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Checking references for intended status: Proposed Standard ---------------------------------------------------------------------------- (See RFCs 3967 and 4897 for information about using normative references to lower-maturity documents in RFCs) == Outdated reference: A later version (-01) exists of draft-ietf-teas-ietf-network-slice-nbi-yang-00 == Outdated reference: A later version (-10) exists of draft-ietf-teas-te-service-mapping-yang-09 == Outdated reference: A later version (-16) exists of draft-ietf-opsawg-l2nm-12 == Outdated reference: A later version (-10) exists of draft-ietf-teas-ietf-network-slices-05 == Outdated reference: A later version (-10) exists of draft-bestbar-teas-ns-packet-08 Summary: 1 error (**), 0 flaws (~~), 7 warnings (==), 1 comment (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 TEAS Working Group D. Dhody 3 Internet-Draft B. Wu 4 Intended status: Standards Track Huawei Technologies 5 Expires: 4 September 2022 3 March 2022 7 IETF Network Slice Service Mapping YANG Model 8 draft-dhody-teas-ietf-network-slice-mapping-00 10 Abstract 12 This document provides a YANG data model to map IETF network slice 13 service to Traffic Engineering (TE) models (e.g., the Virtual Network 14 (VN) model or the TE Tunnel etc). It also supports mapping to the 15 VPN Network models and Network Resource Partition (NRP) models. 16 These models are referred to as IETF network slice service mapping 17 model and are applicable generically for the seamless control and 18 management of the IETF network slice service with underlying TE/VPN 19 support. 21 The models are principally used for monitoring and diagnostics of the 22 management systems to show how the IETF network slice service 23 requests are mapped onto underlying network resource and TE/VPN 24 models. 26 Status of This Memo 28 This Internet-Draft is submitted in full conformance with the 29 provisions of BCP 78 and BCP 79. 31 Internet-Drafts are working documents of the Internet Engineering 32 Task Force (IETF). Note that other groups may also distribute 33 working documents as Internet-Drafts. The list of current Internet- 34 Drafts is at https://datatracker.ietf.org/drafts/current/. 36 Internet-Drafts are draft documents valid for a maximum of six months 37 and may be updated, replaced, or obsoleted by other documents at any 38 time. It is inappropriate to use Internet-Drafts as reference 39 material or to cite them other than as "work in progress." 41 This Internet-Draft will expire on 4 September 2022. 43 Copyright Notice 45 Copyright (c) 2022 IETF Trust and the persons identified as the 46 document authors. All rights reserved. 48 This document is subject to BCP 78 and the IETF Trust's Legal 49 Provisions Relating to IETF Documents (https://trustee.ietf.org/ 50 license-info) in effect on the date of publication of this document. 51 Please review these documents carefully, as they describe your rights 52 and restrictions with respect to this document. Code Components 53 extracted from this document must include Revised BSD License text as 54 described in Section 4.e of the Trust Legal Provisions and are 55 provided without warranty as described in the Revised BSD License. 57 Table of Contents 59 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 60 2. Conventions . . . . . . . . . . . . . . . . . . . . . . . . . 3 61 2.1. Tree Diagrams . . . . . . . . . . . . . . . . . . . . . . 3 62 2.2. Prefixes in Data Node Names . . . . . . . . . . . . . . . 4 63 2.3. References in the Model . . . . . . . . . . . . . . . . . 4 64 3. Model Design . . . . . . . . . . . . . . . . . . . . . . . . 5 65 3.1. Open Questions . . . . . . . . . . . . . . . . . . . . . 6 66 4. Tree Structure . . . . . . . . . . . . . . . . . . . . . . . 6 67 5. YANG Model . . . . . . . . . . . . . . . . . . . . . . . . . 7 68 6. Security Considerations . . . . . . . . . . . . . . . . . . . 12 69 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12 70 8. References . . . . . . . . . . . . . . . . . . . . . . . . . 13 71 8.1. Normative References . . . . . . . . . . . . . . . . . . 13 72 8.2. Informative References . . . . . . . . . . . . . . . . . 14 73 Appendix A. Acknowledgments . . . . . . . . . . . . . . . . . . 15 74 Appendix B. Examples . . . . . . . . . . . . . . . . . . . . . . 15 75 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 15 77 1. Introduction 79 Data models are a representation of objects that can be configured or 80 monitored within a system. Within the IETF, YANG [RFC7950] is the 81 language of choice for documenting data models, and YANG models have 82 been produced to allow configuration or modeling of a variety of 83 network devices, protocol instances, and network services. 85 The YANG model discussed in this document augments the IETF Network 86 Slice Service YANG model [I-D.ietf-teas-ietf-network-slices], which 87 is used to operate IETF Network Slices during the IETF Network Slice 88 instantiation. This provides a way to map IETF network slice service 89 to Traffic Engineering (TE) models (e.g., the Virtual Network (VN) 90 model or the TE Tunnel etc). Alternatively, it also supports mapping 91 to the VPN Network models and Network Resource Partition (NRP) 92 models. 94 The model supports: 96 * A mapping of the IETF Network Slice with the VPN network models - 97 LxNM. This mapping can be populated at the time of IETF network 98 service realization. This mapping information is internal and 99 used for monitoring and diagnostics purpose such as telemetry, 100 auto-scaling, closed-loop automation. Note that the LxNM may 101 further map to other TE resources as specified in 102 [I-D.ietf-teas-te-service-mapping-yang]. A mapping to the NRP can 103 also be populated. 105 * A mapping of the IETF Network Slice with the underlying TE 106 resources directly. The TE resources could be in a form of VN, 107 set of TE tunnels, TE abstract topology etc. This mapping can be 108 populated by the network at the time of realization of the IETF 109 network slice service. It is also possible to configure the 110 mapping provided one is aware of NRP/VN/tunnels. This mapping 111 mode is used only when the there is an awareness of VN or TE by 112 the consumer of the model. Otherwise this mapping information is 113 internal and used for monitoring and diagnostics purpose such as 114 telemetry, auto-scaling, closed-loop automation. 116 * Possibility to request creation of a new VN/Tunnel to be binded to 117 IETF network slice. 119 * Indication to share the VN/Tunnel sharing (with or without 120 modification) for the IETF network slice. 122 * Support for configuration of underlying TE properties (as opposed 123 to existing VN or tunnels). 125 Note: The RFC Editor will replace XXXX with the number assigned to 126 the RFC once this draft becomes an RFC. 128 2. Conventions 130 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 131 "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and 132 "OPTIONAL" in this document are to be interpreted as described in 133 BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all 134 capitals, as shown here. 136 2.1. Tree Diagrams 138 A simplified graphical representation of the data model is used in 139 this document. The meaning of the symbols in these diagrams is 140 defined in [RFC8340]. 142 2.2. Prefixes in Data Node Names 144 In this document, names of data nodes and other data model objects 145 are often used without a prefix, as long as it is clear from the 146 context in which YANG module each name is defined. Otherwise, names 147 are prefixed using the standard prefix associated with the 148 corresponding YANG module, as shown in Table 1. 150 +========+==========+=============================================+ 151 | Prefix | YANG | Reference | 152 | | module | | 153 +========+==========+=============================================+ 154 | nw | ietf- | [RFC8345] | 155 | | network | | 156 +--------+----------+---------------------------------------------+ 157 | tsmt | ietf-te- | [I-D.ietf-teas-te-service-mapping-yang] | 158 | | service- | | 159 | | mapping- | | 160 | | types | | 161 +--------+----------+---------------------------------------------+ 162 | l3vpn- | ietf- | [RFC9182] | 163 | ntw | l3vpn- | | 164 | | ntw | | 165 +--------+----------+---------------------------------------------+ 166 | l2vpn- | ietf- | [I-D.ietf-opsawg-l2nm] | 167 | ntw | l2vpn- | | 168 | | ntw | | 169 +--------+----------+---------------------------------------------+ 170 | ietf- | ietf- | [I-D.ietf-teas-ietf-network-slice-nbi-yang] | 171 | ns | network- | | 172 | | slice | | 173 +--------+----------+---------------------------------------------+ 174 | nrp | ietf-nrp | [I-D.wd-teas-nrp-yang] | 175 +--------+----------+---------------------------------------------+ 177 Table 1 179 2.3. References in the Model 181 Following additional documents are referenced in the model defined in 182 this document - 183 +==========================+==============================+ 184 | Document | Reference | 185 +==========================+==============================+ 186 | Realizing Network Slices | [I-D.bestbar-teas-ns-packet] | 187 | in IP/MPLS Networks | | 188 +--------------------------+------------------------------+ 190 Table 2 192 3. Model Design 194 The YANG model specified in this document augments the IETF network 195 slice service YANG model [I-D.ietf-teas-ietf-network-slice-nbi-yang]. 197 Currently following mapping are supported: 199 * L3NM: The L3 network model (L3NM) describes a L3VPN Service in the 200 Service Provider Network. It contains information of the Service 201 Provider network and might include allocated resources. It can be 202 used by network controllers to manage and control the L3VPN 203 Service configuration in the Service Provider network. This model 204 maps an IETF network slice to a L3VPN ID. 206 * L2NM: The L2 network model (L2NM) describes a L2VPN Service in the 207 Service Provider Network. It contains information of the Service 208 Provider network and might include allocated resources. It can be 209 used by network controllers to manage and control the L2VPN 210 Service configuration in the Service Provider network. This model 211 maps an IETF network slice to a L2VPN ID. 213 * TE: The TE mapping is specified in 214 [I-D.ietf-teas-te-service-mapping-yang]. The mapping can be done 215 to the following TE resouces: 217 - Virtual Networks (VN) [RFC8453] 219 - TE-Tunnels 221 - TE-Topology 223 * NRP: [I-D.ietf-teas-ietf-network-slices] defines IETF network 224 slice services that provide connectivity coupled with network 225 resources commitment between a number of endpoints over a shared 226 network infrastructure and, for scalability concerns, defines NRP 227 to host one or a group of network slice services according to 228 characteristics including SLOs and SLEs. Along with mapping to 229 VPN, this model maps an IETF network slice to a NRP ID. 231 3.1. Open Questions 233 The following open questions needs to be addressed in a future 234 revision: 236 * Is there a need/use-case to map IETF Network slice Connection 237 Group and/or Connectivity Construct as well? 239 * Is there a need/use-case to map IETF Network slice to NRP 240 directly? 242 * Is there a need/use-case to map IETF Network slice Endpoints? 244 * Is there a need to indicate "map-type" (new, share) for NRP and 245 VPNs? 247 4. Tree Structure 248 module: ietf-network-slice-mapping 250 augment /ietf-ns:network-slices/ietf-ns:network-slice: 251 +--rw mapping! 252 +--rw ns-mapping 253 +--rw map-to? identityref 254 +--rw (map)? 255 +--:(l3vpn) 256 | +--rw l3vpn-id? leafref 257 | +--rw l3vpn-nrp-id? 258 | -> /nw:networks/network/nrp:nrp/nrp-id 259 +--:(l2vpn) 260 | +--rw l2vpn-id? leafref 261 | +--rw l2vpn-nrp-id? 262 | -> /nw:networks/network/nrp:nrp/nrp-id 263 +--:(te) 264 +--rw te-mapping 265 +--rw map-type? identityref 266 +--rw te-policy 267 | +--rw color? uint32 268 | +--rw protection-type? identityref 269 | +--rw availability-type? identityref 270 +--rw (te)? 271 | +--:(vn) 272 | | +--rw vn* 273 | | -> /vn:virtual-network/vn/vn-id 274 | +--:(te-topo) 275 | | +--rw vn-topology-id? 276 | | | te-types:te-topology-id 277 | | +--rw abstract-node? 278 | | -> /nw:networks/network/node/node-id 279 | +--:(te-tunnel) 280 | +--rw te-tunnel* te:tunnel-ref 281 | +--rw sr-policy* 282 | [policy-color-ref policy-endpoint-ref] 283 | {sr-policy}? 284 | +--rw policy-color-ref leafref 285 | +--rw policy-endpoint-ref leafref 286 +--rw te-mapping-template-ref? leafref 287 {template}? 289 5. YANG Model 290 file "ietf-network-slice-mapping@2022-03-03.yang" 291 module ietf-network-slice-mapping { 292 yang-version 1.1; 293 namespace 294 "urn:ietf:params:xml:ns:yang:ietf-network-slice-mapping"; 295 prefix ietf-nsm; 297 import ietf-network { 298 prefix nw; 299 reference 300 "RFC 8345: A YANG Data Model for Network Topologies"; 301 } 302 import ietf-network-slice { 303 prefix ietf-ns; 304 reference 305 "I-D.ietf-teas-ietf-network-slice-nbi-yang: IETF Network Slice 306 Service YANG Model"; 307 } 308 import ietf-te-service-mapping-types { 309 prefix tsmt; 310 reference 311 "I-D.ietf-teas-te-service-mapping-yang: Traffic Engineering 312 (TE) and Service Mapping YANG Model"; 313 } 314 import ietf-l3vpn-ntw { 315 prefix l3vpn-ntw; 316 reference 317 "RFC9182: A YANG Network Data Model for Layer 3 VPNs"; 318 } 319 import ietf-l2vpn-ntw { 320 prefix l2vpn-ntw; 321 reference 322 "I-D.ietf-opsawg-l2nm: A Layer 2 VPN Network YANG Model"; 323 } 324 import ietf-nrp { 325 prefix nrp; 326 reference 327 "I-D.wd-teas-nrp-yang: A YANG Data Model for Network 328 Resource Partition (NRP)"; 329 } 331 organization 332 "IETF Traffic Engineering Architecture and Signaling (TEAS) 333 Working Group"; 334 contact 335 "WG Web: 336 WG List: 337 Editor: Dhruv Dhody 338 Bo Wu "; 339 description 340 "This module contains a YANG module to map the IETF Network 341 Slice with Traffic Engineering (TE) or VPN Network models. 343 Copyright (c) 2022 IETF Trust and the persons identified as 344 authors of the code. All rights reserved. 346 Redistribution and use in source and binary forms, with or 347 without modification, is permitted pursuant to, and subject to 348 the license terms contained in, the Revised BSD License set 349 forth in Section 4.c of the IETF Trust's Legal Provisions 350 Relating to IETF Documents 351 (https://trustee.ietf.org/license-info). 353 This version of this YANG module is part of RFC XXXX; see the 354 RFC itself for full legal notices."; 356 revision 2022-03-03 { 357 description 358 "initial version."; 359 reference 360 "RFC XXXX: IETF Network Slice Service Mapping YANG Model"; 361 } 363 identity map-to { 364 description 365 "Base identity from which specific map-to are derived."; 366 } 368 identity map-to-vpn { 369 base map-to; 370 description 371 "Map to VPN"; 372 } 374 identity map-to-l3vpn { 375 base map-to-vpn; 376 description 377 "Map to L3VPN"; 378 } 380 identity map-to-l2vpn { 381 base map-to-vpn; 382 description 383 "Map to L2VPN"; 384 } 385 identity map-to-l1vpn { 386 base map-to-vpn; 387 description 388 "Map to L1VPN"; 389 } 391 identity map-to-te { 392 base map-to; 393 description 394 "Map to TE directly"; 395 } 397 identity map-to-nrp { 398 base map-to; 399 description 400 "Map to NRP"; 401 } 403 grouping ns-mapping { 404 description 405 "Mapping between IETF network slice and Network 406 Resource Partition (NRP)/VPN/TE"; 407 container ns-mapping { 408 description 409 "The container for the mapping"; 410 leaf map-to { 411 type identityref { 412 base map-to; 413 } 414 description 415 "Mapping to NRP/VPN/TE"; 416 } 417 choice map { 418 description 419 "Mapping to NRP/VPN/TE"; 420 case l3vpn { 421 leaf l3vpn-id { 422 type leafref { 423 path "/l3vpn-ntw:l3vpn-ntw" 424 + "/l3vpn-ntw:vpn-services" 425 + "/l3vpn-ntw:vpn-service" 426 + "/l3vpn-ntw:vpn-id"; 427 } 428 description 429 "A reference to VPN ID"; 430 } 431 leaf l3vpn-nrp-id { 432 type leafref { 433 path "/nw:networks/nw:network" 434 + "/nrp:nrp/nrp:nrp-id"; 435 } 436 description 437 "A reference to NRP ID"; 438 reference 439 "I-D.bestbar-teas-ns-packet: Realizing 440 Network Slices in IP/MPLS Networks"; 441 } 442 description 443 "Mapping to L3NM"; 444 reference 445 "RFC9182: A YANG Network Data Model for 446 Layer 3 VPNs"; 447 } 448 case l2vpn { 449 leaf l2vpn-id { 450 type leafref { 451 path "/l2vpn-ntw:l2vpn-ntw" 452 + "/l2vpn-ntw:vpn-services" 453 + "/l2vpn-ntw:vpn-service" 454 + "/l2vpn-ntw:vpn-id"; 455 } 456 description 457 "A reference to VPN ID"; 458 } 459 leaf l2vpn-nrp-id { 460 type leafref { 461 path "/nw:networks/nw:network" 462 + "/nrp:nrp/nrp:nrp-id"; 463 } 464 description 465 "A reference to NRP ID"; 466 reference 467 "I-D.bestbar-teas-ns-packet: Realizing 468 Network Slices in IP/MPLS Networks"; 469 } 470 description 471 "Mapping to L2NM"; 472 reference 473 "I-D.ietf-opsawg-l2nm: A Layer 2 VPN 474 Network YANG Model"; 475 } 476 case te { 477 uses tsmt:te-mapping; 478 description 479 "Mapping to TE directly"; 480 reference 481 "I-D.ietf-teas-te-service-mapping-yang: 482 Traffic Engineering (TE) and Service 483 Mapping YANG Model"; 484 } 485 } 486 } 487 } 489 augment "/ietf-ns:network-slices/ietf-ns:network-slice" { 490 description 491 "IETF Network Slice augmented to include the mapping 492 information to the network slice realization"; 493 container mapping { 494 presence "Indicates Mapping information"; 495 description 496 "Container to augment IETF network slice to 497 include NRP / VPN / TE mappings"; 498 uses ns-mapping; 499 } 500 } 501 } 503 505 6. Security Considerations 507 TBD 509 7. IANA Considerations 511 IANA is requested to make the following allocation for the URIs in 512 the "ns" subregistry within the "IETF XML Registry" [RFC3688]: 514 -------------------------------------------------------------------- 515 URI: urn:ietf:params:xml:ns:yang:ietf-network-slice-mapping 516 Registrant Contact: The IESG. 517 XML: N/A, the requested URI is an XML namespace. 518 -------------------------------------------------------------------- 520 IANA is requested to make the following allocation for the YANG 521 module in the "YANG Module Names" registry [RFC6020]: 523 -------------------------------------------------------------------- 524 name: ietf-network-slice-mapping 525 namespace: urn:ietf:params:xml:ns:yang:ietf-network-slice-mapping 526 prefix: ietf-nsm 527 reference: RFC XXXX 528 -------------------------------------------------------------------- 530 8. References 532 8.1. Normative References 534 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 535 Requirement Levels", BCP 14, RFC 2119, 536 DOI 10.17487/RFC2119, March 1997, 537 . 539 [RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688, 540 DOI 10.17487/RFC3688, January 2004, 541 . 543 [RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for 544 the Network Configuration Protocol (NETCONF)", RFC 6020, 545 DOI 10.17487/RFC6020, October 2010, 546 . 548 [RFC7950] Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language", 549 RFC 7950, DOI 10.17487/RFC7950, August 2016, 550 . 552 [RFC8340] Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams", 553 BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018, 554 . 556 [RFC8345] Clemm, A., Medved, J., Varga, R., Bahadur, N., 557 Ananthakrishnan, H., and X. Liu, "A YANG Data Model for 558 Network Topologies", RFC 8345, DOI 10.17487/RFC8345, March 559 2018, . 561 [RFC9182] Barguil, S., Gonzalez de Dios, O., Ed., Boucadair, M., 562 Ed., Munoz, L., and A. Aguado, "A YANG Network Data Model 563 for Layer 3 VPNs", RFC 9182, DOI 10.17487/RFC9182, 564 February 2022, . 566 [I-D.ietf-teas-ietf-network-slice-nbi-yang] 567 Wu, B., Dhody, D., Rokui, R., Saad, T., and L. Han, "IETF 568 Network Slice Service YANG Model", Work in Progress, 569 Internet-Draft, draft-ietf-teas-ietf-network-slice-nbi- 570 yang-00, 29 September 2021, 571 . 574 [I-D.ietf-teas-te-service-mapping-yang] 575 Lee, Y., Dhody, D., Fioccola, G., Wu, Q., Ceccarelli, D., 576 and J. Tantsura, "Traffic Engineering (TE) and Service 577 Mapping YANG Model", Work in Progress, Internet-Draft, 578 draft-ietf-teas-te-service-mapping-yang-09, 24 October 579 2021, . 582 [I-D.ietf-opsawg-l2nm] 583 Barguil, S., Dios, O. G. D., Boucadair, M., and L. A. 584 Munoz, "A Layer 2 VPN Network YANG Model", Work in 585 Progress, Internet-Draft, draft-ietf-opsawg-l2nm-12, 22 586 November 2021, . 589 [I-D.wd-teas-nrp-yang] 590 Wu, B., Dhody, D., and Y. Cheng, "A YANG Data Model for 591 Network Resource Partition (NRP)", Work in Progress, 592 Internet-Draft, draft-wd-teas-nrp-yang-00, 30 January 593 2022, . 596 [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 597 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, 598 May 2017, . 600 8.2. Informative References 602 [RFC8453] Ceccarelli, D., Ed. and Y. Lee, Ed., "Framework for 603 Abstraction and Control of TE Networks (ACTN)", RFC 8453, 604 DOI 10.17487/RFC8453, August 2018, 605 . 607 [I-D.ietf-teas-ietf-network-slices] 608 Farrel, A., Gray, E., Drake, J., Rokui, R., Homma, S., 609 Makhijani, K., Contreras, L. M., and J. Tantsura, 610 "Framework for IETF Network Slices", Work in Progress, 611 Internet-Draft, draft-ietf-teas-ietf-network-slices-05, 25 612 October 2021, . 615 [I-D.bestbar-teas-ns-packet] 616 Saad, T., Beeram, V. P., Dong, J., Wen, B., Ceccarelli, 617 D., Halpern, J., Peng, S., Chen, R., Liu, X., Contreras, 618 L. M., Rokui, R., and L. Jalil, "Realizing Network Slices 619 in IP/MPLS Networks", Work in Progress, Internet-Draft, 620 draft-bestbar-teas-ns-packet-08, 2 February 2022, 621 . 624 Appendix A. Acknowledgments 626 Thanks to Jie Dong for the initial discussion behind this document. 628 Appendix B. Examples 630 TO be added in future revisions. 632 Authors' Addresses 634 Dhruv Dhody 635 Huawei Technologies 636 Divyashree Techno Park, Whitefield 637 Bangalore 560066 638 India 639 Email: dhruv.ietf@gmail.com 641 Bo Wu 642 Huawei Technologies 643 101 Software Avenue, Yuhua District 644 Nanjing 645 210012 646 China 647 Email: lana.wubo@huawei.com