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Zhuang 4 Intended status: Standards Track Huawei Technologies 5 Expires: June 23, 2016 X. Liu 6 Ericsson 7 J. Haas 8 S. Esale 9 Juniper Networks 10 B. Wen 11 Comcast 12 December 21, 2015 14 Yang Data Model for BGP/MPLS IP VPN 15 draft-li-bess-l3vpn-yang-01 17 Abstract 19 This document defines a YANG data model that can be used to configure 20 and manage L3VPN (BGP/MPLS IP VPN). 22 Requirements Language 24 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 25 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 26 document are to be interpreted as described in RFC 2119 [RFC2119]. 28 Status of This Memo 30 This Internet-Draft is submitted in full conformance with the 31 provisions of BCP 78 and BCP 79. 33 Internet-Drafts are working documents of the Internet Engineering 34 Task Force (IETF). Note that other groups may also distribute 35 working documents as Internet-Drafts. The list of current Internet- 36 Drafts is at http://datatracker.ietf.org/drafts/current/. 38 Internet-Drafts are draft documents valid for a maximum of six months 39 and may be updated, replaced, or obsoleted by other documents at any 40 time. It is inappropriate to use Internet-Drafts as reference 41 material or to cite them other than as "work in progress." 43 This Internet-Draft will expire on June 23, 2016. 45 Copyright Notice 47 Copyright (c) 2015 IETF Trust and the persons identified as the 48 document authors. All rights reserved. 50 This document is subject to BCP 78 and the IETF Trust's Legal 51 Provisions Relating to IETF Documents 52 (http://trustee.ietf.org/license-info) in effect on the date of 53 publication of this document. Please review these documents 54 carefully, as they describe your rights and restrictions with respect 55 to this document. Code Components extracted from this document must 56 include Simplified BSD License text as described in Section 4.e of 57 the Trust Legal Provisions and are provided without warranty as 58 described in the Simplified BSD License. 60 Table of Contents 62 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 63 2. Definitions and Acronyms . . . . . . . . . . . . . . . . . . 3 64 3. Design of the L3VPN Model . . . . . . . . . . . . . . . . . . 3 65 3.1. Overview . . . . . . . . . . . . . . . . . . . . . . . . 3 66 3.2. VPN Instance Configuration . . . . . . . . . . . . . . . 4 67 3.2.1. Per-Instance Configuration . . . . . . . . . . . . . 4 68 3.2.2. Address Family Configuration of L3VPN Instance . . . 4 69 3.3. Yang Tree of L3VPN Yang Model . . . . . . . . . . . . . . 5 70 4. L3VPN YANG Model . . . . . . . . . . . . . . . . . . . . . . 7 71 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15 72 6. Security Considerations . . . . . . . . . . . . . . . . . . . 15 73 7. Normative References . . . . . . . . . . . . . . . . . . . . 15 74 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 16 76 1. Introduction 78 YANG [RFC6020] is a data definition language that was introduced to 79 define the contents of a conceptual data store that allows networked 80 devices to be managed using NETCONF [RFC6241]. YANG is proving 81 relevant beyond its initial confines, as bindings to other interfaces 82 (e.g. ReST) and encodings other than XML (e.g. JSON) are being 83 defined. Furthermore, YANG data models can be used as the basis of 84 implementation for other interfaces, such as CLI and programmatic 85 APIs. 87 This document defines a YANG data model that can be used to configure 88 and manage L3VPN (BGP/MPLS IP VPN) [RFC4364]. 90 2. Definitions and Acronyms 92 AF: Address Family 94 BGP: Border Gateway Protocol 96 JSON: JavaScript Object Notation 98 L3VPN: Layer 3 VPN 100 NETCONF: Network Configuration Protocol 102 ReST: Representational State Transfer, a style of stateless interface 103 and protocol that is generally carried over HTTP 105 YANG: A data definition language for NETCONF 107 3. Design of the L3VPN Model 109 3.1. Overview 111 The L3VPN Yang module is to augment the routing instance Yang models 112 proposed by the draft [I-D.ietf-netmod-routing-cfg]. It introduced 113 the "l3vpn"container to define augmented parameters which can be 114 applied for VRF Routing Instance and support both the IPv4 and IPv6 115 address families. The overview of the "l3vpn" container is shown in 116 the following figure: 118 module: ietf-l3vpn 119 augment /rt:routing/rt:routing-instance: 120 +--rw l3vpn 121 +--rw ipv4-family 122 | +--rw bgp-parameters 123 | | +--rw common 124 | | +--rw route-distinguisher? string 125 | | +--rw vpn-targets* [rt-value] 126 | | +--rw rt-value string 127 | | +--rw rt-type bgp-rt-type 128 | ...... 129 +--rw ipv6-family 130 +--rw bgp-parameters 131 | +--rw common 132 | +--rw route-distinguisher? string 133 | +--rw vpn-targets* [rt-value] 134 | +--rw rt-value string 135 | +--rw rt-type bgp-rt-type 136 ...... 138 L3VPN inteface parameters can reuse those parameters defined by 139 [I-D.ietf-netmod-routing-cfg]. 141 BGP Protocols parameters for L3VPN is defined by the draft 142 [I-D.ietf-idr-bgp-model]. The augment may be defined in the future 143 version if necessary. 145 3.2. VPN Instance Configuration 147 An instance is created to comprise the VPN forwarding information for 148 each VPN in a BGP/MPLS IP VPN. This instance is called a VPN 149 instance or a VPN routing and forwarding (VRF) table. It is also 150 called a per-site forwarding table in [RFC4364]. VPN instances must 151 be created in all BGP/MPLS IP VPN solutions. VPN instances support 152 both the IPv4 and IPv6 address families. 154 VPN instance configuration consists of the following components : 156 o Per-Instance Configuration : that contains the common writable 157 configuration objects for VPN instance IPv4 and IPv6 address family. 159 o Address Family Configuration of L3VPN Instance: that contains the 160 address family specific writable configuration objects. 162 3.2.1. Per-Instance Configuration 164 Per-instance parameters is defined by [I-D.ietf-netmod-routing-cfg] 165 including instance name, description, etc. 167 3.2.2. Address Family Configuration of L3VPN Instance 169 l3vpn container contains the address family specific writable 170 configuration objects, such as route-distinguisher, vpn-targets, 171 apply-label-mode, etc. The parameters should be consistent between 172 IPv4 family and IPv6 family. 174 +--rw l3vpn 175 +--rw ipv4-family 176 | +--rw bgp-parameters 177 | | +--rw common 178 | | +--rw route-distinguisher? string 179 | | +--rw vpn-targets* [rt-value] 180 | | +--rw rt-value string 181 | | +--rw rt-type bgp-rt-type 182 | +--rw apply-label-mode? apply-label-mode-def 183 | +--rw import-route-policy? string 184 | +--rw export-route-policy? string 185 | +--rw tunnel-policy? string 186 | +--rw prefix-limit 187 | | +--rw prefix-limit-number? uint32 188 | | +--rw (prefix-limit-action)? 189 | | +--:(enable-alert-percent) 190 | | | +--rw alert-percent-value? uint8 191 | | | +--rw route-unchanged? boolean 192 | | +--:(enable-simple-alert) 193 | | +--rw simple-alert? boolean 194 | +--rw routing-table-limit 195 | | +--rw routing-table-limit-number? uint32 196 | | +--rw (routing-table-limit-action)? 197 | | +--:(enable-alert-percent) 198 | | | +--rw alert-percent-value? uint8 199 | | +--:(enable-simple-alert) 200 | | +--rw simple-alert? boolean 201 | +--rw import-global-rib 202 | +--rw protocol? enumeration 203 | +--rw processId? uint32 204 | +--rw bgp-valid-route? boolean 205 | +--rw route-policy-name? string 206 +--rw ipv6-family 207 ...... 209 3.3. Yang Tree of L3VPN Yang Model 211 The Yang tree of L3VPn Yang model is shown in the following figure: 213 module: ietf-l3vpn 214 augment /rt:routing/rt:routing-instance: 215 +--rw l3vpn 216 +--rw ipv4-family 217 | +--rw bgp-parameters 218 | | +--rw common 219 | | +--rw route-distinguisher? string 220 | | +--rw vpn-targets* [rt-value] 221 | | +--rw rt-value string 222 | | +--rw rt-type bgp-rt-type 223 | +--rw apply-label-mode? apply-label-mode-def 224 | +--rw import-route-policy? string 225 | +--rw export-route-policy? string 226 | +--rw tunnel-policy? string 227 | +--rw prefix-limit 228 | | +--rw prefix-limit-number? uint32 229 | | +--rw (prefix-limit-action)? 230 | | +--:(enable-alert-percent) 231 | | | +--rw alert-percent-value? uint8 232 | | | +--rw route-unchanged? boolean 233 | | +--:(enable-simple-alert) 234 | | +--rw simple-alert? boolean 235 | +--rw routing-table-limit 236 | | +--rw routing-table-limit-number? uint32 237 | | +--rw (routing-table-limit-action)? 238 | | +--:(enable-alert-percent) 239 | | | +--rw alert-percent-value? uint8 240 | | +--:(enable-simple-alert) 241 | | +--rw simple-alert? boolean 242 | +--rw import-global-rib 243 | +--rw protocol? enumeration 244 | +--rw processId? uint32 245 | +--rw bgp-valid-route? boolean 246 | +--rw route-policy-name? string 247 +--rw ipv6-family 248 +--rw bgp-parameters 249 | +--rw common 250 | +--rw route-distinguisher? string 251 | +--rw vpn-targets* [rt-value] 252 | +--rw rt-value string 253 | +--rw rt-type bgp-rt-type 254 +--rw apply-label-mode? apply-label-mode-def 255 +--rw import-route-policy? string 256 +--rw export-route-policy? string 257 +--rw tunnel-policy? string 258 +--rw prefix-limit 259 | +--rw prefix-limit-number? uint32 260 | +--rw (prefix-limit-action)? 261 | +--:(enable-alert-percent) 262 | | +--rw alert-percent-value? uint8 263 | | +--rw route-unchanged? boolean 264 | +--:(enable-simple-alert) 265 | +--rw simple-alert? boolean 266 +--rw routing-table-limit 267 | +--rw routing-table-limit-number? uint32 268 | +--rw (routing-table-limit-action)? 269 | +--:(enable-alert-percent) 270 | | +--rw alert-percent-value? uint8 271 | +--:(enable-simple-alert) 272 | +--rw simple-alert? boolean 273 +--rw import-global-rib 274 +--rw protocol? enumeration 275 +--rw processId? uint32 276 +--rw bgp-valid-route? boolean 277 +--rw route-policy-name? string 279 4. L3VPN YANG Model 281 //L3VPN YANG MODEL 282 file "ietf-l3vpn.yang" 283 module ietf-l3vpn { 284 namespace "urn:ietf:params:xml:ns:yang:ietf-l3vpn"; 285 // replace with IANA namespace when assigned 286 prefix "l3vpn"; 288 import ietf-routing { 289 prefix "rt"; 290 //draft-ietf-netmod-routing-cfg-19 291 } 293 organization "IETF BGP Enabled Services WG"; 294 contact "draft-li-bess-l3vpn-yang@tools.ietf.org"; 295 description 296 "This YANG module defines the generic configuration data 297 for L3VPN service. 299 Terms and Acronyms 301 BGP (bgp): Border Gateway Protocol 302 IPv4 (ipv4):Internet Protocol Version 4 303 IPv6 (ipv6): Internet Protocol Version 6 305 "; 307 revision 2015-10-09 { 308 description 309 "Initial revision."; 310 reference "RFC4271, RFC4364, RFC4365, RFC4760."; 311 } 313 /* typedefs */ 315 typedef bgp-rt-type { 316 type enumeration { 317 enum import { 318 description "For import"; 319 } 320 enum export { 321 description "For export"; 322 } 323 enum both { 324 description "For both import and export"; 325 } 326 } 327 description "BGP route-target type. Import from BGP YANG."; 328 } 330 typedef apply-label-mode-def { 331 type enumeration { 332 enum "per-route" { 333 value 0; 334 description 335 "By default, the VPN instance IPv4 address family 336 assigns a unique label to each route to be sent 337 to the peer PE."; 338 } 339 enum "per-instance" { 340 value 1; 341 description 342 "The apply-label per-instance command enables the 343 one-label-per-VPN-instance mode."; 344 } 345 } 346 description "..."; 347 } 349 typedef routing-instance-type-ref { 350 type leafref { 351 path "/rt:routing/rt:routing-instance/rt:type"; 352 } 353 description 354 "This type is used for leafs that reference a routing 355 instance configuration."; 356 } 358 grouping bgp-parameters-grp { 359 description 360 "BGP parameters grouping."; 361 container bgp-parameters { 362 description 363 "Parameters for BGP."; 364 container common { 365 description 366 "Common BGP parameters."; 367 leaf route-distinguisher { 368 type string; 369 description "BGP RD."; 370 } 371 list vpn-targets { 372 key rt-value; 373 description 374 "Route Targets."; 375 leaf rt-value { 376 type string; 377 description 378 "Route-Target value."; 379 } 380 leaf rt-type { 381 type bgp-rt-type; 382 mandatory true; 383 description 384 "Type of RT."; 385 } 386 } 387 } 388 } 389 } 391 grouping vpn-af-config { 392 description 393 "A set of configuration parameters that is applicable to both 394 IPv4 and IPv6 address family for a VPN instance ."; 396 leaf apply-label-mode { 397 type apply-label-mode-def; 398 default "per-route"; 399 description "."; 400 } 402 leaf import-route-policy { 403 type string { 404 length "1..40"; 405 } 406 description 407 "The import route-policy command associates a VPN instance 408 enabled with the IPv4 or IPv6 address family with an 409 import routing policy. 410 Only one import routing policy can be associated with a 411 VPN instance enabled with the IPv4 or IPv6 address family. 412 If the import route-policy command is run more than once, 413 the latest configuration overrides the previous ones."; 414 } 416 leaf export-route-policy { 417 type string { 418 length "1..40"; 419 } 420 description 421 "The export route-policy command associates a VPN instance 422 enabled with the IPv4 or IPv6 address family with an 423 export routing policy. 424 Only one export routing policy can be associated with a 425 VPN instance enabled with the IPv4 or IPv6 address family. 426 If the export route-policy command is run more than once, 427 the latest configuration overrides the previous ones."; 428 } 430 leaf tunnel-policy { 431 type string; 432 description 433 "Tunnel policy name."; 434 } 436 container prefix-limit { 437 description 438 "The prefix limit command sets a limit on the maximum 439 number of prefixes supported in the existing VPN 440 instance, preventing the PE from importing excessive 441 VPN route prefixes."; 443 leaf prefix-limit-number { 444 type uint32 { 445 range "1..4294967295"; 446 } 447 description 448 "Specifies the maximum number of prefixes supported in the 449 VPN instance IPv4 or IPv6 address family."; 450 } 452 choice prefix-limit-action { 453 description "."; 454 case enable-alert-percent { 455 leaf alert-percent-value { 456 type uint8 { 457 range "1..100"; 458 } 459 description 460 "Specifies the proportion of the alarm threshold to the 461 maximum number of prefixes."; 462 } 463 leaf route-unchanged { 464 type boolean; 465 default "false"; 466 description 467 "Indicates that the routing table remains unchanged. 468 By default, route-unchanged is not configured. When 469 the number of prefixes in the routing table is 470 greater than the value of the parameter number, 471 routes are processed as follows: 472 (1)If route-unchanged is configured, routes in the 473 routing table remain unchanged. 474 (2)If route-unchanged is not configured, all routes 475 in the routing table are deleted and then 476 re-added."; 477 } 478 } 479 case enable-simple-alert { 480 leaf simple-alert { 481 type boolean; 482 default "false"; 483 description 484 "Indicates that when the number of VPN route prefixes 485 exceeds number, prefixes can still join the VPN 486 routing table and alarms are displayed."; 487 } 488 } 489 } 490 } 492 container routing-table-limit { 493 description 494 "The routing-table limit command sets a limit on the maximum 495 number of routes that the IPv4 or IPv6 address family of a 496 VPN instance can support. 497 By default, there is no limit on the maximum number of 498 routes that the IPv4 or IPv6 address family of a VPN 499 instance can support, but the total number of private 500 network and public network routes on a device cannot 501 exceed the allowed maximum number of unicast routes."; 503 leaf routing-table-limit-number { 504 type uint32 { 505 range "1..4294967295"; 506 } 507 description 508 "Specifies the maximum number of routes supported by a 509 VPN instance. "; 510 } 512 choice routing-table-limit-action { 513 description "."; 514 case enable-alert-percent { 515 leaf alert-percent-value { 516 type uint8 { 517 range "1..100"; 518 } 519 description 520 "Specifies the percentage of the maximum number of 521 routes. When the maximum number of routes that join 522 the VPN instance is up to the value 523 (number*alert-percent)/100, the system prompts 524 alarms. The VPN routes can be still added to the 525 routing table, but after the number of routes 526 reaches number, the subsequent routes are 527 dropped."; 528 } 529 } 530 case enable-simple-alert { 531 leaf simple-alert { 532 type boolean; 533 description 534 "Indicates that when VPN routes exceed number, routes 535 can still be added into the routing table, but the 536 system prompts alarms. 537 However, after the total number of VPN routes and 538 network public routes reaches the unicast route limit 539 specified in the License, the subsequent VPN routes 540 are dropped."; 541 } 542 } 543 } 544 } 546 container import-global-rib { 547 description 548 "Route Leaking from a Global Routing Table into a VRF."; 550 leaf protocol { 551 type enumeration { 552 enum ALL { 553 value "0"; 554 description "ALL:"; 555 } 556 enum Direct { 557 value "1"; 558 description "Direct:"; 559 } 560 enum OSPF { 561 value "2"; 562 description "OSPF:"; 563 } 564 enum ISIS { 565 value "3"; 566 description "ISIS:"; 567 } 568 enum Static { 569 value "4"; 570 description "Static:"; 571 } 572 enum RIP { 573 value "5"; 574 description "RIP:"; 575 } 576 enum BGP { 577 value "6"; 578 description "BGP:"; 579 } 580 enum OSPFV3 { 581 value "7"; 582 description "OSPFV3:"; 583 } 584 enum RIPNG { 585 value "8"; 586 description "RIPNG:"; 587 } 588 enum INVALID { 589 value "9"; 590 description "INVALID:"; 591 } 592 } 593 description 594 "Specifies the protocol from which routes are imported. 595 At present, In the IPv4 unicast address family view, 596 the protocol can be IS-IS,static, direct and BGP."; 597 } 599 leaf processId { 600 type uint32 { 601 range "0..4294967295"; 602 } 603 default "0"; 604 description 605 "Specifies the process ID if the protocol from routes 606 are imported is IS-IS."; 607 } 609 leaf bgp-valid-route { 610 type boolean; 611 description "."; 612 } 614 leaf route-policy-name { 615 type string; 616 description 617 "Policy Id for import routes"; 618 } 620 } 621 } 623 augment "/rt:routing/rt:routing-instance" { 624 description "."; 625 container l3vpn { 626 when "routing-instance-type-ref = 'vrf-routing-instance'" { 627 description "."; 628 } 629 description "."; 630 container ipv4-family { 631 description 632 "The IPv4 address family is enabled for the VPN 633 instance."; 635 uses bgp-parameters-grp; 636 uses vpn-af-config; 637 } 639 container ipv6-family { 640 description 641 "The IPv6 address family is enabled for the VPN 642 instance."; 644 uses bgp-parameters-grp; 645 uses vpn-af-config; 646 } 647 } //End of case type 649 } //End of augment "/rt:routing/rt:routing-instance" 651 } 652 654 5. IANA Considerations 656 This document makes no request of IANA. 658 6. Security Considerations 660 This document does not introduce any new security risk. 662 7. Normative References 664 [I-D.ietf-idr-bgp-model] 665 Shaikh, A., Shakir, R., Patel, K., Hares, S., D'Souza, K., 666 Bansal, D., Clemm, A., Alex, A., Jethanandani, M., and X. 667 Liu, "BGP Model for Service Provider Networks", draft- 668 ietf-idr-bgp-model-00 (work in progress), July 2015. 670 [I-D.ietf-netmod-routing-cfg] 671 Lhotka, L. and A. Lindem, "A YANG Data Model for Routing 672 Management", draft-ietf-netmod-routing-cfg-20 (work in 673 progress), October 2015. 675 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 676 Requirement Levels", BCP 14, RFC 2119, 677 DOI 10.17487/RFC2119, March 1997, 678 . 680 [RFC4271] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A 681 Border Gateway Protocol 4 (BGP-4)", RFC 4271, 682 DOI 10.17487/RFC4271, January 2006, 683 . 685 [RFC4364] Rosen, E. and Y. Rekhter, "BGP/MPLS IP Virtual Private 686 Networks (VPNs)", RFC 4364, DOI 10.17487/RFC4364, February 687 2006, . 689 [RFC4760] Bates, T., Chandra, R., Katz, D., and Y. Rekhter, 690 "Multiprotocol Extensions for BGP-4", RFC 4760, 691 DOI 10.17487/RFC4760, January 2007, 692 . 694 [RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for 695 the Network Configuration Protocol (NETCONF)", RFC 6020, 696 DOI 10.17487/RFC6020, October 2010, 697 . 699 [RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed., 700 and A. Bierman, Ed., "Network Configuration Protocol 701 (NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011, 702 . 704 Authors' Addresses 706 Zhenbin Li 707 Huawei Technologies 708 Huawei Bld., No.156 Beiqing Rd. 709 Beijing 100095 710 China 712 Email: lizhenbin@huawei.com 714 Shunwan Zhuang 715 Huawei Technologies 716 Huawei Bld., No.156 Beiqing Rd. 717 Beijing 100095 718 China 720 Email: zhuangshunwan@huawei.com 722 Xufeng Liu 723 Ericsson 724 1595 Spring Hill Road, Suite 500 725 Vienna, VA 22182 726 USA 728 Email: xufeng.liu@ericsson.com 730 Jeffrey Haas 731 Juniper Networks 733 Email: jhaas@juniper.net 735 Santosh Esale 736 Juniper Networks 737 1194 N. Mathilda Ave. 738 Sunnyvale, CA 94089 739 US 741 Email: sesale@juniper.net 742 Bin Wen 743 Comcast 745 Email: Bin_Wen@cable.comcast.com