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
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provisions of BCP 78 and BCP 79.
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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
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include Simplified BSD License text as described in Section 4.e of
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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.
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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.
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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
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4. RIB YANG Model
<CODE BEGINS> 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.
";
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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";
}
}
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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;
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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
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"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;
}
}
<CODE ENDS>
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
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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.
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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
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