References 671 8.1. Normative References 673 [I-D.ietf-rtgwg-qos-model] 674 Choudhary, A., Jethanandani, M., Aries, E., and I. Chen, 675 "YANG Models for Quality of Service (QoS)", draft-ietf- 676 rtgwg-qos-model-07 (work in progress), March 2022. 678 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 679 Requirement Levels", BCP 14, RFC 2119, 680 DOI 10.17487/RFC2119, March 1997, 681 . 683 [RFC2697] Heinanen, J. and R. Guerin, "A Single Rate Three Color 684 Marker", RFC 2697, DOI 10.17487/RFC2697, September 1999, 685 . 687 [RFC2698] Heinanen, J. and R. Guerin, "A Two Rate Three Color 688 Marker", RFC 2698, DOI 10.17487/RFC2698, September 1999, 689 . 691 [RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for 692 the Network Configuration Protocol (NETCONF)", RFC 6020, 693 DOI 10.17487/RFC6020, October 2010, 694 . 696 [RFC7950] Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language", 697 RFC 7950, DOI 10.17487/RFC7950, August 2016, 698 . 700 [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 701 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, 702 May 2017, . 704 [RFC8342] Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K., 705 and R. Wilton, "Network Management Datastore Architecture 706 (NMDA)", RFC 8342, DOI 10.17487/RFC8342, March 2018, 707 . 709 [RFC8343] Bjorklund, M., "A YANG Data Model for Interface 710 Management", RFC 8343, DOI 10.17487/RFC8343, March 2018, 711 . 713 8.2. Informative References 715 [RFC8340] Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams", 716 BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018, 717 . 719 Authors' Addresses 721 Aseem Choudhary 722 Cisco Systems 723 170 W. Tasman Drive 724 San Jose, CA 95134 725 US 727 Email: asechoud@cisco.com 729 Ing-Wher Chen 730 The MITRE Corporation 732 Email: ingwherchen@mitre.org