Network Working Group A. Lindem Internet-Draft Y. Qu Intended status: Standards Track Cisco Systems Expires: May 1, 2017 October 28, 2016 YANG Data Model for RIB Extensions draft-acee-rtgwg-yang-rib-extend-02.txt Abstract The Routing Information Base (RIB) is a list of routes and their corresponding administrative data and operational state. The document [ROUTING-CFG] defines the basic building blocks for RIB, and this model augments it to support repair paths and additional attributes for routes and next-hops (aka, paths). Status of This Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. 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 May 1, 2017. Copyright Notice Copyright (c) 2016 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 carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of Lindem & Qu Expires May 1, 2017 [Page 1] Internet-Draft YANG RIB Extensions October 2016 the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1.1. Requirements Notation . . . . . . . . . . . . . . . . . . 2 2. Design of the Model . . . . . . . . . . . . . . . . . . . . . 2 2.1. Static routes . . . . . . . . . . . . . . . . . . . . . . 3 2.2. Repair path . . . . . . . . . . . . . . . . . . . . . . . 3 3. RIB Model Tree . . . . . . . . . . . . . . . . . . . . . . . 3 4. RIB YANG Model . . . . . . . . . . . . . . . . . . . . . . . 5 5. Security Considerations . . . . . . . . . . . . . . . . . . . 9 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 9 7. References . . . . . . . . . . . . . . . . . . . . . . . . . 10 7.1. Normative References . . . . . . . . . . . . . . . . . . 10 7.2. Informative References . . . . . . . . . . . . . . . . . 10 Appendix A. Acknowledgments . . . . . . . . . . . . . . . . . . 10 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 11 1. Introduction This document defines a YANG, [YANG], data model which extends the generic data model for RIB by augmenting the ietf-routing model as defined in [ROUTING-CFG]. RIB is a collection of best routes from all routing protocols. Within a protocol routes are selected based on the metrics in use by that protocol, and the protocol install its best routes to RIB. RIB selects the best route by comparing the route preference (aka, administrative distance) of the associated protocol. The augmentations described herein extend the RIB to support repair paths route metrics, and administrative tags. 1.1. Requirements Notation The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC-KEYWORDS]. 2. Design of the Model The YANG definitions in this document augment the ietf-routing model defined in [ROUTING-CFG], which provides a basis for routing system data model development. Together with modules defined in [ROUTING-CFG], a generic RIB Yang model is defined to implement and monitor RIB. Lindem & Qu Expires May 1, 2017 [Page 2] Internet-Draft YANG RIB Extensions October 2016 The models in [ROUTING-CFG] also define the basic configuration and operational state for both IPv4 and IPv6 static routes and this document also provides augmentations for static routes to support more next-hop attributes. 2.1. Static routes Both Ipv4 and IPv6 static route configuration are defined in [ROUTING-CFG] with a multi-next-hop option. A static route/prefix can be configured to have multiple next-hops, each with their own tag and route preference. This model augments both IPv4 and IPv6 static route configuration with tag and route preference. 2.2. Next-Hop Repair path IP Fast Reroute repair paths can be pre-computed for route next-hops and installed in a RIB. For example, a routing protocol can install repair paths computed using the LFA (Loop-Free Alternative) computation. A repair path is augmented in RIB operation state for each path. 3. RIB Model Tree A simplified graphical representation of the augmentations described herein is included below. The meaning of the symbols in this diagrams is as follows: o Brackets "[" and "]" enclose list keys. o Curly braces "{" and "}" contain names of optional features that make the corresponding node conditional. o Abbreviations before data node names: "rw" means configuration (read-write), "ro" state data (read-only), "-x" RPC operations, and "-n" notifications. o Symbols after data node names: "?" means an optional node, "!" a container with presence, and "*" denotes a "list" or "leaf-list". o Parentheses enclose choice and case nodes, and case nodes are also marked with a colon (":"). o Ellipsis ("...") stands for contents of subtrees that are not shown. Lindem & Qu Expires May 1, 2017 [Page 3] Internet-Draft YANG RIB Extensions October 2016 module: ietf-rib-extension augment /rt:routing/rt:control-plane-protocols/rt:control-plane-protocol /rt:static-routes/v4ur:ipv4/v4ur:route/v4ur:next-hop /v4ur:next-hop-options/v4ur:simple-next-hop: +--rw preference? uint32 +--rw tag? uint32 augment /rt:routing/rt:control-plane-protocols/rt:control-plane-protocol /rt:static-routes/v4ur:ipv4/v4ur:route/v4ur:next-hop /v4ur:next-hop-options/v4ur:next-hop-list/v4ur:next-hop-list /v4ur:next-hop: +--rw preference? uint32 +--rw tag? uint32 augment /rt:routing/rt:control-plane-protocols/rt:control-plane-protocol /rt:static-routes/v6ur:ipv6/v6ur:route/v6ur:next-hop /v6ur:next-hop-options/v6ur:simple-next-hop: +--rw preference? uint32 +--rw tag? uint32 augment /rt:routing/rt:control-plane-protocols/rt:control-plane-protocol /rt:static-routes/v6ur:ipv6/v6ur:route/v6ur:next-hop /v6ur:next-hop-options/v6ur:next-hop-list /v6ur:next-hop-list/v6ur:next-hop: +--rw preference? uint32 +--rw tag? uint32 augment /rt:routing-state/rt:ribs/rt:rib/rt:routes/rt:route: +--ro metric? uint32 +--ro tag? uint32 augment /rt:routing-state/rt:ribs/rt:rib/rt:routes/rt:route /rt:next-hop/rt:next-hop-options/rt:simple-next-hop: +--ro repair-path +--ro interface? if:interface-ref +--ro address? inet:ip-address +--ro metric? uint32 augment /rt:routing-state/rt:ribs/rt:rib/rt:routes/rt:route /rt:next-hop/rt:next-hop-options/rt:special-next-hop: +--ro repair-path +--ro interface? if:interface-ref +--ro address? inet:ip-address +--ro metric? uint32 augment /rt:routing-state/rt:ribs/rt:rib/rt:routes/rt:route /rt:next-hop/rt:next-hop-options/rt:next-hop-list /rt:next-hop-list/rt:next-hop: +--ro repair-path +--ro interface? if:interface-ref +--ro address? inet:ip-address +--ro metric? uint32 Lindem & Qu Expires May 1, 2017 [Page 4] Internet-Draft YANG RIB Extensions October 2016 4. RIB YANG Model file "ietf-rib-extension@2015-10-28.yang" module ietf-rib-extension { namespace "urn:ietf:params:xml:ns:yang:ietf-rib-extension"; prefix rib; import ietf-inet-types { prefix "inet"; } import ietf-interfaces { prefix "if"; } import ietf-routing { prefix "rt"; } import ietf-ipv4-unicast-routing { prefix "v4ur"; } import ietf-ipv6-unicast-routing { prefix "v6ur"; } organization "Cisco Systems 170 West Tasman Drive San Jose, CA 95134-1706 USA"; contact "Acee Lindem - acee@cisco.com Yingzhen QU - yiqu@cisco.com"; description "This YANG module extends the generic data model for RIB by augmenting the ietf-netmod-routing-cfg model. It is intended that the module will be extended by vendors to define vendor-specific RIB parameters. "; revision 2016-10-28 { description "* Update to new routing-cfg model. "; Lindem & Qu Expires May 1, 2017 [Page 5] Internet-Draft YANG RIB Extensions October 2016 reference "RFC XXXX: A YANG Data Model for RIB Extensions."; } revision 2016-03-15 { description "* Update to new routing-cfg model. * Added MPLS label forwarding table. "; reference "RFC XXXX: A YANG Data Model for RIB Extensions."; } revision 2015-10-16 { description "Initial revision."; reference "RFC XXXX: A YANG Data Model for RIB Extensions."; } /* Groupings */ grouping next-hop { description "Next-hop grouping"; leaf interface { type if:interface-ref; description "Outgoing interface"; } leaf address { type inet:ip-address; description "IPv4 or IPv6 Address of the next-hop"; } } grouping attributes { description "Common attributes applicable to all paths"; leaf metric { type uint32; description "Route metric"; } leaf tag { type uint32; description "Route tag"; } } Lindem & Qu Expires May 1, 2017 [Page 6] Internet-Draft YANG RIB Extensions October 2016 grouping path-attribute { description "Path attribute grouping"; container repair-path { uses next-hop; leaf metric { type uint32; description "Route metric"; } description "IP Fast ReRoute (IPFRR) repair path"; } } augment "/rt:routing/rt:control-plane-protocols/" + "rt:control-plane-protocol/rt:static-routes/v4ur:ipv4/" + "v4ur:route/v4ur:next-hop/v4ur:next-hop-options/" + "v4ur:simple-next-hop" { description "Augment 'simple-next-hop' case in IPv4 unicast route."; leaf preference { type uint32; default "1"; description "Route preference - Used to select among multiple static routes with a lower preference next-hop preferred and equal preference paths yielding Equal Cost Multi-Path (ECMP)."; } leaf tag { type uint32; default "0"; description "Route tag"; } } augment "/rt:routing/rt:control-plane-protocols/" + "rt:control-plane-protocol/rt:static-routes/v4ur:ipv4/" + "v4ur:route/v4ur:next-hop/v4ur:next-hop-options/" + "v4ur:next-hop-list/v4ur:next-hop-list/v4ur:next-hop" { description "Augment static route configuration 'next-hop-list'."; leaf preference { type uint32; default "1"; description "Route preference - Used to select among multiple static routes with a lower preference next-hop preferred and equal preference paths yielding Equal Cost Multi-Path (ECMP)."; } leaf tag { type uint32; Lindem & Qu Expires May 1, 2017 [Page 7] Internet-Draft YANG RIB Extensions October 2016 default "0"; description "Route tag"; } } augment "/rt:routing/rt:control-plane-protocols/" + "rt:control-plane-protocol/rt:static-routes/v6ur:ipv6/" + "v6ur:route/v6ur:next-hop/v6ur:next-hop-options/" + "v6ur:simple-next-hop" { description "Augment 'simple-next-hop' case in IPv6 unicast route."; leaf preference { type uint32; default "1"; description "Route preference - Used to select among multiple static routes with a lower preference next-hop preferred and equal preference paths yielding Equal Cost Multi-Path (ECMP)."; } leaf tag { type uint32; default "0"; description "Route tag"; } } augment "/rt:routing/rt:control-plane-protocols/" + "rt:control-plane-protocol/rt:static-routes/v6ur:ipv6/" + "v6ur:route/v6ur:next-hop/v6ur:next-hop-options/" + "v6ur:next-hop-list/v6ur:next-hop-list/v6ur:next-hop" { description "Augment static route configuration 'next-hop-list'."; leaf preference { type uint32; default "1"; description "Route preference - Used to select among multiple static routes with a lower preference next-hop preferred and equal preference paths yielding Equal Cost Multi-Path (ECMP)."; } leaf tag { type uint32; default "0"; description "Route tag"; } } augment "/rt:routing-state/rt:ribs/rt:rib/" + "rt:routes/rt:route" { description Lindem & Qu Expires May 1, 2017 [Page 8] Internet-Draft YANG RIB Extensions October 2016 "Augment a route in RIB with tag."; uses attributes; } augment "/rt:routing-state/rt:ribs/rt:rib/" + "rt:routes/rt:route/rt:next-hop/rt:next-hop-options/" + "rt:simple-next-hop" { description "Add more parameters to a path."; uses path-attribute; } augment "/rt:routing-state/rt:ribs/rt:rib/" + "rt:routes/rt:route/rt:next-hop/rt:next-hop-options/" + "rt:special-next-hop" { description "Add more parameters to a path."; uses path-attribute; } augment "/rt:routing-state/rt:ribs/rt:rib/" + "rt:routes/rt:route/rt:next-hop/rt:next-hop-options/" + "rt:next-hop-list/rt:next-hop-list/rt:next-hop" { description "This case augments the 'next-hop-options' in the routing model."; uses path-attribute; } } 5. Security Considerations The YANG model augmentations defined herein do not introduce any security issues other than those already discussed in [ROUTING-CFG], and [NETCONF]. If confidentiality is desired, the underlying NETCONF communication should be utilized as described in [NETCONF-SSH]. 6. IANA Considerations This document registers a URI in the IETF XML registry [XML-REGISTRY]. Following the format in RFC 3688, the following registration is requested to be made: URI: urn:ietf:params:xml:ns:yang:ietf-rib Lindem & Qu Expires May 1, 2017 [Page 9] Internet-Draft YANG RIB Extensions October 2016 Registrant Contact: The IESG. XML: N/A, the requested URI is an XML namespace. This document registers a YANG module in the YANG Module Names registry [YANG]. name: ietf-acl namespace: urn:ietf:params:xml:ns:yang:ietf-rib prefix: ietf-rib reference: RFC XXXX 7. References 7.1. Normative References [RFC-KEYWORDS] Bradner, S., "Key words for use in RFC's to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [ROUTING-CFG] Lhothka, L. and A. Lindem, "A YANG Data Model for Routing Management", draft-ietf-netmod-routing-cfg-24.txt (work in progress), October 2016. [YANG] Bjorklund, M., "YANG - A Data Modeling Language for the Network Configuration Protocol (NETCONF)", RFC 6020, October 2010. 7.2. Informative References [NETCONF] Enns, R., Bjorklund, M., Schoenwaelder, J., and A. Bierman, "Network Configuration Protocol (NETCONF)", RFC 6241, June 2011. [NETCONF-SSH] Wasserman, M., "Using NETCONF Protocol over Secure Shell (SSH)", RFC 6242, June 2011. [XML-REGISTRY] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688, January 2004. Appendix A. Acknowledgments The RFC text was produced using Marshall Rose's xml2rfc tool. The authors wish to thank Les Ginsberg, Krishna Deevi and Suyoung Yoon for their helpful comments and suggestions. Lindem & Qu Expires May 1, 2017 [Page 10] Internet-Draft YANG RIB Extensions October 2016 Authors' Addresses Acee Lindem Cisco Systems 301 Midenhall Way Cary, NC 27513 USA Email: acee@cisco.com Yingzhen Qu Cisco Systems 170 West Tasman Drive San Jose, CA 95134 USA Email: yiqu@cisco.com Lindem & Qu Expires May 1, 2017 [Page 11]