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Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Working Group A. Clemm 3 Internet-Draft J. Medved 4 Intended status: Standards Track Cisco 5 Expires: December 14, 2016 R. Varga 6 T. Tkacik 7 Pantheon Technologies SRO 8 X. Liu 9 Kuatro Technologies 10 I. Bryskin 11 Huawei 12 A. Guo 13 Adva Optical 14 H. Ananthakrishnan 15 Packet Design 16 N. Bahadur 17 Bracket Computing 18 V. Beeram 19 Juniper Networks 20 June 12, 2016 22 A YANG Data Model for Layer 3 Topologies 23 draft-ietf-i2rs-yang-l3-topology-02.txt 25 Abstract 27 This document defines a YANG data model for layer 3 network 28 topologies. 30 Status of This Memo 32 This Internet-Draft is submitted in full conformance with the 33 provisions of BCP 78 and BCP 79. 35 Internet-Drafts are working documents of the Internet Engineering 36 Task Force (IETF). Note that other groups may also distribute 37 working documents as Internet-Drafts. The list of current Internet- 38 Drafts is at http://datatracker.ietf.org/drafts/current/. 40 Internet-Drafts are draft documents valid for a maximum of six months 41 and may be updated, replaced, or obsoleted by other documents at any 42 time. It is inappropriate to use Internet-Drafts as reference 43 material or to cite them other than as "work in progress." 45 This Internet-Draft will expire on December 14, 2016. 47 Copyright Notice 49 Copyright (c) 2016 IETF Trust and the persons identified as the 50 document authors. All rights reserved. 52 This document is subject to BCP 78 and the IETF Trust's Legal 53 Provisions Relating to IETF Documents 54 (http://trustee.ietf.org/license-info) in effect on the date of 55 publication of this document. Please review these documents 56 carefully, as they describe your rights and restrictions with respect 57 to this document. Code Components extracted from this document must 58 include Simplified BSD License text as described in Section 4.e of 59 the Trust Legal Provisions and are provided without warranty as 60 described in the Simplified BSD License. 62 This document may contain material from IETF Documents or IETF 63 Contributions published or made publicly available before November 64 10, 2008. The person(s) controlling the copyright in some of this 65 material may not have granted the IETF Trust the right to allow 66 modifications of such material outside the IETF Standards Process. 67 Without obtaining an adequate license from the person(s) controlling 68 the copyright in such materials, this document may not be modified 69 outside the IETF Standards Process, and derivative works of it may 70 not be created outside the IETF Standards Process, except to format 71 it for publication as an RFC or to translate it into languages other 72 than English. 74 Table of Contents 76 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 77 2. Definitions and Acronyms . . . . . . . . . . . . . . . . . . 4 78 3. Model overview . . . . . . . . . . . . . . . . . . . . . . . 5 79 3.1. Model structure . . . . . . . . . . . . . . . . . . . . . 5 80 3.2. Layer 3 Unicast - IGP . . . . . . . . . . . . . . . . . . 6 81 3.3. OSPF Topology . . . . . . . . . . . . . . . . . . . . . . 7 82 3.4. IS-IS Topology . . . . . . . . . . . . . . . . . . . . . 9 83 4. Layer 3 Unicast IGP Topology YANG Module . . . . . . . . . . 10 84 5. OSPF Topology YANG Module . . . . . . . . . . . . . . . . . . 19 85 6. ISIS Topology YANG Module . . . . . . . . . . . . . . . . . . 26 86 7. Security Considerations . . . . . . . . . . . . . . . . . . . 31 87 8. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 31 88 9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 32 89 10. References . . . . . . . . . . . . . . . . . . . . . . . . . 32 90 10.1. Normative References . . . . . . . . . . . . . . . . . . 32 91 10.2. Informative References . . . . . . . . . . . . . . . . . 33 92 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 33 94 1. Introduction 96 This document introduces a YANG [RFC6020] [RFC6991] 97 [I-D.draft-ietf-netmod-rfc6020bis] data model for Layer 3 network 98 topologies. The model allows an application to have a holistic view 99 of the topology of a Layer 3 network, all contained in a single 100 conceptual YANG datastore. The data model builds on top of, and 101 augments, the data model for network topologies defined in 102 [I-D.draft-ietf-i2rs-yang-network-topo]. An earlier revision of that 103 Internet Draft contained not just the general model for network 104 topologies, but also the model for layer 3 network topologies that is 105 being specified here. However, we decided to "split" the earlier 106 draft to separate the truly general aspects of a topology data model, 107 which apply to any type of topology, from the application of this 108 model to a particular domain, here: a Layer 3 network. 110 Specific topology types that are covered in this document include 111 Layer 3 Unicast IGP, IS-IS [RFC1195], and OSPF [RFC2178]. In 112 addition, this documents defines a set of traffic engineering 113 extensions. 115 There are multiple applications for such a data model and a number of 116 use cases have been defined in section 6 of 117 [I-D.draft-ietf-i2rs-usecase-reqs-summary]. For example, nodes 118 within the network can use the data model to capture their 119 understanding of the overall network topology and expose it to a 120 network controller. A network controller can then use the 121 instantiated topology data to compare and reconcile its own view of 122 the network topology with that of the network elements that it 123 controls. Alternatively, nodes within the network could propagate 124 this understanding to compare and reconcile this understanding either 125 amongst themselves or with help of a controller. Beyond the network 126 element itself, a network controller might even use the data model to 127 represent its view of the topology that it controls and expose it to 128 applications north of itself. 130 There are several reasons to choose YANG to define the data model. 131 Data defined using YANG can be exposed by a server to client 132 applications and controllers via Netconf [RFC6241] or via a ReST-like 133 Interface [I-D.draft-ietf-netconf-restconf] 134 [I-D.draft-ietf-netmod-yang-json]. The fact that it can be used with 135 different protocols and interfaces provides for a degree of "future- 136 proofing" of model implementations. Also, YANG can serve as the 137 basis for model-driven toolchains, such as used in the Open Daylight 138 project. 140 The data model is defined in several YANG modules: 142 o Module "ietf-l3-unicast-igp-topology" defines a model for Layer 3 143 Unicast IGP topologies. To do so, it augments general network 144 topology model defined in [I-D.draft-ietf-i2rs-yang-network-topo] 145 with information specific to Layer 3 Unicast IGP. In doing so, it 146 also illustrates the extension patterns associated with extending 147 respectively augmenting the general topology model to meet the 148 needs of a specific topology. 150 o Module "ietf-ospf-topology" defines a topology model for OSPF, 151 building on and extending the Layer 3 Unicast IGP topology model. 152 It serves as an example of how the general topology model can be 153 refined across multiple levels. 155 o Module "ietf-isis-topology" defines a topology model for IS-IS, 156 again building on and extending the Layer 3 Unicast IGP topology 157 model. 159 Information that is kept in the Traffic Engineering Database (TED) is 160 specified in a separate model and outside the scope of this 161 specification. 163 2. Definitions and Acronyms 165 Datastore: A conceptual store of instantiated management information, 166 with individual data items represented by data nodes which are 167 arranged in hierarchical manner. 169 Data subtree: An instantiated data node and the data nodes that are 170 hierarchically contained within it. 172 HTTP: Hyper-Text Transfer Protocol 174 IGP: Interior Gateway Protocol 176 IS-IS: Intermediate System to Intermediate System protocol 178 LSP: Label Switched Path 180 NETCONF: Network Configuration Protocol 182 OSPF: Open Shortest Path First, a link state routing protocol 184 URI: Uniform Resource Identifier 186 ReST: Representational State Transfer, a style of stateless interface 187 and protocol that is generally carried over HTTP 189 SRLG: Shared Risk Link Group 190 TED: Traffic Engineering Database 192 YANG: A data definition language for NETCONF 194 3. Model overview 196 This section provides an overview of the Layer 3 network topology 197 model. 199 3.1. Model structure 201 The network topology model is defined by the following YANG modules, 202 whose relationship is roughly depicted in the figure below. The base 203 network topology is included in the diagram for completeness. 205 +-----------------------------+ 206 | +-----------------------+ | 207 | | ietf-network | | 208 | +----------^------------+ | 209 | | | 210 | +-----------------------+ | 211 | | ietf-network-topology | | 212 | +----------+------------+ | 213 +-------------^---------------+ 214 | 215 | 216 +-----------^-------------+ 217 | l3-unicast-igp-topology | 218 +----+---------------+----+ 219 ^ ^ 220 | | 221 | | 222 +--------^-----+ +-----^---------+ 223 | ospf-topology| | isis-topology | 224 +--------------+ +---------------+ 226 Figure 1: Overall model structure 228 YANG modules ietf-network and ietf-network-topology collectively 229 define the basic network topology model. YANG module ietf-l3- 230 unicast-igp-topology augments those models with additional 231 definitions needed to represent Layer 3 Unicast IGP topologies. This 232 module in turn is augmented by YANG modules with additional 233 definitions for OSPF and for IS-IS topologies, ietf-ospf-topology and 234 ietf-isis-topology, respectively. 236 3.2. Layer 3 Unicast - IGP 238 The Layer 3 Unicast IGP topology model is defined by YANG module 239 "ietf-l3-unicast-igp-topology". The model is depicted in the 240 following diagram. Brackets enclose list keys, "rw" means 241 configuration, "ro" operational state data, "?" designates optional 242 nodes, "*" designates nodes that can have multiple instances. 243 Parantheses enclose choice and case nodes. Notifications are not 244 depicted. The prefix "nt:" refers to the YANG module for network 245 topology. 247 module: ietf-l3-unicast-igp-topology 248 augment /nw:networks/nw:network/nw:network-types: 249 +--rw l3-unicast-igp-topology! 250 augment /nw:networks/nw:network: 251 +--rw igp-topology-attributes 252 +--rw name? string 253 +--rw flag* flag-type 254 augment /nw:networks/nw:network/nw:node: 255 +--rw igp-node-attributes 256 +--rw name? inet:domain-name 257 +--rw flag* flag-type 258 +--rw router-id* inet:ip-address 259 +--rw prefix* [prefix] 260 +--rw prefix inet:ip-prefix 261 +--rw metric? uint32 262 +--rw flag* flag-type 263 augment /nw:networks/nw:network/nt:link: 264 +--rw igp-link-attributes 265 +--rw name? string 266 +--rw flag* flag-type 267 +--rw metric? uint32 268 augment /nw:networks/nw:network/nw:node/nt:termination-point: 269 +--rw igp-termination-point-attributes 270 +--rw (termination-point-type)? 271 +--:(ip) 272 | +--rw ip-address* inet:ip-address 273 +--:(unnumbered) 274 +--rw unnumbered-id? uint32 276 The module augments the original ietf-network and ietf-network- 277 topology modules as follows: 279 o A new network topology type is introduced, l3-unicast-igp- 280 topology. The corresponding container augments the network-types 281 of the ietf-network module. 283 o Additional topology attributes are introduced, defined in a 284 grouping, which augments the "network" list of the network module. 285 The attributes include an IGP name, as well as a set of flags 286 (represented through a leaf-list). Each type of flag is 287 represented by a separate identity. This allows to introduce 288 additional flags in augmenting modules that are associated with 289 specific IGP topologies, without needing to revise this module. 291 o Additional data objects for nodes are introduced by augmenting the 292 "node" list of the network module. New objects include again a 293 set of flags, as well as a list of prefixes. Each prefix in turn 294 includes an ip prefix, a metric, and a prefix-specific set of 295 flags. 297 o Links (in the ietf-network-topology module) are augmented with a 298 set of parameters as well, allowing to associate a link with an 299 IGP name, another set of flags, and a link metric. 301 o Termination points (in the ietf-network-topology module as well) 302 are augmented with a choice of IP address or identifier. 304 In addition, the module defines a set of notifications to alert 305 clients of any events concerning links, nodes, prefixes, and 306 termination points. Each notification includes an indication of the 307 type of event, the topology from which it originated, and the 308 affected node, or link, or prefix, or termination point. In 309 addition, as a convenience to applications, additional data of the 310 affected node, or link, or termination point (respectively) is 311 included. While this makes notifications larger in volume than they 312 would need to be, it avoids the need for subsequent retrieval of 313 context information, which also might have changed in the meantime. 315 3.3. OSPF Topology 317 OSPF is the next type of topology represented in the model. OSPF 318 represents a particular type of Layer 3 Unicast IGP. Accordingly, 319 this time the Layer 3 Unicast IGP topology model needs to be 320 extended. The corresponding extensions are introduced in a separate 321 YANG module "ietf-ospf-topology", whose structure is depicted in the 322 following diagram. For the most part, this module augments "ietf-l3- 323 unicast-igp-topology". Like before, brackets enclose list keys, "rw" 324 means configuration, "ro" operational state data, "?" designates 325 optional nodes, "*" designates nodes that can have multiple 326 instances. Parantheses enclose choice and case nodes. A "+" at the 327 end of a line indicates a line break. Notifications respectively 328 augmentations of notifications are not depicted. 330 module: ietf-ospf-topology 331 augment /nw:networks/nw:network/nw:network-types/+ 332 | l3t:l3-unicast-igp-topology: 333 +--rw ospf! 334 augment /nw:networks/nw:network/l3t:igp-topology-attributes: 335 +--rw ospf-topology-attributes 336 +--rw area-id? area-id 337 augment /nw:networks/nw:network/nw:node/l3t:igp-node-attributes: 338 +--rw ospf-node-attributes 339 +--rw (router-type)? 340 | +--:(abr) 341 | | +--rw abr? empty 342 | +--:(asbr) 343 | | +--rw asbr? empty 344 | +--:(internal) 345 | | +--rw internal? empty 346 | +--:(pseudonode) 347 | +--rw pseudonode? empty 348 +--rw dr-interface-id? uint32 349 +--rw multi-topology-id* uint8 350 +--rw capabilities? bits 351 augment /nw:networks/nw:network/nt:link/l3t:igp-link-attributes: 352 +--rw ospf-link-attributes 353 +--rw multi-topology-id? uint8 354 augment /nw:networks/nw:network/nw:node/l3t:igp-node-attributes/+ 355 | l3t:prefix: 356 +--rw ospf-prefix-attributes 357 +--rw forwarding-address? inet:ipv4-address 359 The module augments "ietf-l3-unicast-igp-topology" as follows: 361 o A new topology type for an OSPF topology is introduced. 363 o Additional topology attributes are defined in a new grouping which 364 augments igp-topology-attributes of the ietf-l3-unicast-igp- 365 topology module. The attributes include an OSPF area-id 366 identifying the OSPF area. 368 o Additional data objects for nodes are introduced by augmenting the 369 igp-node-attributes of the l3-unicast-igp-topology module. New 370 objects include router-type, dr-interface-id for pseudonodes, list 371 of multi-topology-ids, ospf node capabilities, and traffic 372 engineering attributes. 374 o Links are augmented with a multi-topology-id and traffic 375 engineering link attributes. 377 o Prefixes are augmented with OSPF specific forwarding address. 379 In addition, the module extends IGP node, link and prefix 380 notifications with OSPF attributes. 382 3.4. IS-IS Topology 384 IS-IS is another type of Layer 3 Unicast IGP. Like OSPF topology, 385 IS-IS topology is defined in a separate module, "ietf-isis-topology", 386 which augments "ietf-l3-unicast-igp-topology". The structure is 387 depicted in the following diagram. Like before, brackets enclose 388 list keys, "rw" means configuration, "ro" operational state data, "?" 389 designates optional nodes, "*" designates nodes that can have 390 multiple instances. Parantheses enclose choice and case nodes. A 391 "+" at the end of a line indicates a line break. Notifications are 392 not depicted. 394 module: ietf-isis-topology 395 augment /nw:networks/nw:network/nw:network-types/+ 396 | l3t:l3-unicast-igp-topology: 397 +--rw isis! 398 augment /nw:networks/nw:network/l3t:igp-topology-attributes: 399 +--rw isis-topology-attributes 400 +--rw net? iso-net-id 401 augment /nw:networks/nw:network/nw:node/l3t:igp-node-attributes: 402 +--rw isis-node-attributes 403 +--rw iso 404 | +--rw iso-system-id? iso-system-id 405 | +--rw iso-pseudonode-id? iso-pseudonode-id 406 +--rw net* iso-net-id 407 +--rw multi-topology-id* uint8 408 +--rw (router-type)? 409 +--:(level-2) 410 | +--rw level-2? empty 411 +--:(level-1) 412 | +--rw level-1? empty 413 +--:(level-1-2) 414 +--rw level-1-2? empty 415 augment /nw:networks/nw:network/nt:link/l3t:igp-link-attributes: 416 +--rw isis-link-attributes 417 +--rw multi-topology-id? uint8 419 The module augments the ietf-l3-unicast-igp-topology as follows: 421 o A new topology type is introduced for isis. 423 o Additional topology attributes are introduced in a new grouping 424 which augments "igp-topology-attributes" of the ietf-l3-unicast- 425 igp-topology module. The attributes include an ISIS NET-id 426 identifying the area. 428 o Additional data objects for nodes are introduced by augmenting 429 "igp-node-attributes" of the ietf-l3-unicast-igp-topology module. 430 New objects include router-type, iso-system-id to identify the 431 router, a list of multi-topology-id, a list of NET ids, and 432 traffic engineering attributes. 434 o Links are augmented with multi-topology-id and traffic engineering 435 link attributes. 437 In addition, the module augments IGP nodes and links with ISIS 438 attributes. 440 4. Layer 3 Unicast IGP Topology YANG Module 442 file "ietf-l3-unicast-igp-topology@2016-06-12.yang" 443 module ietf-l3-unicast-igp-topology { 444 yang-version 1.1; 445 namespace 446 "urn:ietf:params:xml:ns:yang:ietf-l3-unicast-igp-topology"; 447 prefix "l3t"; 448 import ietf-network { 449 prefix "nw"; 450 } 451 import ietf-network-topology { 452 prefix "nt"; 453 } 454 import ietf-inet-types { 455 prefix "inet"; 456 } 458 organization 459 "IETF I2RS (Interface to the Routing System) Working Group"; 461 contact 462 "WG Web: 463 WG List: 465 WG Chair: Susan Hares 466 468 WG Chair: Russ White 469 471 Editor: Alexander Clemm 472 474 Editor: Jan Medved 475 477 Editor: Robert Varga 478 480 Editor: Tony Tkacik 481 483 Editor: Xufeng Liu 484 486 Editor: Igor Bryskin 487 489 Editor: Aihua Guo 490 492 Editor: Nitin Bahadur 493 495 Editor: Hariharan Ananthakrishnan 496 498 Editor: Vishnu Pavan Beeram 499 "; 501 description 502 "This module defines a model for Layer 3 Unicast IGP 503 topologies. 505 Copyright (c) 2016 IETF Trust and the persons identified as 506 authors of the code. All rights reserved. 508 Redistribution and use in source and binary forms, with or 509 without modification, is permitted pursuant to, and subject 510 to the license terms contained in, the Simplified BSD License 511 set forth in Section 4.c of the IETF Trust's Legal Provisions 512 Relating to IETF Documents 513 (http://trustee.ietf.org/license-info). 515 This version of this YANG module is part of 516 draft-ietf-i2rs-yang-network-topo-02; 517 see the RFC itself for full legal notices. 519 NOTE TO RFC EDITOR: Please replace above reference to 520 draft-ietf-i2rs-yang-network-topo-02 with RFC 521 number when published (i.e. RFC xxxx)."; 523 revision "2016-06-12" { 524 description 525 "Initial revision. 526 NOTE TO RFC EDITOR: Please replace the following reference 527 to draft-ietf-i2rs-yang-l3-topology-01 with 528 RFC number when published (i.e. RFC xxxx)."; 529 reference 530 "draft-ietf-i2rs-yang-l3-topology-02"; 531 } 533 typedef igp-event-type { 534 type enumeration { 535 enum "add" { 536 value 0; 537 description 538 "An IGP node or link or prefix or termination-point has 539 been added"; 540 } 541 enum "remove" { 542 value 1; 543 description 544 "An IGP node or link or prefix or termination-point has 545 been removed"; 546 } 547 enum "update" { 548 value 2; 549 description 550 "An IGP node or link or prefix or termination-point has 551 been updated"; 552 } 553 } 554 description "IGP Event type for notifications"; 555 } // igp-event-type 557 identity flag-identity { 558 description "Base type for flags"; 559 } 560 identity undefined-flag { 561 base "flag-identity"; 562 description "Undefined flag"; 563 } 565 typedef flag-type { 566 type identityref { 567 base "flag-identity"; 568 } 569 description "Type for flags"; 570 } 571 grouping network-ref { 572 description 573 "Grouping for an absolute reference to a network topology 574 instance."; 575 leaf network-ref { 576 type leafref { 577 path "/nw:networks/nw:network/nw:network-id"; 578 } 579 description 580 "An absolute reference to a network topology instance."; 581 } 582 } 584 grouping link-ref { 585 description 586 "Grouping for an absolute reference to a link instance."; 587 uses network-ref; 588 leaf link-ref { 589 type leafref { 590 path "/nw:networks/nw:network" 591 +"[nw:network-id = current()/../network-ref]" 592 +"/nt:link/nt:link-id"; 593 } 594 description 595 "An absolute reference to a link instance."; 596 } 597 } 599 grouping node-ref { 600 description 601 "Grouping for an absolute reference to a node instance."; 602 uses network-ref; 603 leaf node-ref { 604 type leafref { 605 path "/nw:networks/nw:network" 606 +"[nw:network-id = current()/../network-ref]" 607 +"/nw:node/nw:node-id"; 608 } 609 description 610 "An absolute reference to a node instance."; 611 } 612 } 614 grouping tp-ref { 615 description 616 "Grouping for an absolute reference to a termination point."; 617 uses node-ref; 618 leaf tp-ref { 619 type leafref { 620 path "/nw:networks/nw:network" 621 +"[nw:network-id = current()/../network-ref]" 622 +"/nw:node[nw:node-id = current()/../node-ref]" 623 +"/nt:termination-point/nt:tp-id"; 624 } 625 description 626 "Grouping for an absolute reference to a termination point."; 627 } 628 } 630 grouping igp-prefix-attributes { 631 description 632 "IGP prefix attributes"; 633 leaf prefix { 634 type inet:ip-prefix; 635 description 636 "IP prefix value"; 637 } 638 leaf metric { 639 type uint32; 640 description 641 "Prefix metric"; 642 } 643 leaf-list flag { 644 type flag-type; 645 description 646 "Prefix flags"; 647 } 648 } 650 grouping l3-unicast-igp-topology-type { 651 description "Identify the topology type to be L3 unicast."; 652 container l3-unicast-igp-topology { 653 presence "indicates L3 Unicast IGP Topology"; 654 description 655 "The presence of the container node indicates L3 Unicast 656 IGP Topology"; 657 } 658 } 660 grouping igp-topology-attributes { 661 description "Topology scope attributes"; 662 container igp-topology-attributes { 663 description "Containing topology attributes"; 664 leaf name { 665 type string; 666 description 667 "Name of the topology"; 668 } 669 leaf-list flag { 670 type flag-type; 671 description 672 "Topology flags"; 673 } 674 } 675 } 677 grouping igp-node-attributes { 678 description "IGP node scope attributes"; 679 container igp-node-attributes { 680 description 681 "Containing node attributes"; 682 leaf name { 683 type inet:domain-name; 684 description 685 "Node name"; 686 } 687 leaf-list flag { 688 type flag-type; 689 description 690 "Node operational flags"; 691 } 692 leaf-list router-id { 693 type inet:ip-address; 694 description 695 "Router-id for the node"; 696 } 697 list prefix { 698 key "prefix"; 699 description 700 "A list of prefixes along with their attributes"; 701 uses igp-prefix-attributes; 702 } 703 } 704 } 706 grouping igp-link-attributes { 707 description 708 "IGP link scope attributes"; 709 container igp-link-attributes { 710 description 711 "Containing link attributes"; 712 leaf name { 713 type string; 714 description 715 "Link Name"; 716 } 717 leaf-list flag { 718 type flag-type; 719 description 720 "Link flags"; 721 } 722 leaf metric { 723 type uint32 { 724 range "0..16777215" { 725 description 726 "This is a metric that can take a 3 byte metric, 727 commonly used in OSPF/ISIS"; 728 } 729 } 730 description 731 "Link Metric"; 732 } 733 } 734 } 736 grouping igp-termination-point-attributes { 737 description "IGP termination point scope attributes"; 738 container igp-termination-point-attributes { 739 description 740 "Containing termination point attributes"; 741 choice termination-point-type { 742 description 743 "Indicates the termination point type"; 744 case ip { 745 leaf-list ip-address { 746 type inet:ip-address; 747 description 748 "IPv4 or IPv6 address"; 749 } 750 } 751 case unnumbered { 752 leaf unnumbered-id { 753 type uint32; 754 description 755 "Unnumbered interface identifier"; 756 } 757 } 758 } 759 } 760 } // grouping igp-termination-point-attributes 762 augment "/nw:networks/nw:network/nw:network-types" { 763 description 764 "Introduce new network type for L3 unicast IGP topology"; 765 uses l3-unicast-igp-topology-type; 766 } 768 augment "/nw:networks/nw:network" { 769 when "nw:network-types/l3-unicast-igp-topology" { 770 description 771 "Augmentation parameters apply only for networks with 772 L3 unicast IGP topology"; 773 } 774 description 775 "Configuration parameters for L3 unicast IPG for the network 776 as a whole"; 777 uses igp-topology-attributes; 778 } 780 augment "/nw:networks/nw:network/nw:node" { 781 when "../nw:network-types/l3-unicast-igp-topology" { 782 description 783 "Augmentation parameters apply only for networks with 784 L3 unicast IGP topology"; 785 } 786 description 787 "Configuration parameters for L3 unicast IPG at the node 788 level"; 789 uses igp-node-attributes; 790 } 792 augment "/nw:networks/nw:network/nt:link" { 793 when "../nw:network-types/l3-unicast-igp-topology" { 794 description 795 "Augmentation parameters apply only for networks with 796 L3 unicast IGP topology"; 797 } 798 description 799 "Augment topology link configuration"; 800 uses igp-link-attributes; 801 } 803 augment "/nw:networks/nw:network/nw:node/" 804 +"nt:termination-point" { 805 when "../../nw:network-types/l3-unicast-igp-topology" { 806 description 807 "Augmentation parameters apply only for networks with 808 L3 unicast IGP topology"; 809 } 810 description "Augment topology termination point configuration"; 811 uses igp-termination-point-attributes; 812 } 814 notification igp-node-event { 815 description 816 "Notification event for IGP node"; 817 leaf igp-event-type { 818 type igp-event-type; 819 description 820 "Event type"; 821 } 822 uses node-ref; 823 uses l3-unicast-igp-topology-type; 824 uses igp-node-attributes; 825 } 827 notification igp-link-event { 828 description 829 "Notification event for IGP link"; 830 leaf igp-event-type { 831 type igp-event-type; 832 description 833 "Event type"; 834 } 835 uses link-ref; 836 uses l3-unicast-igp-topology-type; 837 uses igp-link-attributes; 838 } 840 notification igp-prefix-event { 841 description 842 "Notification event for IGP prefix"; 843 leaf igp-event-type { 844 type igp-event-type; 845 description 846 "Event type"; 847 } 848 uses node-ref; 849 uses l3-unicast-igp-topology-type; 850 container prefix { 851 description 852 "Containing IPG prefix attributes"; 853 uses igp-prefix-attributes; 854 } 855 } 857 notification termination-point-event { 858 description 859 "Notification event for IGP termination point"; 860 leaf igp-event-type { 861 type igp-event-type; 862 description 863 "Event type"; 864 } 865 uses tp-ref; 866 uses l3-unicast-igp-topology-type; 867 uses igp-termination-point-attributes; 868 } 869 } 870 872 5. OSPF Topology YANG Module 874 file "ietf-ospf-topology@2016-06-12.yang" 875 module ietf-ospf-topology { 876 yang-version 1.1; 877 namespace "urn:ietf:params:xml:ns:yang:ietf-ospf-topology"; 878 prefix "ospf"; 880 import ietf-inet-types { 881 prefix "inet"; 882 } 883 import ietf-network { 884 prefix "nw"; 885 } 886 import ietf-network-topology { 887 prefix "nt"; 888 } 889 import ietf-l3-unicast-igp-topology { 890 prefix "l3t"; 891 } 893 organization 894 "IETF I2RS (Interface to the Routing System) Working Group"; 896 contact 897 "WG Web: 898 WG List: 900 WG Chair: Susan Hares 901 903 WG Chair: Russ White 904 906 Editor: Alexander Clemm 907 909 Editor: Jan Medved 910 912 Editor: Robert Varga 913 915 Editor: Tony Tkacik 916 918 Editor: Xufeng Liu 919 921 Editor: Igor Bryskin 922 924 Editor: Aihua Guo 925 927 Editor: Nitin Bahadur 928 930 Editor: Hariharan Ananthakrishnan 931 933 Editor: Vishnu Pavan Beeram 934 "; 936 description 937 "This module defines a model for OSPF network topologies. 939 Copyright (c) 2016 IETF Trust and the persons identified as 940 authors of the code. All rights reserved. 942 Redistribution and use in source and binary forms, with or 943 without modification, is permitted pursuant to, and subject 944 to the license terms contained in, the Simplified BSD License 945 set forth in Section 4.c of the IETF Trust's Legal Provisions 946 Relating to IETF Documents 947 (http://trustee.ietf.org/license-info). 949 This version of this YANG module is part of 950 draft-ietf-i2rs-yang-network-topo-02; 951 see the RFC itself for full legal notices. 953 NOTE TO RFC EDITOR: Please replace above reference to 954 draft-ietf-i2rs-yang-network-topo-02 with RFC 955 number when published (i.e. RFC xxxx)."; 957 revision "2016-06-12" { 958 description 959 "Initial revision. 960 NOTE TO RFC EDITOR: Please replace the following reference 961 to draft-ietf-i2rs-yang-l3-topology-02 with 962 RFC number when published (i.e. RFC xxxx)."; 963 reference 964 "draft-ietf-i2rs-yang-l3-topology-02"; 965 } 967 typedef area-id { 968 type uint32; 969 description 970 "OSPF Area ID"; 971 } 973 grouping ospf-topology-type { 974 description 975 "Identifies the OSPF topology type."; 976 container ospf { 977 presence "indiates OSPF Topology"; 978 description 979 "Its presence identifies the OSPF topology type."; 980 } 981 } 983 augment "/nw:networks/nw:network/nw:network-types/" 984 + "l3t:l3-unicast-igp-topology" { 985 description 986 "Defines the OSPF topology type."; 987 uses ospf-topology-type; 988 } 990 augment "/nw:networks/nw:network/l3t:igp-topology-attributes" { 991 when "../nw:network-types/l3t:l3-unicast-igp-topology/ospf" { 992 description 993 "Augment only for OSPF topology"; 994 } 995 description 996 "Augment topology configuration"; 997 container ospf-topology-attributes { 998 description 999 "Containing topology attributes"; 1000 leaf area-id { 1001 type area-id; 1002 description 1003 "OSPF area ID"; 1004 } 1005 } 1006 } 1008 augment "/nw:networks/nw:network/nw:node/l3t:igp-node-attributes" { 1009 when "../../nw:network-types/l3t:l3-unicast-igp-topology/ospf" { 1010 description 1011 "Augment only for OSPF topology"; 1012 } 1013 description 1014 "Augment node configuration"; 1015 uses ospf-node-attributes; 1016 } 1018 augment "/nw:networks/nw:network/nt:link/l3t:igp-link-attributes" { 1019 when "../../nw:network-types/l3t:l3-unicast-igp-topology/ospf" { 1020 description 1021 "Augment only for OSPF topology"; 1022 } 1023 description 1024 "Augment link configuration"; 1025 uses ospf-link-attributes; 1026 } 1028 augment "/nw:networks/nw:network/nw:node/"+ 1029 "l3t:igp-node-attributes/l3t:prefix" { 1030 when "../../../nw:network-types/l3t:l3-unicast-igp-topology/" 1031 +"ospf" { 1032 description 1033 "Augment only for OSPF topology"; 1034 } 1035 description 1036 "Augment prefix"; 1037 uses ospf-prefix-attributes; 1038 } 1040 grouping ospf-node-attributes { 1041 description 1042 "OSPF node scope attributes"; 1043 container ospf-node-attributes { 1044 description 1045 "Containing node attributes"; 1046 choice router-type { 1047 description 1048 "Indicates router type"; 1049 case abr { 1050 leaf abr { 1051 type empty; 1052 description 1053 "The node is ABR"; 1054 } 1055 } 1056 case asbr { 1057 leaf asbr { 1058 type empty; 1059 description 1060 "The node is ASBR"; 1061 } 1062 } 1063 case internal { 1064 leaf internal { 1065 type empty; 1066 description 1067 "The node is internal"; 1068 } 1069 } 1070 case pseudonode { 1071 leaf pseudonode { 1072 type empty; 1073 description 1074 "The node is pseudonode"; 1075 } 1076 } 1077 } 1078 leaf dr-interface-id { 1079 when "../router-type/pseudonode" { 1080 description 1081 "Valid only for pseudonode"; 1082 } 1083 type uint32; 1084 default "0"; 1085 description 1086 "For pseudonodes, DR interface-id"; 1087 } 1088 leaf-list multi-topology-id { 1089 type uint8 { 1090 range "0..127"; 1091 } 1092 max-elements "128"; 1093 description 1094 "List of Multi-Topology Identifier up-to 128 (0-127). 1095 See RFC 4915"; 1096 } 1097 leaf capabilities { 1098 type bits { 1099 bit graceful-restart-capable { 1100 position 0; 1101 description 1102 "Graceful restart capable"; 1103 } 1104 bit graceful-restart-helper { 1105 position 1; 1106 description 1107 "Graceful restart helper"; 1108 } 1109 bit stub-router-support { 1110 position 2; 1111 description 1112 "Stub router support"; 1113 } 1114 bit traffic-engineering-support { 1115 position 3; 1116 description 1117 "Traffic engineering support"; 1118 } 1119 bit point-to-point-over-lan { 1120 position 4; 1121 description 1122 "Support point to point over LAN"; 1123 } 1124 bit experimental-te { 1125 position 5; 1126 description 1127 "Support experimental traffic engineering"; 1128 } 1129 } 1130 description 1131 "OSPF capabilities as bit vector. RFC 4970"; 1132 } 1133 } 1134 } 1136 grouping ospf-link-attributes { 1137 description 1138 "OSPF link scope attributes"; 1139 container ospf-link-attributes { 1140 description 1141 "Containing OSPF link attributes"; 1142 leaf multi-topology-id { 1143 type uint8 { 1144 range "0..127"; 1145 } 1146 description "Muti topology ID"; 1148 } 1149 } 1150 } // ospf-link-attributes 1152 grouping ospf-prefix-attributes { 1153 description 1154 "OSPF prefix attributes"; 1155 container ospf-prefix-attributes { 1156 description 1157 "Containing prefix attributes"; 1158 leaf forwarding-address { 1159 when "../../l3t:l3-unicast-igp-topology/l3t:ospf/"+ 1160 "l3t:router-type/l3t:asbr" { 1161 description "Valid only for ABSR"; 1162 } 1163 type inet:ipv4-address; 1164 description 1165 "Forwarding address for ABSR"; 1166 } 1167 } 1168 } 1170 augment "/l3t:igp-node-event" { 1171 description 1172 "OSPF node event"; 1173 uses ospf-topology-type; 1174 uses ospf:ospf-node-attributes; 1175 } 1177 augment "/l3t:igp-link-event" { 1178 description 1179 "OSPF link event"; 1180 uses ospf-topology-type; 1181 uses ospf:ospf-link-attributes; 1182 } 1184 augment "/l3t:igp-prefix-event" { 1185 description 1186 "OSPF prefix event"; 1187 uses ospf-topology-type; 1188 uses ospf:ospf-prefix-attributes; 1189 } 1190 } 1192 1194 6. ISIS Topology YANG Module 1196 file "ietf-isis-topology@2016-06-12.yang" 1197 module ietf-isis-topology { 1198 yang-version 1.1; 1199 namespace "urn:ietf:params:xml:ns:yang:ietf-isis-topology"; 1200 prefix "isis"; 1202 import ietf-network { 1203 prefix "nw"; 1204 } 1205 import ietf-network-topology { 1206 prefix "nt"; 1207 } 1208 import ietf-l3-unicast-igp-topology { 1209 prefix "l3t"; 1210 } 1212 organization 1213 "IETF I2RS (Interface to the Routing System) Working Group"; 1215 contact 1216 "WG Web: 1217 WG List: 1219 WG Chair: Susan Hares 1220 1222 WG Chair: Russ White 1223 1225 Editor: Alexander Clemm 1226 1228 Editor: Jan Medved 1229 1231 Editor: Robert Varga 1232 1234 Editor: Tony Tkacik 1235 1237 Editor: Xufeng Liu 1238 1240 Editor: Igor Bryskin 1241 1243 Editor: Aihua Guo 1244 1246 Editor: Nitin Bahadur 1247 1249 Editor: Hariharan Ananthakrishnan 1250 1252 Editor: Vishnu Pavan Beeram 1253 "; 1255 description 1256 "This module defines a model for IS-IS network topologies. 1258 Copyright (c) 2016 IETF Trust and the persons identified as 1259 authors of the code. All rights reserved. 1261 Redistribution and use in source and binary forms, with or 1262 without modification, is permitted pursuant to, and subject 1263 to the license terms contained in, the Simplified BSD License 1264 set forth in Section 4.c of the IETF Trust's Legal Provisions 1265 Relating to IETF Documents 1266 (http://trustee.ietf.org/license-info). 1268 This version of this YANG module is part of 1269 draft-ietf-i2rs-yang-network-topo-02; 1270 see the RFC itself for full legal notices. 1272 NOTE TO RFC EDITOR: Please replace above reference to 1273 draft-ietf-i2rs-yang-network-topo-02 with RFC 1274 number when published (i.e. RFC xxxx)."; 1276 revision "2016-06-12" { 1277 description 1278 "Initial revision. 1279 NOTE TO RFC EDITOR: Please replace the following reference 1280 to draft-ietf-i2rs-yang-l3-topology-02 with 1281 RFC number when published (i.e. RFC xxxx)."; 1282 reference 1283 "draft-ietf-i2rs-yang-l3-topology-02"; 1284 } 1286 typedef iso-system-id { 1287 type string { 1288 pattern '[0-9a-fA-F]{4}(\.[0-9a-fA-F]{4}){2}'; 1289 } 1290 description 1291 "ISO System ID. RFC 1237"; 1292 } 1294 typedef iso-pseudonode-id { 1295 type string { 1296 pattern '[0-9a-fA-F]{2}'; 1297 } 1298 description 1299 "ISO pseudonode id for broadcast network"; 1300 } 1302 typedef iso-net-id { 1303 type string { 1304 pattern '[0-9a-fA-F]{2}((\.[0-9a-fA-F]{4}){6})'; 1305 } 1306 description 1307 "ISO NET ID. RFC 1237"; 1308 } 1310 grouping isis-topology-type { 1311 description 1312 "Identifies the ISIS topology type."; 1313 container isis { 1314 presence "Indicates ISIS Topology"; 1315 description 1316 "Its presence identifies the ISIS topology type."; 1317 } 1318 } 1320 augment "/nw:networks/nw:network/nw:network-types/" 1321 +"l3t:l3-unicast-igp-topology" { 1322 description 1323 "Defines the ISIS topology type."; 1324 uses isis-topology-type; 1325 } 1327 augment "/nw:networks/nw:network/l3t:igp-topology-attributes" { 1328 when "../nw:network-types/l3t:l3-unicast-igp-topology/isis" { 1329 description 1330 "Augment only for ISIS topology"; 1331 } 1332 description 1333 "Augment topology configuration"; 1334 container isis-topology-attributes { 1335 description 1336 "Containing topology attributes"; 1337 leaf net { 1338 type iso-net-id; 1339 description 1340 "ISO NET ID value"; 1341 } 1342 } 1343 } 1345 augment "/nw:networks/nw:network/nw:node/"+ 1346 "l3t:igp-node-attributes" { 1347 when "../../nw:network-types/l3t:l3-unicast-igp-topology/isis" { 1348 description 1349 "Augment only for ISIS topology"; 1350 } 1351 description 1352 "Augment node configuration"; 1353 uses isis-node-attributes; 1354 } 1356 augment "/nw:networks/nw:network/nt:link/l3t:igp-link-attributes" { 1357 when "../../nw:network-types/l3t:l3-unicast-igp-topology/isis" { 1358 description 1359 "Augment only for ISIS topology"; 1360 } 1361 description 1362 "Augment link configuration"; 1363 uses isis-link-attributes; 1364 } 1366 grouping isis-node-attributes { 1367 description 1368 "ISIS node scope attributes"; 1369 container isis-node-attributes { 1370 description 1371 "Containing node attributes"; 1372 container iso { 1373 description 1374 "Containing ISO atrributes"; 1375 leaf iso-system-id { 1376 type iso-system-id; 1377 description 1378 "ISO system ID"; 1379 } 1380 leaf iso-pseudonode-id { 1381 type iso-pseudonode-id; 1382 default "00"; 1383 description 1384 "Pseudonode ID"; 1385 } 1386 } 1387 leaf-list net { 1388 type iso-net-id; 1389 max-elements 3; 1390 description 1391 "List of ISO NET IDs"; 1392 } 1393 leaf-list multi-topology-id { 1394 type uint8 { 1395 range "0..127"; 1396 } 1397 max-elements "128"; 1398 description 1399 "List of Multi Topology Identifier upto 128 (0-127). 1400 RFC 4915"; 1401 } 1402 choice router-type { 1403 description 1404 "Indicates router type"; 1405 case level-2 { 1406 leaf level-2 { 1407 type empty; 1408 description 1409 "Level-2 only"; 1410 } 1411 } 1412 case level-1 { 1413 leaf level-1 { 1414 type empty; 1415 description 1416 "Level-1 only"; 1417 } 1418 } 1419 case level-1-2 { 1420 leaf level-1-2 { 1421 type empty; 1422 description 1423 "Level-1 and Level-2"; 1424 } 1425 } 1426 } 1427 } 1428 } 1430 grouping isis-link-attributes { 1431 description 1432 "ISIS link scope attributes"; 1433 container isis-link-attributes { 1434 description 1435 "Containing link attributes"; 1436 leaf multi-topology-id { 1437 type uint8 { 1438 range "0..127"; 1439 } 1440 description 1441 "Multi topology ID"; 1442 } 1443 } 1444 } 1446 augment "/l3t:igp-node-event" { 1447 description 1448 "ISIS node event"; 1449 uses isis-topology-type; 1450 uses isis-node-attributes; 1451 } 1453 augment "/l3t:igp-link-event" { 1454 description 1455 "ISIS link event"; 1456 uses isis-topology-type; 1457 uses isis-link-attributes; 1458 } 1459 } 1460 1462 7. Security Considerations 1464 The transport protocol used for sending the topology data MUST 1465 support authentication and SHOULD support encryption. The data-model 1466 by itself does not create any security implications. 1468 8. Contributors 1470 The model presented in this paper was contributed to by more people 1471 than can be listed on the author list. Additional contributors 1472 include: 1474 o Ken Gray, Juniper Networks 1476 o Tom Nadeau, Brocade 1478 o Aleksandr Zhdankin, Cisco 1480 9. Acknowledgements 1482 We wish to acknowledge the helpful contributions, comments, and 1483 suggestions that were received from Ladislav Lhotka, Andy Bierman, 1484 Carlos Pignataro, Joel Halpern, Juergen Schoenwaelder, Alia Atlas, 1485 and Susan Hares. 1487 10. References 1489 10.1. Normative References 1491 [I-D.draft-ietf-i2rs-yang-network-topo] 1492 Clemm, A., Medved, J., Tkacik, T., Varga, R., Bahadur, N., 1493 Ananthakrishnan, H., and X. Liu, "A YANG Data Model for 1494 Network Topologies", I-D draft-ietf-i2rs-yang-network- 1495 topo-03, June 2016. 1497 [I-D.draft-ietf-netconf-restconf] 1498 Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF 1499 Protocol", I-D draft-ietf-netconf-restconf-13, April 2016. 1501 [I-D.draft-ietf-netmod-rfc6020bis] 1502 Bjorklund, M., "The YANG 1.1 Data Modeling Language", I-D 1503 draft-ietf-netmod-rfc6020bis-13, June 2016. 1505 [I-D.draft-ietf-netmod-yang-json] 1506 Lhotka, L., "JSON Encoding of Data Modeled with YANG", 1507 I-D draft-ietf-netmod-yang-json-10, March 2016. 1509 [RFC1195] Callon, R., "Use of OSI IS-IS for Routing in TCP/IP and 1510 Dual Environments", RFC 1195, December 1990. 1512 [RFC2178] Moy, J., "OSPF Version 2", RFC 2178, July 1997. 1514 [RFC6020] Bjorklund, M., "YANG - A Data Modeling Language for the 1515 Network Configuration Protocol (NETCONF)", RFC 6020, 1516 October 2010. 1518 [RFC6241] Enns, R., Bjorklund, M., Schoenwaelder, J., and A. 1519 Bierman, "Network Configuration Protocol (NETCONF)", 1520 RFC 6241, June 2011. 1522 [RFC6991] Schoenwaelder, J., "Common YANG Data Types", RFC 6991, 1523 July 2013. 1525 [RFC7223] Bjorklund, M., "A YANG Data Model for Interface 1526 Management", RFC 7223, May 2014. 1528 10.2. Informative References 1530 [I-D.draft-ietf-i2rs-usecase-reqs-summary] 1531 Hares, S. and M. Chen, "Summary of I2RS Use Case 1532 Requirements", I-D draft-ietf-i2rs-usecase-reqs-summary- 1533 02, March 2016. 1535 Authors' Addresses 1537 Alexander Clemm 1538 Cisco 1540 EMail: alex@cisco.com 1542 Jan Medved 1543 Cisco 1545 EMail: jmedved@cisco.com 1547 Robert Varga 1548 Pantheon Technologies SRO 1550 EMail: robert.varga@pantheon.sk 1552 Tony Tkacik 1553 Pantheon Technologies SRO 1555 EMail: tony.tkacik@pantheon.sk 1557 Xufeng Liu 1558 Kuatro Technologies 1560 EMail: xliu@kuatrotech.com 1562 Igor Bryskin 1563 Huawei 1565 EMail: Igor.Bryskin@huawei.com 1566 Aihua Guo 1567 Adva Optical 1569 EMail: aguo@advaoptical.com 1571 Hariharan Ananthakrishnan 1572 Packet Design 1574 EMail: hari@packetdesign.com 1576 Nitin Bahadur 1577 Bracket Computing 1579 EMail: nitin_bahadur@yahoo.com 1581 Vishnu Pavan Beeram 1582 Juniper Networks 1584 EMail: vbeeram@juniper.net