--- 1/draft-ietf-i2rs-yang-l3-topology-09.txt 2017-07-02 02:13:09.465018122 -0700 +++ 2/draft-ietf-i2rs-yang-l3-topology-10.txt 2017-07-02 02:13:09.529019640 -0700 @@ -1,27 +1,27 @@ Network Working Group A. Clemm Internet-Draft Huawei Intended status: Standards Track J. Medved -Expires: December 28, 2017 Cisco +Expires: January 3, 2018 Cisco R. Varga Pantheon Technologies SRO X. Liu Ericsson H. Ananthakrishnan Packet Design N. Bahadur Bracket Computing - June 26, 2017 + July 2, 2017 A YANG Data Model for Layer 3 Topologies - draft-ietf-i2rs-yang-l3-topology-09.txt + draft-ietf-i2rs-yang-l3-topology-10.txt Abstract This document defines a YANG data model for layer 3 network topologies. Status of This Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. @@ -29,21 +29,21 @@ Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at http://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." - This Internet-Draft will expire on December 28, 2017. + This Internet-Draft will expire on January 3, 2018. Copyright Notice Copyright (c) 2017 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents @@ -68,21 +68,23 @@ 6.2.1. Model Overview . . . . . . . . . . . . . . . . . . . 22 6.2.2. IS-IS Topology YANG Module . . . . . . . . . . . . . 23 7. Interactions with Other YANG Modules . . . . . . . . . . . . 28 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 28 9. Security Considerations . . . . . . . . . . . . . . . . . . . 29 10. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 29 11. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 30 12. References . . . . . . . . . . . . . . . . . . . . . . . . . 30 12.1. Normative References . . . . . . . . . . . . . . . . . . 30 12.2. Informative References . . . . . . . . . . . . . . . . . 31 - Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 31 + Appendix A. Companion YANG model for non-NMDA compliant + implementations . . . . . . . . . . . . . . . . . . 32 + Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 36 1. Introduction This document introduces a YANG [RFC7950] [RFC6991] data model for Layer 3 network topologies, specifically Layer 3 Unicast. The model allows an application to have a holistic view of the topology of a Layer 3 network, all contained in a single conceptual YANG datastore. The data model builds on top of, and augments, the data model for network topologies defined in [I-D.draft-ietf-i2rs-yang-network-topo]. @@ -132,28 +134,30 @@ as instantiated YANG data. Data tree: An instantiated tree of data modeled with YANG, in which individual data items are represented by data nodes which are arranged in hierarchical manner. Data subtree: An instantiated data node and the data nodes that are hierarchically contained within it. HTTP: Hyper-Text Transfer Protocol - IGP: Interior Gateway Protocol + IS-IS: Intermediate System to Intermediate System protocol LSP: Label Switched Path NETCONF: Network Configuration Protocol + NMDA: Network Management Datastore Architecture + OSPF: Open Shortest Path First, a link state routing protocol URI: Uniform Resource Identifier ReST: Representational State Transfer, a style of stateless interface and protocol that is generally carried over HTTP SRLG: Shared Risk Link Group TED: Traffic Engineering Database @@ -190,27 +194,38 @@ Figure 1: Overall model structure YANG modules "ietf-network" and "ietf-network-topology" collectively define the basic network topology model. YANG module "ietf-l3- unicast-topology" augments those models with additional definitions needed to represent Layer 3 Unicast topologies. This module in turn can be augmented by YANG modules with additional definitions for specific types of Layer 3 Unicast topologies, such as OSPF and for IS-IS topologies. + The YANG modules ietf-network and ietf-network are designed to be + used in conjunction with implementations that support the Network + Management Datastore Architecture (NMDA) defined in + [I-D.draft-ietf-netmod-revised-datastores]. Accordingly, the same is + true for the YANG modules that augment it. In order to allow + implementations to use the model even in cases when NMDA is not + supported, companion YANG modules (that SHOULD NOT be supported by + implementations that support NMDA) are defined in an Appendix, see + Appendix A. + 4. Layer 3 Unicast Topology Model Overview The Layer 3 Unicast topology model is defined by YANG module "ietf- l3-unicast-topology" and depicted in the following diagram. Brackets enclose list keys, "rw" means configuration, "ro" operational state data, "?" designates optional nodes, "*" designates nodes that can have multiple instances. Parantheses enclose choice and case nodes. + The prefix "nd:" refers to the YANG module for networks; the prefix "lnk:" refers to the YANG module for network topology. In the interest of brevity, notifications are not depicted. module: ietf-l3-unicast-topology augment /nd:networks/nd:network/nd:network-types: +--rw l3-unicast-topology! augment /nd:networks/nd:network: +--rw l3-topology-attributes +--rw name? string @@ -273,21 +288,21 @@ type of event, the topology from which it originated, and the affected node, or link, or prefix, or termination point. In addition, as a convenience to applications, additional data of the affected node, or link, or termination point (respectively) is included. While this makes notifications larger in volume than they would need to be, it avoids the need for subsequent retrieval of context information, which also might have changed in the meantime. 5. Layer 3 Unicast Topology YANG Module - file "ietf-l3-unicast-topology@2017-06-26.yang" + file "ietf-l3-unicast-topology@2017-07-02.yang" module ietf-l3-unicast-topology { yang-version 1.1; namespace "urn:ietf:params:xml:ns:yang:ietf-l3-unicast-topology"; prefix "l3t"; import ietf-network { prefix "nd"; } import ietf-network-topology { prefix "lnk"; @@ -322,39 +336,38 @@ topologies. Copyright (c) 2017 IETF Trust and the persons identified as authors of the code. All rights reserved. Redistribution and use in source and binary forms, with or without modification, is permitted pursuant to, and subject to the license terms contained in, the Simplified BSD License set forth in Section 4.c of the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info). This version of this YANG module is part of - draft-ietf-i2rs-yang-l3-topology-09; + draft-ietf-i2rs-yang-l3-topology-10; see the RFC itself for full legal notices. NOTE TO RFC EDITOR: Please replace above reference to - draft-ietf-i2rs-yang-l3-topology-09 with RFC + draft-ietf-i2rs-yang-l3-topology-10 with RFC number when published (i.e. RFC xxxx)."; - revision "2017-06-26" { + revision "2017-07-02" { description "Initial revision. NOTE TO RFC EDITOR: Please replace the following reference - to draft-ietf-i2rs-yang-l3-topology-09 with + to draft-ietf-i2rs-yang-l3-topology-10 with RFC number when published (i.e. RFC xxxx)."; reference - "draft-ietf-i2rs-yang-l3-topology-09"; + "draft-ietf-i2rs-yang-l3-topology-10"; } identity flag-identity { description "Base type for flags"; } - typedef l3-event-type { type enumeration { enum "add" { description "An Layer 3 node or link or prefix or termination-point has been added"; } enum "remove" { description "An Layer 3 node or link or prefix or termination-point has @@ -738,21 +750,21 @@ OSPF routers or interfaces. 6.1.2. OSPF Topology YANG Module The OSPF Topology YANG Module is specified below. As mentioned, the module is intended as an example for how the Layer 3 Unicast topology model can be extended to cover OSFP topologies, but it is not normative. Accordingly, the module is not delimited with CODE BEGINS and CODE ENDS tags. - file "example-ietf-ospf-topology@2017-06-26.yang" + file "example-ietf-ospf-topology@2017-07-02.yang" module example-ietf-ospf-topology { yang-version 1.1; namespace "urn:ietf:params:xml:ns:yang:example-ietf-ospf-topology"; prefix "ospft"; import ietf-yang-types { prefix "yang"; } import ietf-network { prefix "nd"; } @@ -788,33 +800,33 @@ "This module defines a model for OSPF network topologies. Copyright (c) 2017 IETF Trust and the persons identified as authors of the code. All rights reserved. Redistribution and use in source and binary forms, with or without modification, is permitted pursuant to, and subject to the license terms contained in, the Simplified BSD License set forth in Section 4.c of the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info). This version of this YANG module is part of - draft-ietf-i2rs-yang-l3-topology-09; + draft-ietf-i2rs-yang-l3-topology-10; see the RFC itself for full legal notices. NOTE TO RFC EDITOR: Please replace above reference to - draft-ietf-i2rs-yang-l3-topology-09 with RFC + draft-ietf-i2rs-yang-l3-topology-10 with RFC number when published (i.e. RFC xxxx)."; - revision "2017-06-26" { + revision "2017-07-02" { description "Initial revision. NOTE TO RFC EDITOR: Please replace the following reference - to draft-ietf-i2rs-yang-l3-topology-09 with + to draft-ietf-i2rs-yang-l3-topology-10 with RFC number when published (i.e. RFC xxxx)."; reference - "draft-ietf-i2rs-yang-l3-topology-09"; + "draft-ietf-i2rs-yang-l3-topology-10"; } typedef area-id-type { type yang:dotted-quad; description "Area ID type."; } grouping ospf-topology-type { description "Identifies the OSPF topology type."; container ospf { @@ -1024,21 +1036,21 @@ configure IS-IS routers or interfaces. 6.2.2. IS-IS Topology YANG Module The IS-IS Topology YANG Module is specified as follows. As mentioned, the module is intended as an example for how the Layer 3 Unicast topology model can be extended to cover IS-IS topologies, but it is not normative. Accordingly, the module is not delimited with CODE BEGINS and CODE ENDS tags. - file "example-ietf-isis-topology@2017-06-26.yang" + file "example-ietf-isis-topology@2017-07-02.yang" module example-ietf-isis-topology { yang-version 1.1; namespace "urn:ietf:params:xml:ns:yang:example-ietf-isis-topology"; prefix "isist"; import ietf-network { prefix "nd"; } import ietf-network-topology { prefix "lnk"; } @@ -1070,33 +1082,33 @@ "This module defines a model for IS-IS network topologies. Copyright (c) 2017 IETF Trust and the persons identified as authors of the code. All rights reserved. Redistribution and use in source and binary forms, with or without modification, is permitted pursuant to, and subject to the license terms contained in, the Simplified BSD License set forth in Section 4.c of the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info). This version of this YANG module is part of - draft-ietf-i2rs-yang-l3-topology-08; + draft-ietf-i2rs-yang-l3-topology-10; see the RFC itself for full legal notices. NOTE TO RFC EDITOR: Please replace above reference to - draft-ietf-i2rs-yang-l3-topology-08 with RFC + draft-ietf-i2rs-yang-l3-topology-10 with RFC number when published (i.e. RFC xxxx)."; - revision "2017-06-26" { + revision "2017-07-02" { description "Initial revision. NOTE TO RFC EDITOR: Please replace the following reference - to draft-ietf-i2rs-yang-l3-topology-08 with + to draft-ietf-i2rs-yang-l3-topology-10 with RFC number when published (i.e. RFC xxxx)."; reference - draft-ietf-i2rs-yang-l3-topology-08; + draft-ietf-i2rs-yang-l3-topology-10; } typedef iso-pseudonode-id { type string { pattern '[0-9a-fA-F]{2}'; } description "ISO pseudonode id for broadcast network."; } typedef area-address{ @@ -1275,34 +1287,43 @@ The model obeys the requirements for the ephemeral state found in the document [I-D.draft-ietf-i2rs-ephemeral-state]. For ephemeral topology data that is server provided, the process tasked with maintaining topology information will load information from the routing process (such as OSPF) into the data model without relying on a configuration datastore. 8. IANA Considerations - This document registers the following namespace URI in the "IETF XML + This document registers the following namespace URIs in the "IETF XML Registry" [RFC3688]: URI: urn:ietf:params:xml:ns:yang:ietf-l3-unicast-topology Registrant Contact: The IESG. XML: N/A; the requested URI is an XML namespace. - This document registers the following YANG module in the "YANG Module - Names" registry [RFC6020]: + URI: urn:ietf:params:xml:ns:yang:ietf-l3-unicast-topology-state + Registrant Contact: The IESG. + XML: N/A; the requested URI is an XML namespace. + + This document registers the following YANG modules in the "YANG + Module Names" registry [RFC6020]: Name: ietf-l3-unicast-topology Namespace: urn:ietf:params:xml:ns:yang:ietf-l3-unicast-topology Prefix: l3t - Reference: draft-ietf-i2rs-yang-l3-topology-08.txt (RFC form) + Reference: draft-ietf-i2rs-yang-l3-topology-10.txt (RFC form) + + Name: ietf-l3-unicast-topology-state + Namespace: urn:ietf:params:xml:ns:yang:ietf-l3-unicast-topology-state + Prefix: l3t-s + Reference: draft-ietf-i2rs-yang-l3-topology-10.txt (RFC form) 9. Security Considerations The YANG module defined in this memo is designed to be accessed via the NETCONF protocol [RFC6241]. The lowest NETCONF layer is the secure transport layer, and the mandatory-to-implement secure transport is Secure Shell (SSH) [RFC6242]. The NETCONF access control model [RFC6536] provides the means to restrict access for particular NETCONF users to a pre-configured subset of all available NETCONF protocol operations and content. @@ -1347,21 +1368,27 @@ Susan Hares, Benoit Claise, and Carl Moberg. 12. References 12.1. Normative References [I-D.draft-ietf-i2rs-yang-network-topo] Clemm, A., Medved, J., Varga, R., Bahadur, N., Ananthakrishnan, H., and X. Liu, "A YANG Data Model for Network Topologies", I-D draft-ietf-i2rs-yang-network- - topo-13, June 2017. + topo-14, June 2017. + + [I-D.draft-ietf-netmod-revised-datastores] + Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K., + and R. Wilton, "A Revised Conceptual Model for YANG + Datastores", I-D draft-ietf-netmod-revised-datastores-02, + May 2017. [RFC1195] Callon, R., "Use of OSI IS-IS for Routing in TCP/IP and Dual Environments", RFC 1195, December 1990. [RFC2328] Moy, J., "OSPF Version 2", RFC 2328, April 1998. [RFC2863] McCloghrie, K. and F. Kastenholz, "The Interfaces Group MIB", RFC 2863, June 2000. [RFC3688] Mealling, M., "The IETF XML Registry", RFC 3688, January @@ -1409,20 +1436,233 @@ Liu, X., Bryskin, I., Beeram, V., Saad, T., Shah, H., and O. Gonzalez De Dios, "YANG Data Model for TE Topologies", I-D draft-ietf-teas-yang-te-topo-09, June 2017. [RFC7223] Bjorklund, M., "A YANG Data Model for Routing Management", RFC 7223, May 2014. [RFC8022] Lhotka, L. and A. Lindem, "A YANG Data Model for Routing Management", RFC 8022, November 2016. +Appendix A. Companion YANG model for non-NMDA compliant implementations + + The YANG module ietf-l3-unicast-topology defined in this document + augments two modules, ietf-network and ietf-network-topology, that + are designed to be used in conjunction with implementations that + support the Network Management Datastore Architecture (NMDA) defined + in [I-D.draft-ietf-netmod-revised-datastores]. In order to allow + implementations to use the model even in cases when NMDA is not + supported, a set of companion modules have been defined that + represent a state model of networks and network topologies, ietf- + network-state and ietf-network-topology-state, respectively. + + In order to be able to use the model for layer 3 topologies defined + in this in this document in conjunction with non-NMDA compliant + implementations, a corresponding companion module needs to be + introduced as well. This companion module, ietf-l3-unicast-topology- + state, mirrors ietf-l3-unicast-topology. However, the module + augments ietf-network-state and ietf-network-topology-state (instead + of ietf-network and ietf-network-state) and all of its data nodes are + non-configurable. + + Similar considerations apply for any modules that augment ietf-l3- + unicast-topology, such as the example modules defined earlier, + example-ietf-ospf-topology and example-ietf-isis-topology. For non- + NMDA compliant implementations, companion modules will need to be + introduced that represent state information and are non-configurable, + augmenting ietf-l3-unicast-topology-state instead of ietf-l3-unicast- + topology. Because they served as examples only, companion modules + for those examples are not given. + + Like ietf-network-state and ietf-network-topology-state, ietf-l3- + unicast-topology SHOULD NOT be supported by implementations that + support NMDA. It is for this reason that the module is defined in + the Appendix. + + The definition of the module follows below. As the structure of the + module mirrors that of its underlying module, the YANG tree is not + depicted separately. + + file "ietf-l3-unicast-topology-state@2017-07-02.yang" + module ietf-l3-unicast-topology-state { + yang-version 1.1; + namespace + "urn:ietf:params:xml:ns:yang:ietf-l3-unicast-topology-state"; + prefix "l3t-s"; + import ietf-network-state { + prefix "nd-s"; + } + import ietf-network-topology-state { + prefix "lnk-s"; + } + import ietf-l3-unicast-topology { + prefix "l3t"; + } + organization + "IETF I2RS (Interface to the Routing System) Working Group"; + contact + "WG Web: + WG List: + WG Chair: Susan Hares + + WG Chair: Russ White + + Editor: Alexander Clemm + + Editor: Jan Medved + + Editor: Robert Varga + + Editor: Xufeng Liu + + Editor: Nitin Bahadur + + Editor: Hariharan Ananthakrishnan + "; + description + "This module defines a model for Layer 3 Unicast topology + state, representing topology that is either learned, or topology + that results from applying topology that has been configured per + the ietf-l3-unicast-topology model, mirroring the corresponding + data nodes in this model. + + The model mirrors ietf-l3-unicast-topology, but contains only + read-only state data. The model is not needed when the + underlying implementation infrastructure supports the Network + Management Datastore Architecture (NMDA). + + Copyright (c) 2017 IETF Trust and the persons identified as + authors of the code. All rights reserved. + Redistribution and use in source and binary forms, with or + without modification, is permitted pursuant to, and subject + to the license terms contained in, the Simplified BSD License + set forth in Section 4.c of the IETF Trust's Legal Provisions + Relating to IETF Documents + (http://trustee.ietf.org/license-info). + This version of this YANG module is part of + draft-ietf-i2rs-yang-l3-topology-10; + see the RFC itself for full legal notices. + NOTE TO RFC EDITOR: Please replace above reference to + draft-ietf-i2rs-yang-l3-topology-10 with RFC + number when published (i.e. RFC xxxx)."; + revision "2017-07-02" { + description + "Initial revision. + NOTE TO RFC EDITOR: Please replace the following reference + to draft-ietf-i2rs-yang-l3-topology-10 with + RFC number when published (i.e. RFC xxxx)."; + reference + "draft-ietf-i2rs-yang-l3-topology-10"; + } + + augment "/nd-s:networks/nd-s:network/nd-s:network-types" { + description + "Introduce new network type for L3 unicast topology"; + uses l3t:l3-unicast-topology-type; + } + augment "/nd-s:networks/nd-s:network" { + when "nd-s:network-types/l3-unicast-topology" { + description + "Augmentation parameters apply only for networks with + L3 unicast topology"; + } + description + "L3 unicast for the network as a whole"; + uses l3t:l3-topology-attributes; + } + augment "/nd-s:networks/nd-s:network/nd-s:node" { + when "../nd-s:network-types/l3-unicast-topology" { + description + "Augmentation parameters apply only for networks with + L3 unicast topology"; + } + description + "L3 unicast node level attributes "; + uses l3t:l3-node-attributes; + } + augment "/nd-s:networks/nd-s:network/lnk-s:link" { + when "../nd-s:network-types/l3-unicast-topology" { + description + "Augmentation parameters apply only for networks with + L3 unicast topology"; + } + description + "Augment topology link attributes"; + + uses l3t:l3-link-attributes; + } + augment "/nd-s:networks/nd-s:network/nd-s:node/" + +"lnk-s:termination-point" { + when "../../nd-s:network-types/l3-unicast-topology" { + description + "Augmentation parameters apply only for networks with + L3 unicast topology"; + } + description "Augment topology termination point configuration"; + uses l3t:l3-termination-point-attributes; + } + notification l3-node-event { + description + "Notification event for L3 node"; + leaf l3-event-type { + type l3t:l3-event-type; + description + "Event type"; + } + uses nd-s:node-ref; + uses l3t:l3-unicast-topology-type; + uses l3t:l3-node-attributes; + } + notification l3-link-event { + description + "Notification event for L3 link"; + leaf l3-event-type { + type l3t:l3-event-type; + description + "Event type"; + } + uses lnk-s:link-ref; + uses l3t:l3-unicast-topology-type; + uses l3t:l3-link-attributes; + } + notification l3-prefix-event { + description + "Notification event for L3 prefix"; + leaf l3-event-type { + type l3t:l3-event-type; + description + "Event type"; + } + uses nd-s:node-ref; + uses l3t:l3-unicast-topology-type; + container prefix { + description + "Containing L3 prefix attributes"; + uses l3t:l3-prefix-attributes; + } + } + notification termination-point-event { + description + "Notification event for L3 termination point"; + leaf l3-event-type { + type l3t:l3-event-type; + description + "Event type"; + } + uses lnk-s:tp-ref; + uses l3t:l3-unicast-topology-type; + uses l3t:l3-termination-point-attributes; + } + } + + + Authors' Addresses Alexander Clemm Huawei EMail: ludwig@clemm.org Jan Medved Cisco