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Keywords: configuration, IPv6 Router Advertisements, NETCONF, RESTCONF, YANG, Routing, RIB

Internet Engineering Task Force (IETF) A. Lindem
Request for Comments: 9403 LabN Consulting, L.L.C.
Category: Standards Track Y. Qu
ISSN: 2070-1721 Futurewei Technologies
November 2023
A YANG Data Model for RIB Extensions
Abstract
A Routing Information Base (RIB) is a list of routes and their
corresponding administrative data and operational state.
RFC 8349 defines the basic building blocks for the RIB data model,
and this model augments it to support multiple next hops (aka paths)
for each route as well as additional attributes.
Status of This Memo
This is an Internet Standards Track document.
This document is a product of the Internet Engineering Task Force
(IETF). It represents the consensus of the IETF community. It has
received public review and has been approved for publication by the
Internet Engineering Steering Group (IESG). Further information on
Internet Standards is available in Section 2 of RFC 7841.
Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
https://www.rfc-editor.org/info/rfc9403.
Copyright Notice
Copyright (c) 2023 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
(https://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 Revised BSD License text as described in Section 4.e of the
Trust Legal Provisions and are provided without warranty as described
in the Revised BSD License.
Table of Contents
1. Introduction
2. Terminology and Notation
2.1. Tree Diagrams
2.2. Prefixes in Data Node Names
3. Design of the Model
3.1. Tags and Preferences
3.2. Repair Path
4. RIB Model Tree
5. RIB Extension YANG Module
6. Security Considerations
7. IANA Considerations
8. References
8.1. Normative References
8.2. Informative References
Appendix A. Combined Tree Diagram
Appendix B. ietf-rib-extension.yang example
Acknowledgments
Authors' Addresses
1. Introduction
This document defines a YANG data model [RFC7950] that extends the
RIB data model defined in the ietf-routing YANG module [RFC8349] with
more route attributes.
A RIB is a collection of routes with attributes controlled and
manipulated by control plane protocols. Each RIB contains only
routes of one address family [RFC8349]. Within a protocol, routes
are selected based on the metrics in use by that protocol, and the
protocol installs the routes to the RIB. The RIB selects the
preferred or active route by comparing the route preference (aka
administrative distance) of the candidate routes installed by
different protocols.
The module defined in this document extends the RIB to support more
route attributes, such as multiple next hops, route metrics, and
administrative tags.
The YANG modules defined and discussed in this document conform to
the Network Management Datastore Architecture (NMDA) [RFC8342].
2. Terminology and Notation
The following terms are defined in [RFC8342]:
* configuration
* system state
* operational state
The following terms are defined in [RFC7950]:
* action
* augment
* container
* container with presence
* data model
* data node
* leaf
* list
* mandatory node
* module
* schema tree
The following term is defined in [RFC8349], Section 5.2:
* RIB
2.1. Tree Diagrams
Tree diagrams used in this document follow the notation defined in
[RFC8340].
2.2. Prefixes in Data Node Names
In this document, names of data nodes, actions, and other data model
objects are often used without a prefix, as long as it is clear from
the context in which YANG module each name is defined. Otherwise,
names are prefixed using the standard prefix associated with the
corresponding YANG module, as shown in Table 1.
+========+===========================+===========+
| Prefix | YANG Module | Reference |
+========+===========================+===========+
| if | ietf-interfaces | [RFC8343] |
+--------+---------------------------+-----------+
| rt | ietf-routing | [RFC8349] |
+--------+---------------------------+-----------+
| v4ur | ietf-ipv4-unicast-routing | [RFC8349] |
+--------+---------------------------+-----------+
| v6ur | ietf-ipv6-unicast-routing | [RFC8349] |
+--------+---------------------------+-----------+
| inet | ietf-inet-types | [RFC6991] |
+--------+---------------------------+-----------+
| ospf | ietf-ospf | [RFC9129] |
+--------+---------------------------+-----------+
| isis | ietf-isis | [RFC9130] |
+--------+---------------------------+-----------+
Table 1: Prefixes and Corresponding YANG Modules
3. Design of the Model
The YANG module defined in this document augments the ietf-routing,
ietf-ipv4-unicast-routing, and ietf-ipv6-unicast-routing YANG modules
defined in [RFC8349], which provide a basis for routing system data
model development. Together with the ietf-routing YANG module and
other YANG modules defined in [RFC8349], a generic RIB YANG data
model is defined herein to implement and monitor a RIB.
The modules in [RFC8349] also define the basic configuration and
operational state for both IPv4 and IPv6 static routes. This
document provides augmentations for static routes to support multiple
next hops and more next-hop attributes.
3.1. Tags and Preferences
Individual route tags are supported at both the route and next-hop
level. A preference per next hop is also supported for selection of
the most preferred reachable static route.
The following tree snapshot shows tag and preference entries that
augment static IPv4 unicast route and IPv6 unicast route next hops.
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/rt:ribs/rt:rib/rt:routes/rt:route:
+--ro metric? uint32
+--ro tag* uint32
+--ro application-tag? uint32
3.2. Repair Path
The IP Fast Reroute (IPFRR) calculation by routing protocol
precomputes repair paths [RFC5714], and the repair paths are
installed in the RIB.
Each route next hop in the RIB is augmented with a repair path and is
shown in the following tree snapshot.
augment /rt:routing/rt:ribs/rt:rib/rt:routes/rt:route
/rt:next-hop/rt:next-hop-options/rt:simple-next-hop:
+--ro repair-path
+--ro outgoing-interface? if:interface-state-ref
+--ro next-hop-address? inet:ip-address-no-zone
+--ro metric? uint32
augment /rt:routing/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 outgoing-interface? if:interface-state-ref
+--ro next-hop-address? inet:ip-address-no-zone
+--ro metric? uint32
4. RIB Model Tree
The ietf-routing.yang tree with the augmentations herein is included
in Appendix A. The meanings of the symbols can be found in
[RFC8340].
5. RIB Extension YANG Module
This YANG module references [RFC6991], [RFC8343], [RFC8349],
[RFC9129], [RFC9130], and [RFC5714].
<CODE BEGINS> file "ietf-rib-extension@2023-11-20.yang"
module ietf-rib-extension {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-rib-extension";
prefix rib-ext;
import ietf-inet-types {
prefix inet;
reference
"RFC 6991: Common YANG Data Types";
}
import ietf-interfaces {
prefix if;
reference
"RFC 8343: A YANG Data Model for Interface
Management";
}
import ietf-routing {
prefix rt;
reference
"RFC 8349: A YANG Data Model for Routing
Management (NMDA Version)";
}
import ietf-ipv4-unicast-routing {
prefix v4ur;
reference
"RFC 8349: A YANG Data Model for Routing
Management (NMDA Version)";
}
import ietf-ipv6-unicast-routing {
prefix v6ur;
reference
"RFC 8349: A YANG Data Model for Routing
Management (NMDA Version)";
}
import ietf-ospf {
prefix ospf;
reference "RFC 9129: YANG Data Model for the OSPF Protocol";
}
import ietf-isis {
prefix isis;
reference "RFC 9130: YANG Data Model for the IS-IS Protocol";
}
organization
"IETF RTGWG (Routing Area Working Group)";
contact
"WG Web: <https://datatracker.ietf.org/wg/rtgwg/>
WG List: <mailto:rtgwg@ietf.org>
Author: Acee Lindem
<mailto:acee.ietf@gmail.com>
Author: Yingzhen Qu
<mailto:yingzhen.qu@futurewei.com>";
description
"This YANG module extends the RIB defined in the ietf-routing
YANG module with additional route attributes.
This YANG module conforms to the Network Management
Datastore Architecture (NMDA) as described in RFC 8342.
Copyright (c) 2023 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 Revised BSD License set
forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
(https://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC 9403; see the
RFC itself for full legal notices.";
revision 2023-11-20 {
description
"Initial version.";
reference
"RFC 9403: A YANG Data Model for RIB Extensions";
}
/* Groupings */
grouping rib-statistics {
description
"Statistics grouping used for RIB augmentation.";
container statistics {
config false;
description
"Container for RIB statistics.";
leaf total-routes {
type uint32;
description
"Total number of routes in the RIB.";
}
leaf total-active-routes {
type uint32;
description
"Total number of active routes in the RIB. An active
route is the route that is preferred over other routes
to the same destination prefix.";
}
leaf total-route-memory {
type uint64;
units "bytes";
description
"Total memory for all routes in the RIB.";
}
list protocol-statistics {
description
"RIB statistics for routing protocols installing
routes in the RIB.";
leaf protocol {
type identityref {
base rt:routing-protocol;
}
description
"Routing protocol installing routes in the RIB.";
}
leaf routes {
type uint32;
description
"Total number of routes in the RIB for the routing
protocol identified by the 'protocol' entry.";
}
leaf active-routes {
type uint32;
description
"Total number of active routes in the RIB for the
routing protocol identified by the 'protocol' entry.
An active route is preferred over other routes to the
same destination prefix.";
}
leaf route-memory {
type uint64;
units "bytes";
description
"Total memory for all routes in the RIB for the
routing protocol identified by the 'protocol'
entry.";
}
}
}
}
grouping repair-path {
description
"Grouping for the IP Fast Reroute (IPFRR) repair path.";
container repair-path {
description
"IPFRR next-hop repair path.";
leaf outgoing-interface {
type if:interface-state-ref;
description
"Name of the outgoing interface.";
}
leaf next-hop-address {
type inet:ip-address-no-zone;
description
"IP address of the next hop.";
}
leaf metric {
type uint32;
description
"The metric for the repair path. While the reroute
repair is local and the metric is not advertised
externally, the metric for the repair path is useful
for troubleshooting purposes.";
}
reference
"RFC 5714: IP Fast Reroute Framework";
}
}
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
"The preference is used to select among multiple static
routes. Routes with a lower next-hop preference value
are preferred, and equal-preference routes result in
Equal-Cost Multipath (ECMP) static routes.";
}
leaf tag {
type uint32;
default "0";
description
"The tag is a 32-bit opaque value associated with the
route that can be used for policy decisions such as
advertisement and filtering of the route.";
}
}
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
"The preference is used to select among multiple static
routes. Routes with a lower next-hop preference value
are preferred, and equal-preference routes result in
ECMP static routes.";
}
leaf tag {
type uint32;
default "0";
description
"The tag is a 32-bit opaque value associated with the
route that can be used for policy decisions such as
advertisement and filtering of the route.";
}
}
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
"The preference is used to select among multiple static
routes. Routes with a lower next-hop preference value
are preferred, and equal-preference routes result in
ECMP static routes.";
}
leaf tag {
type uint32;
default "0";
description
"The tag is a 32-bit opaque value associated with the
route that can be used for policy decisions such as
advertisement and filtering of the route.";
}
}
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
"The preference is used to select among multiple static
routes. Routes with a lower next-hop preference value
are preferred, and equal-preference routes result in
ECMP static routes.";
}
leaf tag {
type uint32;
default "0";
description
"The tag is a 32-bit opaque value associated with the
route that can be used for policy decisions such as
advertisement and filtering of the route.";
}
}
augment "/rt:routing/rt:ribs/rt:rib" {
description
"Augment a RIB with statistics.";
uses rib-statistics;
}
augment "/rt:routing/rt:ribs/rt:rib/"
+ "rt:routes/rt:route" {
description
"Augment a route in the RIB with common attributes.";
leaf metric {
when "not(derived-from("
+ "../rt:source-protocol, 'ospf:ospf')) "
+ "and not(derived-from( "
+ "../rt:source-protocol, 'isis:isis'))" {
description
"This augmentation is only valid for routes that don't
have OSPF or IS-IS as the source protocol. The YANG
data models for OSPF and IS-IS already include a
'metric' augmentation for routes.";
}
type uint32;
description
"The metric is a numeric value indicating the cost
of the route from the perspective of the routing
protocol installing the route. In general, routes with
a lower metric installed by the same routing protocol
are lower cost to reach and are preferable to routes
with a higher metric. However, metrics from different
routing protocols are not comparable.";
}
leaf-list tag {
when "not(derived-from("
+ "../rt:source-protocol, 'ospf:ospf')) "
+ "and not(derived-from( "
+ "../rt:source-protocol, 'isis:isis'))" {
description
"This augmentation is only valid for routes that don't
have OSPF or IS-IS as the source protocol. The YANG
data models for OSPF and IS-IS already include a 'tag'
augmentation for routes.";
}
type uint32;
description
"A tag is a 32-bit opaque value associated with the
route that can be used for policy decisions such as
advertisement and filtering of the route.";
}
leaf application-tag {
type uint32;
description
"The application-specific tag is an additional tag that
can be used by applications that require semantics and/or
policy different from that of the tag. For example,
the tag is usually automatically advertised in OSPF
AS-External Link State Advertisements (LSAs) while this
application-specific tag is not advertised implicitly.";
}
}
augment "/rt:routing/rt:ribs/rt:rib/"
+ "rt:routes/rt:route/rt:next-hop/rt:next-hop-options/"
+ "rt:simple-next-hop" {
description
"Augment 'simple-next-hop' with 'repair-path'.";
uses repair-path;
}
augment "/rt:routing/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
"Augment the next hop with a repair path.";
uses repair-path;
}
}
<CODE ENDS>
6. Security Considerations
The YANG module specified in this document defines a schema for data
that is designed to be accessed via network management protocols such
as NETCONF [RFC6241] or RESTCONF [RFC8040]. The lowest NETCONF layer
is the secure transport layer, and the mandatory-to-implement secure
transport is Secure Shell (SSH) [RFC6242]. The lowest RESTCONF layer
is HTTPS, and the mandatory-to-implement secure transport is TLS
[RFC8446].
The Network Configuration Access Control Model (NACM) [RFC8341]
provides the means to restrict access for particular NETCONF or
RESTCONF users to a preconfigured subset of all available NETCONF or
RESTCONF protocol operations and content.
There are a number of data nodes defined in the ietf-rib-
extension.yang module that are writable/creatable/deletable (i.e.,
config true, which is the default). These data nodes may be
considered sensitive or vulnerable in some network environments.
Write operations (e.g., edit-config) to these data nodes without
proper protection can have a negative effect on network operations.
These are the subtrees and data nodes and their sensitivity/
vulnerability:
* /v4ur:next-hop-options/v4ur:simple-next-hop/rib-ext:preference
* /v4ur:next-hop-options/v4ur:simple-next-hop/rib-ext:tag
* /v4ur:next-hop-options/v4ur:next-hop-list/v4ur:next-hop-list
/v4ur:next-hop/rib-ext:preference
* /v4ur:next-hop-options/v4ur:next-hop-list/v4ur:next-hop-list
/v4ur:next-hop/rib-ext:tag
* /v6ur:next-hop-options/v6ur:simple-next-hop/rib-ext:preference
* /v6ur:next-hop-options/v6ur:simple-next-hop/rib-ext:tag
* /v6ur:next-hop-options/v6ur:next-hop-list/v6ur:next-hop-list
/v6ur:next-hop/rib-ext:preference
* /v6ur:next-hop-options/v6ur:next-hop-list/v6ur:next-hop-list
/v6ur:next-hop/rib-ext:tag
For these augmentations to ietf-routing.yang, the ability to
delete, add, and modify IPv4 and IPv6 static route preferences and
tags would allow traffic to be misrouted.
Some of the readable data nodes in the ietf-rib-extension.yang module
may be considered sensitive or vulnerable in some network
environments. It is thus important to control read access (e.g., via
get, get-config, or notification) to these data nodes. These are the
subtrees and data nodes and their sensitivity/vulnerability:
* /rt:routing/rt:ribs/rt:rib/rib-ext:statistics
* /rt:routing/rt:ribs/rt:rib/rt:routes/rt:route/rib-ext:metric
* /rt:routing/rt:ribs/rt:rib/rt:routes/rt:route/rib-ext:tag
* /rt:routing/rt:ribs/rt:rib/rt:routes/rt:route/rib-ext:application-
tag
* /rt:route/rt:next-hop/rt:next-hop-options/rt:simple-next-hop/rib-
ext:repair-path
* /rt:routes/rt:route/rt:next-hop/rt:next-hop-options/rt:next-hop-
list/rt:next-hop-list/rt:next-hop/rib-ext:repair-path
Exposing the RIB will expose the routing topology of the network.
This may be undesirable due to the fact that such exposure may
facilitate other attacks. Additionally, network operators may
consider their topologies to be sensitive confidential data.
All the security considerations for writable and readable data nodes
defined in [RFC8349] apply to the augmentations described herein.
7. IANA Considerations
This document registers the following URI in the "IETF XML Registry"
[RFC3688].
URI: urn:ietf:params:xml:ns:yang:ietf-rib-extension
Registrant Contact: The IESG.
XML: N/A; the requested URI is an XML namespace.
IANA has registered the following YANG module in the "YANG Module
Names" registry [RFC6020].
Name: ietf-rib-extension
Namespace: urn:ietf:params:xml:ns:yang:ietf-rib-extension
Prefix: rib-ext
Reference: RFC 9403
8. References
8.1. Normative References
[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
DOI 10.17487/RFC3688, January 2004,
<https://www.rfc-editor.org/info/rfc3688>.
[RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for
the Network Configuration Protocol (NETCONF)", RFC 6020,
DOI 10.17487/RFC6020, October 2010,
<https://www.rfc-editor.org/info/rfc6020>.
[RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,
and A. Bierman, Ed., "Network Configuration Protocol
(NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011,
<https://www.rfc-editor.org/info/rfc6241>.
[RFC6242] Wasserman, M., "Using the NETCONF Protocol over Secure
Shell (SSH)", RFC 6242, DOI 10.17487/RFC6242, June 2011,
<https://www.rfc-editor.org/info/rfc6242>.
[RFC6991] Schoenwaelder, J., Ed., "Common YANG Data Types",
RFC 6991, DOI 10.17487/RFC6991, July 2013,
<https://www.rfc-editor.org/info/rfc6991>.
[RFC7950] Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
RFC 7950, DOI 10.17487/RFC7950, August 2016,
<https://www.rfc-editor.org/info/rfc7950>.
[RFC8040] Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017,
<https://www.rfc-editor.org/info/rfc8040>.
[RFC8341] Bierman, A. and M. Bjorklund, "Network Configuration
Access Control Model", STD 91, RFC 8341,
DOI 10.17487/RFC8341, March 2018,
<https://www.rfc-editor.org/info/rfc8341>.
[RFC8342] Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K.,
and R. Wilton, "Network Management Datastore Architecture
(NMDA)", RFC 8342, DOI 10.17487/RFC8342, March 2018,
<https://www.rfc-editor.org/info/rfc8342>.
[RFC8343] Bjorklund, M., "A YANG Data Model for Interface
Management", RFC 8343, DOI 10.17487/RFC8343, March 2018,
<https://www.rfc-editor.org/info/rfc8343>.
[RFC8349] Lhotka, L., Lindem, A., and Y. Qu, "A YANG Data Model for
Routing Management (NMDA Version)", RFC 8349,
DOI 10.17487/RFC8349, March 2018,
<https://www.rfc-editor.org/info/rfc8349>.
[RFC8446] Rescorla, E., "The Transport Layer Security (TLS) Protocol
Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018,
<https://www.rfc-editor.org/info/rfc8446>.
[RFC9129] Yeung, D., Qu, Y., Zhang, Z., Chen, I., and A. Lindem,
"YANG Data Model for the OSPF Protocol", RFC 9129,
DOI 10.17487/RFC9129, October 2022,
<https://www.rfc-editor.org/info/rfc9129>.
[RFC9130] Litkowski, S., Ed., Yeung, D., Lindem, A., Zhang, J., and
L. Lhotka, "YANG Data Model for the IS-IS Protocol",
RFC 9130, DOI 10.17487/RFC9130, October 2022,
<https://www.rfc-editor.org/info/rfc9130>.
[W3C.REC-xml-20081126]
Bray, T., Paoli, J., Sperberg-McQueen, M., Maler, E., and
F. Yergeau, "Extensible Markup Language (XML) 1.0 (Fifth
Edition)", World Wide Web Consortium Recommendation REC-
xml-20081126, November 2008,
<https://www.w3.org/TR/2008/REC-xml-20081126>.
8.2. Informative References
[RFC5714] Shand, M. and S. Bryant, "IP Fast Reroute Framework",
RFC 5714, DOI 10.17487/RFC5714, January 2010,
<https://www.rfc-editor.org/info/rfc5714>.
[RFC7951] Lhotka, L., "JSON Encoding of Data Modeled with YANG",
RFC 7951, DOI 10.17487/RFC7951, August 2016,
<https://www.rfc-editor.org/info/rfc7951>.
[RFC8340] Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams",
BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018,
<https://www.rfc-editor.org/info/rfc8340>.
[RFC8792] Watsen, K., Auerswald, E., Farrel, A., and Q. Wu,
"Handling Long Lines in Content of Internet-Drafts and
RFCs", RFC 8792, DOI 10.17487/RFC8792, June 2020,
<https://www.rfc-editor.org/info/rfc8792>.
Appendix A. Combined Tree Diagram
This appendix provides the combined ietf-routing.yang, ietf-ipv4-
unicast-routing.yang, ietf-ipv6-unicast-routing.yang, and ietf-rib-
extension.yang tree diagram.
module: ietf-routing
+--rw routing
+--rw router-id? yang:dotted-quad {router-id}?
+--ro interfaces
| +--ro interface* if:interface-ref
+--rw control-plane-protocols
| +--rw control-plane-protocol* [type name]
| +--rw type identityref
| +--rw name string
| +--rw description? string
| +--rw static-routes
| +--rw v4ur:ipv4
| | +--rw v4ur:route* [destination-prefix]
| | +--rw v4ur:destination-prefix inet:ipv4-prefix
| | +--rw v4ur:description? string
| | +--rw v4ur:next-hop
| | +--rw (v4ur:next-hop-options)
| | +--:(v4ur:simple-next-hop)
| | | +--rw v4ur:outgoing-interface?
| | | | if:interface-ref
| | | +--rw v4ur:next-hop-address?
| | | | inet:ipv4-address
| | | +--rw rib-ext:preference? uint32
| | | +--rw rib-ext:tag? uint32
| | +--:(v4ur:special-next-hop)
| | | +--rw v4ur:special-next-hop? enumeration
| | +--:(v4ur:next-hop-list)
| | +--rw v4ur:next-hop-list
| | +--rw v4ur:next-hop* [index]
| | +--rw v4ur:index string
| | +--rw v4ur:outgoing-interface?
| | | if:interface-ref
| | +--rw v4ur:next-hop-address?
| | | inet:ipv4-address
| | +--rw rib-ext:preference? uint32
| | +--rw rib-ext:tag? uint32
| +--rw v6ur:ipv6
| +--rw v6ur:route* [destination-prefix]
| +--rw v6ur:destination-prefix inet:ipv6-prefix
| +--rw v6ur:description? string
| +--rw v6ur:next-hop
| +--rw (v6ur:next-hop-options)
| +--:(v6ur:simple-next-hop)
| | +--rw v6ur:outgoing-interface?
| | | if:interface-ref
| | +--rw v6ur:next-hop-address?
| | | inet:ipv6-address
| | +--rw rib-ext:preference? uint32
| | +--rw rib-ext:tag? uint32
| +--:(v6ur:special-next-hop)
| | +--rw v6ur:special-next-hop? enumeration
| +--:(v6ur:next-hop-list)
| +--rw v6ur:next-hop-list
| +--rw v6ur:next-hop* [index]
| +--rw v6ur:index string
| +--rw v6ur:outgoing-interface?
| | if:interface-ref
| +--rw v6ur:next-hop-address?
| | inet:ipv6-address
| +--rw rib-ext:preference? uint32
| +--rw rib-ext:tag? uint32
+--rw ribs
+--rw rib* [name]
+--rw name string
+--rw address-family identityref
+--ro default-rib? boolean {multiple-ribs}?
+--ro routes
| +--ro route* []
| +--ro route-preference? route-preference
| +--ro next-hop
| | +--ro (next-hop-options)
| | +--:(simple-next-hop)
| | | +--ro outgoing-interface?
| | | | if:interface-ref
| | | +--ro v4ur:next-hop-address?
| | | | inet:ipv4-address
| | | +--ro v6ur:next-hop-address?
| | | | inet:ipv6-address
| | | +--ro rib-ext:repair-path
| | | +--ro rib-ext:outgoing-interface?
| | | | if:interface-state-ref
| | | +--ro rib-ext:next-hop-address?
| | | | inet:ip-address-no-zone
| | | +--ro rib-ext:metric? uint32
| | +--:(special-next-hop)
| | | +--ro special-next-hop? enumeration
| | +--:(next-hop-list)
| | +--ro next-hop-list
| | +--ro next-hop* []
| | +--ro outgoing-interface?
| | | if:interface-ref
| | +--ro v4ur:address?
| | | inet:ipv4-address
| | +--ro v6ur:address?
| | | inet:ipv6-address
| | +--ro rib-ext:repair-path
| | +--ro rib-ext:outgoing-interface?
| | | if:interface-state-ref
| | +--ro rib-ext:next-hop-address?
| | | inet:ip-address-no-zone
| | +--ro rib-ext:metric? uint32
| +--ro source-protocol identityref
| +--ro active? empty
| +--ro last-updated? yang:date-and-time
| +--ro v4ur:destination-prefix? inet:ipv4-prefix
| +--ro v6ur:destination-prefix? inet:ipv6-prefix
| +--ro rib-ext:metric? uint32
| +--ro rib-ext:tag* uint32
| +--ro rib-ext:application-tag? uint32
+---x active-route
| +---w input
| | +---w v4ur:destination-address? inet:ipv4-address
| | +---w v6ur:destination-address? inet:ipv6-address
| +--ro output
| +--ro route
| +--ro next-hop
| | +--ro (next-hop-options)
| | +--:(simple-next-hop)
| | | +--ro outgoing-interface?
| | | | if:interface-ref
| | | +--ro v4ur:next-hop-address?
| | | | inet:ipv4-address
| | | +--ro v6ur:next-hop-address?
| | | | inet:ipv6-address
| | +--:(special-next-hop)
| | | +--ro special-next-hop? enumeration
| | +--:(next-hop-list)
| | +--ro next-hop-list
| | +--ro next-hop* []
| | +--ro outgoing-interface?
| | | if:interface-ref
| | +--ro v4ur:next-hop-address?
| | | inet:ipv4-address
| | +--ro v6ur:next-hop-address?
| | | inet:ipv6-address
| +--ro source-protocol identityref
| +--ro active? empty
| +--ro last-updated? yang:date-and-time
| +--ro v4ur:destination-prefix? inet:ipv4-prefix
| +--ro v6ur:destination-prefix? inet:ipv6-prefix
+--rw description? string
+--ro rib-ext:statistics
+--ro rib-ext:total-routes? uint32
+--ro rib-ext:total-active-routes? uint32
+--ro rib-ext:total-route-memory? uint64
+--ro rib-ext:protocol-statistics* []
+--ro rib-ext:protocol? identityref
+--ro rib-ext:routes? uint32
+--ro rib-ext:active-routes? uint32
+--ro rib-ext:route-memory? uint64
Appendix B. ietf-rib-extension.yang example
The following is an XML example [W3C.REC-xml-20081126] using the RIB
extension module and RFC 8349.
| Note: '\' line wrapping per [RFC8792].
<routing xmlns="urn:ietf:params:xml:ns:yang:ietf-routing">
<control-plane-protocols>
<control-plane-protocol>
<type>static</type>
<name>static-routing-protocol</name>
<static-routes>
<ipv4 xmlns="urn:ietf:params:xml:ns:yang:\
ietf-ipv4-unicast-routing">
<route>
<destination-prefix>0.0.0.0/0</destination-prefix>
<next-hop>
<next-hop-address>192.0.2.2</next-hop-address>
<preference xmlns="urn:ietf:params:xml:ns:yang:\
ietf-rib-extension">30</preference>
<tag xmlns="urn:ietf:params:xml:ns:yang:\
ietf-rib-extension">99</tag>
</next-hop>
</route>
</ipv4>
<ipv6 xmlns="urn:ietf:params:xml:ns:yang:\
ietf-ipv6-unicast-routing">
<route>
<destination-prefix>::/0</destination-prefix>
<next-hop>
<next-hop-address>2001:db8:aaaa::1111</next-hop-address>
<preference xmlns="urn:ietf:params:xml:ns:yang:\
ietf-rib-extension">30</preference>
<tag xmlns="urn:ietf:params:xml:ns:yang:\
ietf-rib-extension">66</tag>
</next-hop>
</route>
</ipv6>
</static-routes>
</control-plane-protocol>
</control-plane-protocols>
<ribs>
<rib>
<name>ipv4-primary</name>
<address-family xmlns:v4ur="urn:ietf:params:xml:ns:yang:\
ietf-ipv4-unicast-routing">v4ur:ipv4-unicast</address-family>
<default-rib>true</default-rib>
<routes>
<route>
<destination-prefix xmlns="urn:ietf:params:xml:ns:yang:\
ietf-ipv4-unicast-routing">0.0.0.0/0</destination-prefix>
<next-hop>
<next-hop-address xmlns="urn:ietf:params:xml:ns:yang:\
ietf-ipv4-unicast-routing">192.0.2.2</next-hop-address>
</next-hop>
<route-preference>5</route-preference>
<source-protocol>static</source-protocol>
<last-updated>2015-10-24T18:02:45+02:00</last-updated>
</route>
<route>
<destination-prefix xmlns="urn:ietf:params:xml:ns:yang:\
ietf-ipv4-unicast-routing">198.51.100.0/24\
</destination-prefix>
<next-hop>
<next-hop-address xmlns="urn:ietf:params:xml:ns:yang:\
ietf-ipv4-unicast-routing">192.0.2.2</next-hop-address>
<repair-path xmlns="urn:ietf:params:xml:ns:yang:\
ietf-rib-extension">
<next-hop-address>203.0.113.1</next-hop-address>
<metric>200</metric>
</repair-path>
</next-hop>
<route-preference>120</route-preference>
<source-protocol xmlns:rip="urn:ietf:params:xml:ns:yang:\
ietf-rip">rip:rip</source-protocol>
<last-updated>2015-10-24T18:02:45+02:00</last-updated>
</route>
</routes>
</rib>
<rib>
<name>ipv6-primary</name>
<address-family xmlns:v6ur="urn:ietf:params:xml:ns:yang:\
ietf-ipv6-unicast-routing">v6ur:ipv6-unicast</address-family>
<default-rib>true</default-rib>
<routes>
<route>
<destination-prefix xmlns="urn:ietf:params:xml:ns:yang:\
ietf-ipv6-unicast-routing">0::/0</destination-prefix>
<next-hop>
<next-hop-address xmlns="urn:ietf:params:xml:ns:yang:\
ietf-ipv6-unicast-routing">2001:db8:aaaa::1111\
</next-hop-address>
</next-hop>
<route-preference>5</route-preference>
<source-protocol>static</source-protocol>
<last-updated>2015-10-24T18:02:45+02:00</last-updated>
</route>
<route>
<destination-prefix xmlns="urn:ietf:params:xml:ns:yang:\
ietf-ipv6-unicast-routing">2001:db8:bbbb::/64\
</destination-prefix>
<next-hop>
<next-hop-address xmlns="urn:ietf:params:xml:ns:yang:\
ietf-ipv6-unicast-routing">2001:db8:aaaa::1111\
</next-hop-address>
<repair-path xmlns="urn:ietf:params:xml:ns:yang:\
ietf-rib-extension">
<next-hop-address>2001:db8:cccc::2222</next-hop-address>
<metric>200</metric>
</repair-path>
</next-hop>
<route-preference>120</route-preference>
<source-protocol xmlns:rip="urn:ietf:params:xml:ns:yang:\
ietf-rip">rip:rip</source-protocol>
<last-updated>2015-10-24T18:02:45+02:00</last-updated>
</route>
</routes>
</rib>
</ribs>
</routing>
The following is the same example using JSON format [RFC7951].
{
"ietf-routing:routing": {
"control-plane-protocols": {
"control-plane-protocol": [
{
"type": "static",
"name": "static-routing-protocol",
"static-routes": {
"ietf-ipv4-unicast-routing:ipv4": {
"route": [
{
"destination-prefix": "0.0.0.0/0",
"next-hop": {
"next-hop-address": "192.0.2.2",
"ietf-rib-extension:preference": 30,
"ietf-rib-extension:tag": 99
}
}
]
},
"ietf-ipv6-unicast-routing:ipv6": {
"route": [
{
"destination-prefix": "::/0",
"next-hop": {
"next-hop-address": "2001:db8:aaaa::1111",
"ietf-rib-extension:preference": 30,
"ietf-rib-extension:tag": 66
}
}
]
}
}
}
]
},
"ribs": {
"rib": [
{
"name": "ipv4-primary",
"address-family": "ietf-ipv4-unicast-routing:ipv4-unicast",
"default-rib": true,
"routes": {
"route": [
{
"next-hop": {
"ietf-ipv4-unicast-routing:next-hop-address": \
"192.0.2.2"
},
"route-preference": 5,
"source-protocol": "static",
"last-updated": "2015-10-24T18:02:45+02:00",
"ietf-ipv4-unicast-routing:destination-prefix": \
"0.0.0.0/0"
},
{
"next-hop": {
"ietf-rib-extension:repair-path": {
"next-hop-address": "203.0.113.1",
"metric": 200
},
"ietf-ipv4-unicast-routing:next-hop-address": \
"192.0.2.2"
},
"route-preference": 120,
"source-protocol": "ietf-rip:rip",
"last-updated": "2015-10-24T18:02:45+02:00",
"ietf-ipv4-unicast-routing:destination-prefix": \
"198.51.100.0/24"
}
]
}
},
{
"name": "ipv6-primary",
"address-family": "ietf-ipv6-unicast-routing:ipv6-unicast",
"default-rib": true,
"routes": {
"route": [
{
"next-hop": {
"ietf-ipv6-unicast-routing:next-hop-address": \
"2001:db8:aaaa::1111"
},
"route-preference": 5,
"source-protocol": "static",
"last-updated": "2015-10-24T18:02:45+02:00",
"ietf-ipv6-unicast-routing:destination-prefix": "::/0"
},
{
"next-hop": {
"ietf-rib-extension:repair-path": {
"next-hop-address": "2001:db8:cccc::2222",
"metric": 200
},
"ietf-ipv6-unicast-routing:next-hop-address": \
"2001:db8:aaaa::1111"
},
"route-preference": 120,
"source-protocol": "ietf-rip:rip",
"last-updated": "2015-10-24T18:02:45+02:00",
"ietf-ipv6-unicast-routing:destination-prefix": \
"2001:db8:bbbb::/64"
}
]
}
}
]
}
}
}
Acknowledgments
The authors wish to thank Les Ginsberg, Krishna Deevi, and Suyoung
Yoon for their helpful comments and suggestions.
The authors wish to thank Tom Petch, Rob Wilton, Chris Hopps, Martin
Björklund, Jeffrey Zhang, Éric Vyncke, Lars Eggert, and Bo Wu for
their reviews and comments.
Authors' Addresses
Acee Lindem
LabN Consulting, L.L.C.
301 Midenhall Way
Cary, NC 27513
United States of America
Email: acee.ietf@gmail.com
Yingzhen Qu
Futurewei Technologies
2330 Central Expressway
Santa Clara, CA 95050
United States of America
Email: yingzhen.qu@futurewei.com