MPLS Working Group
Internet Engineering Task Force (IETF) T. Saad
Internet-Draft
Request for Comments: 8960 Juniper Networks
Intended status:
Category: Standards Track K. Raza
Expires: April 29, 2021
ISSN: 2070-1721 R. Gandhi
Cisco Systems Inc Systems, Inc.
X. Liu
Volta Networks
V. Beeram
Juniper Networks
October 26,
December 2020
A YANG Data Model for MPLS Base
draft-ietf-mpls-base-yang-17
Abstract
This document contains a specification of the MPLS base YANG data
model. The MPLS base YANG data model serves as a base framework for
configuring and managing an MPLS switching subsystem on an MPLS-
enabled router. It is expected that other MPLS YANG data models
(e.g.
(e.g., MPLS Label Switched Path (LSP) Static, LDP static, LDP, or RSVP-TE YANG
data models) will augment the MPLS base YANG data model.
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 an Internet Standards Track document.
This document is a product of the Internet Engineering Task Force
(IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list It represents the consensus of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid the IETF community. It has
received public review and has been approved for a maximum publication by the
Internet Engineering Steering Group (IESG). Further information on
Internet Standards is available in Section 2 of six months RFC 7841.
Information about the current status of this document, any errata,
and how to provide feedback on it may be updated, replaced, or obsoleted by other documents obtained 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 April 29, 2021.
https://www.rfc-editor.org/info/rfc8960.
Copyright Notice
Copyright (c) 2020 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
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described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3
1.2. Acronyms and Abbreviations . . . . . . . . . . . . . . . 3
2. MPLS Base Model . . . . . . . . . . . . . . . . . . . . . . . 4
2.1. Model Overview . . . . . . . . . . . . . . . . . . . . . 4
2.2. Model Organization . . . . . . . . . . . . . . . . . . . 4
2.3. Model Design . . . . . . . . . . . . . . . . . . . . . . 6
2.4. Model Tree Diagram . . . . . . . . . . . . . . . . . . . 8
2.5. Model YANG Module . . . . . . . . . . . . . . . . . . . . 9
3. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 19 Model Overview
2.2. Model Organization
2.3. Model Design
2.4. Model Tree Diagram
2.5. MPLS Base YANG Module
3. IANA Considerations
4. Security Considerations . . . . . . . . . . . . . . . . . . . 20
5. Acknowledgement . . . . . . . . . . . . . . . . . . . . . . . 21
6. References
5.1. Normative References
5.2. Informative References
Appendix A. Data Tree Instance Example . . . . . . . . . . . 21
7.
Acknowledgments
Contributors . . . . . . . . . . . . . . . . . . . . . . . . 27
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 27
8.1. Normative References . . . . . . . . . . . . . . . . . . 27
8.2. Informative References . . . . . . . . . . . . . . . . . 29
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 29
1. Introduction
A core routing YANG data model is defined in [RFC8349], and [RFC8349]; it provides a
basis for the development of routing data models for specific Address
Families (AFs). Specifically, [RFC8349] defines a model for a
generic Routing Information Base (RIB) that is Address-
Family (AF) AF agnostic.
[RFC8349] also defines two instances of RIBs based on the generic RIB
model for IPv4 and IPv6 AFs.
The MPLS base model that is defined in this document augments the generic RIB
model defined in [RFC8349] with additional data that enables MPLS
forwarding for the one or more specific destination prefix(es) prefixes present in the
one or more AF RIB(s) RIBs, as described in the MPLS architecture document
[RFC3031].
The MPLS base model also defines a new instance of the generic RIB
YANG data model as defined in [RFC8349] to store native MPLS routes.
The native MPLS RIB instance stores route(s) one or more routes that are not
associated with other AF instance RIBs (such as IPv4, IPv4 or IPv6 instance RIB(s)),
RIBs) but are enabled for MPLS forwarding. Examples of such native
MPLS routes are routes programmed by RSVP on one or more transit MPLS router(s)
routers along the path of a Label Switched Path (LSP). Other example(s)
examples are MPLS routes that cross-connect to specific Layer-2 Layer 2
adjacencies, such as
Layer-2 Layer 2 Attachment Circuit(s) (ACs)), Circuits (ACs); or Layer-3 Layer 3
adjacencies, such as
Segment-Routing Segment Routing (SR) Adjacency Segments (Adj-SIDs) (Adj-
SIDs) as described in [RFC8402].
The MPLS base YANG data model serves as a basis for future
development of MPLS YANG data models covering more-sophisticated MPLS
feature(s) features and sub-system(s).
subsystems that are more sophisticated. The main purpose is to
provide essential building blocks for other YANG data models
involving different control-plane protocols, protocols and MPLS functions.
To this end, it is expected that the MPLS base data model will be
augmented by a number of other YANG modules developed at by the IETF (e.g.
(e.g., by the TEAS and MPLS working groups). Working Groups).
The YANG module defined in this document conforms to the Network
Management Datastore Architecture (NMDA) [RFC8342].
1.1. Terminology
The terminology for describing YANG data models is found in
[RFC7950].
1.2. Acronyms and Abbreviations
MPLS: Multiprotocol Label Switching
RIB: Routing Information Base
LSP: Label Switched Path
LSR: Label Switching Router
LER: Label Edge Router
FEC: Forwarding Equivalence Class
NHLFE: Next Hop Label Forwarding Entry
ILM: Incoming Label Map
2. MPLS Base Model
This document describes the 'ietf-mpls' "ietf-mpls" YANG module that module, which provides
base components of the MPLS data model. It is expected that other
MPLS YANG modules will augment 'ietf-mpls' the "ietf-mpls" YANG module for other
MPLS
extension extensions to provision Label Switched Paths (LSPs) (e.g. LSPs (e.g., MPLS
Static, static, MPLS LDP LDP, or
MPLS RSVP-TE LSP(s)). LSPs).
2.1. Model Overview
This document models MPLS labeled MPLS-labeled routes as an augmentation of the
generic routing RIB data model as defined in [RFC8349]. For example,
IP prefix routes (e.g. (e.g., routes stored in IPv4 or IPv6 RIBs) are
augmented to carry additional data to enable it them for MPLS
forwarding.
This document also defines a new instance of the generic RIB model
defined in [RFC8349] to store one or more native MPLS route(s) routes
(described further in Section 2.3) by extending the identity 'address-family'
"address-family" defined in [RFC8349] with a new "mpls" identity as suggested in identity; see
Section 3 of [RFC8349].
2.2. Model Organization
Routing +---------------+ v: import
YANG module | ietf-routing | o: augment
+---------------+
o
|
v
MPLS base +-----------+ v: import
YANG module | ietf-mpls | o: augment
+-----------+
o o------+
| \
v v
+-------------------+ +---------------------+
MPLS Static static | ietf-mpls-static@ | | ietf-mpls-ldp.yang@ | . .
LSP YANG +-------------------+ +---------------------+
module
@: not in this document, document; shown for illustration only
Figure 1: Relationship between MPLS modules Modules
The 'ietf-mpls' "ietf-mpls" YANG module defines the following identities:
mpls:
This identity
Identity that extends the 'address-family' "address-family" identity for of RIB
instance(s) identity
instances, as defined in [RFC8349] [RFC8349], to represent the native MPLS
RIB instance.
label-block-alloc-mode:
A base YANG identity for one or more supported label block label-block
allocation mode(s). modes.
The 'ietf-mpls' "ietf-mpls" YANG module contains the following high-level types
and groupings:
mpls-operations-type:
An enumeration type that represents support for possible MPLS
operation types (impose-and-forward, pop-and-forward, pop-impose-
and-forward, and pop-and-lookup) pop-and-lookup).
nhlfe-role:
An enumeration type that represents the role of the NHLFE entry. Next Hop Label
Forwarding Entry (NHLFE).
nhlfe-single-contents:
A YANG grouping that describes a single Next Hop Label Forwarding
Entry (NHLFE) NHLFE and its associated
parameters as described in the MPLS architecture document
[RFC3031]. This grouping is specific to the case when a single next-hop
next hop is associated with the route.
The NHLFE is used when forwarding a labeled packet. It contains the
following information:
1. the The packet's next hop. For 'nhlfe-single-contents' "nhlfe-single-contents", only a
single next hop is expected, while for 'nhlfe-multiple-contents' "nhlfe-multiple-contents",
multiple next hops are possible.
2. the The operation to perform on the packet's label stack; this stack. This can
be one of the following operations: a) replace
a. Replace the label at the top of the label stack with one or
more specified new label b) pop labels.
b. Pop the label stack c) replace stack.
c. Replace the label at the top of the label stack with a
specified new label, and then push one or more specified new
labels onto the label stack. d) push
d. Push one or more
label(s) on labels onto an unlabeled packet
It packet.
The NHLFE may also contain:
d) the data link
1. The data-link encapsulation to use when transmitting the packet
e) the packet.
2. The way to encode the label stack when transmitting the packet
f) any packet.
3. Any other information needed in order to properly dispose of the
packet.
nhlfe-multiple-contents:
A YANG grouping that describes a set of NHLFE(s) NHLFEs and their
associated parameters as described in the MPLS architecture
document [RFC3031]. This grouping is used when multiple next-hops next hops
are associated with the route.
interfaces-mpls:
A YANG grouping that describes the list of MPLS enabled MPLS-enabled interfaces
on a device.
label-blocks:
A YANG grouping that describes the list of assigned MPLS label
blocks and their properties.
rib-mpls-properties:
A YANG grouping for the augmentation of the generic RIB with MPLS
label forwarding data as defined in [RFC3031].
rib-active-route-mpls-input:
A YANG grouping for the augmentation to the 'active-route' "active-route" RPC
that is specific to the MPLS RIB instance.
2.3. Model Design
The MPLS routing model is based on the core routing data model
defined in [RFC8349]. Figure 2 shows the extensions introduced by
the MPLS base model on defined RIB(s). RIBs.
+-----------------+
| MPLS base model |
+-----------------+
____/ | |_____ |________
/ | \ \
/ | \ \
o o o +
+---------+ +---------+ +--------+ +-----------+
| RIB(v4) | | RIB(v6) | | RIB(x) | | RIB(mpls) |
+---------+ +---------+ +--------+ +-----------+
+: created by the MPLS base model
o: augmented by the MPLS base model
Figure 2: Relationship between MPLS model Model and RIB instances Instances
As shown in Figure 2, the MPLS base YANG data model augments defined
instance(s)
instances of AF RIB(s) RIBs with additional data that enables MPLS
forwarding for destination prefix(es) store prefixes stored in such RIB(s). RIBs. For
example, an IPv4 prefix stored in RIB(v4) is augmented to carry a an
MPLS local label and per next-hop one or more per-next-hop remote label(s) labels to enable
MPLS forwarding for such a prefix.
The MPLS base model also creates a separate instance of the generic
RIB model defined in [RFC8349] to store one or more MPLS native route(s)
routes that are enabled for MPLS forwarding, forwarding but are not stored in one
or more other AF RIB(s). RIBs.
Some examples of such native MPLS routes are:
o routes
* Routes programmed by RSVP on Label Switched Router(s) Switching Routers (LSRs) along
the path of a Label Switched Path (LSP),
o routes an LSP,
* Routes that cross-connect an MPLS local label to a Layer-2, Layer 2 or
Layer-3 VRF,
o routes
Layer 3 Virtual Routing and Forwarding (VRF) entity,
* Routes that cross-connect an MPLS local label to a specific
Layer-2 Layer
2 adjacency or interface, such as Layer-2 Layer 2 Attachment
Circuit(s) Circuits
(ACs), or
o routes
* Routes that cross-connect an MPLS local label to a Layer-3 Layer 3
adjacency or interface - interface, such as MPLS Segment-Routing Segment Routing (SR)
Adjacency Segments (Adj-SIDs), (Adj-SIDs) or SR MPLS Binding SIDs, etc. SIDs as defined
in [RFC8402].
2.4. Model Tree Diagram
The MPLS base tree diagram that diagram, which follows the notation defined in
[RFC8340]
[RFC8340], is shown in Figure 3.
module: ietf-mpls
augment /rt:routing:
+--rw mpls
+--rw ttl-propagate? boolean
+--rw mpls-label-blocks
| +--rw mpls-label-block* [index]
| +--rw index string
| +--rw start-label? rt-types:mpls-label
| +--rw end-label? rt-types:mpls-label
| +--rw block-allocation-mode? identityref
| +--ro inuse-labels-count? yang:gauge32
+--rw interfaces
+--rw interface* [name]
+--rw name if:interface-ref
+--rw mpls-enabled? boolean
+--rw maximum-labeled-packet? uint32
augment /rt:routing/rt:ribs/rt:rib/rt:routes/rt:route:
+--ro mpls-enabled? boolean
+--ro mpls-local-label? rt-types:mpls-label
+--ro destination-prefix? -> ../mpls-local-label
+--ro route-context? string
augment /rt:routing/rt:ribs/rt:rib/rt:routes/rt:route/rt:next-hop
/rt:next-hop-options/rt:simple-next-hop:
+--ro mpls-label-stack
+--ro entry* [id]
+--ro id uint8
+--ro label? rt-types:mpls-label
+--ro ttl? uint8
+--ro traffic-class? uint8
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 index? string
+--ro backup-index? string
+--ro loadshare? uint16
+--ro role? nhlfe-role
+--ro mpls-label-stack
+--ro entry* [id]
+--ro id uint8
+--ro label? rt-types:mpls-label
+--ro ttl? uint8
+--ro traffic-class? uint8
augment /rt:routing/rt:ribs/rt:rib/rt:active-route/rt:input:
+---w destination-address? -> ../mpls-local-label
+---w mpls-local-label? rt-types:mpls-label
augment /rt:routing/rt:ribs/rt:rib/rt:active-route/rt:output
/rt:route/rt:next-hop/rt:next-hop-options
/rt:simple-next-hop:
+-- mpls-label-stack
+-- entry* [id]
+-- id uint8
+-- label? rt-types:mpls-label
+-- ttl? uint8
+-- traffic-class? uint8
augment /rt:routing/rt:ribs/rt:rib/rt:active-route/rt:output
/rt:route/rt:next-hop/rt:next-hop-options
/rt:next-hop-list/rt:next-hop-list/rt:next-hop:
+-- index? string
+-- backup-index? string
+-- loadshare? uint16
+-- role? nhlfe-role
+-- mpls-label-stack
+-- entry* [id]
+-- id uint8
+-- label? rt-types:mpls-label
+-- ttl? uint8
+-- traffic-class? uint8
Figure 3: MPLS Base tree diagram Tree Diagram
2.5. Model MPLS Base YANG Module
This section describes the 'ietf-mpls' "ietf-mpls" YANG module that module, which provides
base components of the MPLS data model. Other YANG module(s) modules may
import and augment the base MPLS base module to add feature specific feature-specific data.
The ietf-mpls "ietf-mpls" YANG module imports the following YANG modules:
o ietf-routing
* "ietf-routing" as defined in [RFC8349]
o ietf-routing-types
* "ietf-routing-types" as defined in [RFC8294]
o ietf-interfaces
* "ietf-yang-types" as defined in [RFC6991]
* "ietf-interfaces" as defined in [RFC8343]
This YANG module also references the following RFCs in defining the
types and
types, YANG grouping groupings, and other features of the YANG module: [RFC3032],
[RFC3031], [RFC3032], [RFC4090], [RFC5714], and [RFC7424].
<CODE BEGINS> file "ietf-mpls@2020-10-26.yang" "ietf-mpls@2020-11-19.yang"
module ietf-mpls {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-mpls";
/* Replace with IANA when assigned */
prefix mpls;
import ietf-routing {
prefix rt;
reference
"RFC8349:
"RFC 8349: A YANG Data Model for Routing Management"; Management
(NMDA Version)";
}
import ietf-routing-types {
prefix rt-types;
reference
"RFC8294:Common
"RFC 8294: Common YANG Data Types for the Routing Area";
}
import ietf-yang-types {
prefix yang;
reference
"RFC6991:
"RFC 6991: Common YANG Data Types";
}
import ietf-interfaces {
prefix if;
reference
"RFC8343:
"RFC 8343: A YANG Data Model for Interface Management";
}
organization
"IETF MPLS Working Group";
contact
"WG Web: <http://tools.ietf.org/wg/mpls/> <https://datatracker.ietf.org/wg/mpls/>
WG List: <mailto:mpls@ietf.org>
Editor: Tarek Saad
<mailto:tsaad@juniper.net>
Editor: Kamran Raza
<mailto:skraza@cisco.com>
Editor: Rakesh Gandhi
<mailto:rgandhi@cisco.com>
Editor: Xufeng Liu
<mailto: xufeng.liu.ietf@gmail.com>
<mailto:xufeng.liu.ietf@gmail.com>
Editor: Vishnu Pavan Beeram
<mailto:vbeeram@juniper.net>";
description
"This YANG module defines the essential components for the
management of the MPLS subsystem. The model fully conforms
to the Network Management Datastore Architecture (NMDA).
Copyright (c) 2018 2020 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
(https://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX; 8960; see the
RFC itself for full legal notices.";
// RFC Ed.: replace XXXX with actual RFC number and remove this
// note.
// RFC Ed.: update the date below with the date of RFC publication
// and remove this note.
revision 2020-10-26 2020-11-19 {
description
"Initial revision.";
reference
"RFC XXXX: 8960: A YANG Data Model for base MPLS"; MPLS Base";
}
/* Identities */
identity mpls {
base rt:address-family;
description
"This identity represents the MPLS address family.";
}
identity mpls-unicast {
base mpls:mpls;
description
"This identity represents the MPLS unicast address family.";
}
identity label-block-alloc-mode {
description
"Base identity for label-block allocation mode.";
}
identity label-block-alloc-mode-manager {
base label-block-alloc-mode;
description
"Label block
"Label-block allocation on the reserved block
is managed by the label manager.";
}
identity label-block-alloc-mode-application {
base label-block-alloc-mode;
description
"Label block
"Label-block allocation on the reserved block
is managed by the application.";
}
/**
* Typedefs
*/
typedef mpls-operations-type {
type enumeration {
enum impose-and-forward {
description
"Operation to impose one or more outgoing label(s) labels and
forward to
next-hop."; the next hop.";
}
enum pop-and-forward {
description
"Operation to pop the incoming label and forward to next-hop."; the
next hop.";
}
enum pop-impose-and-forward {
description
"Operation to pop the incoming label, impose one or more
outgoing label(s) labels, and forward to next-hop."; the next hop.";
}
enum swap-and-forward {
description
"Operation to swap the incoming label, label with the outgoing
label and forward to next-hop."; the next hop.";
}
enum pop-and-lookup {
description
"Operation to pop the incoming label and perform
a lookup.";
}
}
description
"MPLS operations types.";
"Types of MPLS operations.";
}
typedef nhlfe-role {
type enumeration {
enum primary {
description
"Next-hop
"The next hop acts as the primary for carrying traffic.";
}
enum backup {
description
"Next-hop
"The next hop acts as the backup.";
}
enum primary-and-backup {
description
"Next-hop
"The next hop simultaneously acts as both the primary and
the backup simultaneously for carry carrying traffic.";
}
}
description
"The next-hop role.";
"Role of the next hop.";
}
grouping nhlfe-single-contents {
description
"A grouping that describes a single Next Hop Label Forwarding
Entry (NHLFE) and its associated parameters as described in
the MPLS architecture. This grouping is specific to the case
when a single next-hop next hop is associated with the route.";
uses rt-types:mpls-label-stack;
}
grouping nhlfe-multiple-contents {
description
"A grouping that describes a set of NHLFE(s) NHLFEs and their
associated parameters as described in the MPLS
architecture. This grouping is used when multiple next-hops next hops
are associated with the route.";
leaf index {
type string;
description
"A user-specified identifier utilised utilized to uniquely
reference the next-hop entry in the next-hop list.
The value of this index has no semantic meaning
other than for referencing the entry.";
}
leaf backup-index {
type string;
description
"A user-specified identifier utilised utilized to uniquely
reference the backup next-hop entry in the NHLFE list.
The value of this index has no semantic meaning
other than for referencing the entry.";
reference
"RFC4090 and RFC5714";
"RFC 4090: Fast Reroute Extensions to RSVP-TE for LSP Tunnels
RFC 5714: IP Fast Reroute Framework";
}
leaf loadshare {
type uint16;
default "1";
description
"This value is used to compute a loadshare load share to perform un-equal
unequal load balancing when multiple outgoing next-hop(s) next hops are
specified. A share is computed as a ratio of this number to
the total under all next-hops(s)."; next hops.";
reference
"RFC7424, section 5.4,
RFC3031, section
"RFC 3031: Multiprotocol Label Switching Architecture,
Sections 3.11 and 3.12."; 3.12
RFC 7424: Mechanisms for Optimizing Link Aggregation Group
(LAG) and Equal-Cost Multipath (ECMP) Component Link
Utilization in Networks, Section 5.4";
}
leaf role {
type nhlfe-role;
description
"NHLFE role.";
"Role of the NHLFE.";
}
uses nhlfe-single-contents;
}
grouping interfaces-mpls {
description
"List of MPLS interfaces.";
container interfaces {
description
"List of MPLS enabled interaces."; MPLS-enabled interfaces.";
list interface {
key "name";
description
"MPLS enabled
"MPLS-enabled interface entry.";
leaf name {
type if:interface-ref;
description
"A reference to the name of a an interface in the system
that is to be enabled for MPLS.";
}
leaf mpls-enabled {
type boolean;
default "false";
description
"'true' if mpls MPLS encapsulation is enabled on the
interface.
'false' if mpls MPLS encapsulation is disabled on the
interface.";
}
leaf maximum-labeled-packet {
type uint32;
units "octets";
description
"Maximum labeled packet size.";
reference
"RFC3032, section 3.2.";
"RFC 3032: MPLS Label Stack Encoding, Section 3.2";
}
}
}
}
grouping globals {
description
"MPLS global configuration grouping.";
leaf ttl-propagate {
type boolean;
default "true";
description
"Propagate TTL between IP and MPLS.";
}
}
grouping label-blocks {
description
"Label-block allocation grouping.";
container mpls-label-blocks {
description
"Label-block allocation container.";
list mpls-label-block {
key "index";
description
"List of MPLS label-blocks."; label blocks.";
leaf index {
type string;
description
"A user-specified identifier utilised utilized to uniquely
reference an MPLS label block.";
}
leaf start-label {
type rt-types:mpls-label;
must '. <= ../end-label' {
error-message
"The start-label "'start-label' must be less than or equal "
+ "to end-label"; 'end-label'";
}
description
"Label-block start.";
}
leaf end-label {
type rt-types:mpls-label;
must '. >= ../start-label' {
error-message
"The end-label "'end-label' must be greater than or equal "
+ "to start-label"; "equal to 'start-label'";
}
description
"Label-block end.";
}
leaf block-allocation-mode {
type identityref {
base label-block-alloc-mode;
}
description
"Label-block allocation mode.";
}
leaf inuse-labels-count {
when "derived-from-or-self(../block-allocation-mode, "
+ "'mpls:label-block-alloc-mode-manager')";
type yang:gauge32;
config false;
description
"Label-block inuse
"Number of labels count."; in use in the label block.";
}
}
}
}
grouping rib-mpls-properties {
description
"A grouping of native MPLS RIB properties.";
leaf destination-prefix {
type leafref {
path "../mpls-local-label";
}
description
"MPLS destination prefix.";
}
leaf route-context {
type string;
description
"A context associated with the native MPLS route.";
}
}
grouping rib-active-route-mpls-input {
description
"A grouping applicable to native MPLS RIB 'active-route'
RPC input augmentation.";
leaf destination-address {
type leafref {
path "../mpls-local-label";
}
description
"MPLS native active route 'active-route' destination.";
}
leaf mpls-local-label {
type rt-types:mpls-label;
description
"MPLS local label.";
}
}
augment "/rt:routing" {
description
"MPLS augmentation.";
container mpls {
description
"MPLS container, container to be used as an augmentation target node
for the configuration of other MPLS sub-features config, e.g. sub-features, e.g.,
MPLS static LSP, Label Switched Paths (LSPs), MPLS LDP LSPs,
and Trafic Traffic Engineering MPLS LSP Tunnels, etc."; Tunnels.";
uses globals;
uses label-blocks;
uses interfaces-mpls;
}
}
/* Augmentation of MPLS routes augmentation */
augment "/rt:routing/rt:ribs/rt:rib/rt:routes/rt:route" {
description
"This augmentation is applicable to all MPLS routes.";
leaf mpls-enabled {
type boolean;
default "false";
description
"Indicates whether MPLS is enabled for this route.";
}
leaf mpls-local-label {
when "../mpls-enabled = 'true'";
type rt-types:mpls-label;
description
"MPLS local label associated with the route.";
}
uses rib-mpls-properties {
/* MPLS AF Address Family (AF) augmentation to the
native MPLS RIB */
when "derived-from-or-self(../../rt:address-family, "
+ "'mpls:mpls')" {
description
"This augment is valid only for routes of the native MPLS
RIB.";
}
}
}
/* MPLS simple-next-hop augmentation */
augment "/rt:routing/rt:ribs/rt:rib/rt:routes/rt:route/"
+ "rt:next-hop/rt:next-hop-options/rt:simple-next-hop" {
description
"Augment
"Augments the 'simple-next-hop' case in IP unicast routes.";
uses nhlfe-single-contents {
when "/rt:routing/rt:ribs/rt:rib/rt:routes/rt:route"
+ "/mpls:mpls-enabled = 'true'";
}
}
/* MPLS next-hop-list augmentation */
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
"This leaf augments the 'next-hop-list' case of IP unicast
routes.";
uses nhlfe-multiple-contents {
when "/rt:routing/rt:ribs/rt:rib/rt:routes/rt:route"
+ "/mpls:mpls-enabled = 'true'";
}
}
/* MPLS RPC input augmentation */
augment "/rt:routing/rt:ribs/rt:rib/rt:active-route/rt:input" {
description
"Input MPLS augmentation for the 'active-route' action
statement.";
uses rib-active-route-mpls-input {
/* MPLS AF augmentation to the native MPLS RIB */
when "derived-from-or-self(../rt:address-family, "
+ "'mpls:mpls')" {
description
"This augment is valid only for routes of the native MPLS
RIB.";
}
}
}
/* MPLS RPC output augmentation */
augment "/rt:routing/rt:ribs/rt:rib/rt:active-route/"
+ "rt:output/rt:route/"
+ "rt:next-hop/rt:next-hop-options/rt:simple-next-hop" {
description
"Output MPLS augmentation for the 'active-route' action
statement.";
uses nhlfe-single-contents;
}
augment "/rt:routing/rt:ribs/rt:rib/rt:active-route/"
+ "rt:output/rt:route/"
+ "rt:next-hop/rt:next-hop-options/rt:next-hop-list/"
+ "rt:next-hop-list/rt:next-hop" {
description
"Output MPLS augmentation for the 'active-route' action
statement.";
uses nhlfe-multiple-contents;
}
}
<CODE ENDS>
Figure 4: MPLS base Base YANG module. Module
3. IANA Considerations
This document registers the following URIs URI in the 'ns' sub-registry "ns" subregistry of
the IETF "IETF XML registry Registry" [RFC3688]. Following the format in
[RFC3688], the following registration is requested to be made.
URI: urn:ietf:params:xml:ns:yang:ietf-mpls
Registrant Contact: The MPLS WG of the IETF.
XML: N/A, N/A; the requested URI is an XML namespace.
This document registers a the following YANG module in the YANG "YANG Module Names
Names" registry [RFC6020].
name:
Name: ietf-mpls
namespace:
Namespace: urn:ietf:params:xml:ns:yang:ietf-mpls
prefix:
Prefix: mpls
//
Reference: RFC Ed.: replace XXXX with RFC number and remove this note
reference: RFCXXXX 8960
4. Security Considerations
The YANG module specified in this document define 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 NETCONF access control model 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 this 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:
"/rt:routing/mpls:mpls/mpls:label-blocks": there
There are data nodes under this path that are writeable writable, such as 'start-label'
"start-label" and 'end-label'. "end-label". Write operations to those data npdes
nodes may cause disruptive action result in disruption to existing traffic.
Some of the readable data nodes in these this 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/rt:routes/rt:route/rt:next-hop/rt:next-
hop-options/rt:next-hop-list/rt:next-hop-list/rt:next-hop"
"/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"
and
"/rt:routing/rt:ribs/rt:rib/rt:active-route/rt:output/rt:route/
rt:next-hop/rt:next-hop-options/rt:simple-next-hop": these "/rt:routing/rt:ribs/rt:rib/rt:active-
route/rt:output/rt:route/rt:next-hop/rt:next-hop-options/
rt:simple-next-hop":
These two paths are augmented by additional MPLS leaf(s) leafs defined in
this model. Access to this information may disclose the next-hop or path per
information for the prefix route and/or other information.
Some of the RPC operations in this YANG module may be considered
sensitive or vulnerable in some network environments. It is thus
important to control access to these operations. These are the
operations and their sensitivity/vulnerability:
"/rt:routing/rt:ribs/rt:rib/rt:active-route/rt:input" and
"/rt:routing/rt:ribs/rt:rib/rt:active-route/rt:output/rt:route":
these
These two paths are augmented by additional MPLS data node(s) nodes that
are defined in this model. Access to those path(s) may paths may disclose
information about per prefix route per-prefix routes and/or other information and that information; such
disclosure may be further used for further attack(s). attacks.
The security considerations spelled out in [RFC3031] and [RFC3032]
apply for this document as well.
8.
5. References
8.1.
5.1. Normative References
[RFC3032] Rosen, E., Tappan, D., Fedorkow, G., Rekhter, Y.,
Farinacci, D., Li, T., and A. Conta, "MPLS Label Stack
Encoding", RFC 3032, DOI 10.17487/RFC3032, January 2001,
<https://www.rfc-editor.org/info/rfc3032>.
[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>.
[RFC8294] Liu, X., Qu, Y., Lindem, A., Hopps, C., and L. Berger,
"Common YANG Data Types for the Routing Area", RFC 8294,
DOI 10.17487/RFC8294, December 2017,
<https://www.rfc-editor.org/info/rfc8294>.
[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>.
[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>.
[RFC8402] Filsfils, C., Ed., Previdi, S., Ed., Ginsberg, L.,
Decraene, B., Litkowski, S., and R. Shakir, "Segment
Routing Architecture", RFC 8402, DOI 10.17487/RFC8402,
July 2018, <https://www.rfc-editor.org/info/rfc8402>.
[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>.
8.2.
5.2. Informative References
[RFC3031] Rosen, E., Viswanathan, A., and R. Callon, "Multiprotocol
Label Switching Architecture", RFC 3031,
DOI 10.17487/RFC3031, January 2001,
<https://www.rfc-editor.org/info/rfc3031>.
[RFC4090] Pan, P., Ed., Swallow, G., Ed., and A. Atlas, Ed., "Fast
Reroute Extensions to RSVP-TE for LSP Tunnels", RFC 4090,
DOI 10.17487/RFC4090, May 2005,
<https://www.rfc-editor.org/info/rfc4090>.
[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>.
[RFC7424] Krishnan, R., Yong, L., Ghanwani, A., So, N., and B.
Khasnabish, "Mechanisms for Optimizing Link Aggregation
Group (LAG) and Equal-Cost Multipath (ECMP) Component Link
Utilization in Networks", RFC 7424, DOI 10.17487/RFC7424,
January 2015, <https://www.rfc-editor.org/info/rfc7424>.
6.
[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>.
Appendix A. Data Tree Instance Example
A simple network setup is shown in Figure 5. R1 runs the ISIS IS-IS
routing protocol, protocol and learns reachability about the reachability of two IPv4 prefixes:
P1:
prefixes (P1: 198.51.100.1/32 and P2: 198.51.100.1/32, 198.51.100.2/32) and two IPv6
prefixes
P3: 2001:db8:0:10::1/64 (P3: 2001:db8:0:10::1/128 and P4: 2001:db8:0:10::1/64. 2001:db8:0:10::2/128). We
also assume that R1 learns about local and remote MPLS label bindings
for each prefix using ISIS (e.g. IS-IS (e.g., using Segment-Routing Segment Routing (SR)
extensions).
State on R1:
============
IPv4 Prefix MPLS Label
P1: 198.51.100.1/32 16001
P2: 198.51.100.2/32 16002
IPv6 Prefix MPLS Label
P3: 2001:db8:0:10::1/64 2001:db8:0:10::1/128 16003
P4: 2001:db8:0:10::2/64 2001:db8:0:10::2/128 16004
RSVP MPLS LSPv4-Tunnel:
Source: 198.51.100.3
Destination: 198.51.100.4
Tunnel-ID: 10
LSP-ID: 1
192.0.2.5/30
2001:db8:0:1::1/64
eth0
+---
/
+-----+
| R1 |
+-----+
\
+---
eth1
192.0.2.13/30
2001:db8:0:2::1/64
Figure 5: Example of network configuration. Network Configuration
The instance data tree could then be illustrated as follows: shown in
Figure 6, using JSON format [RFC7951]:
{
"ietf-routing:routing":{
"ribs":{
"rib":[
{
"name":"RIB-V4",
"address-family":
"ietf-ipv4-unicast-routing:v4ur:ipv4-unicast",
"routes":{
"route":[
{
"next-hop":{
"outgoing-interface":"eth0",
"ietf-mpls:mpls-label-stack":{
"entry":[
{
"id":1,
"label":16001,
"ttl":255
}
]
},
"ietf-ipv4-unicast-routing:next-hop-address":
"192.0.2.5"
},
"source-protocol":"isis:isis",
"source-protocol":"ietf-isis:isis",
"ietf-mpls:mpls-enabled":true,
"ietf-mpls:mpls-local-label":16001,
"ietf-ipv4-unicast-routing:destination-prefix":
"198.51.100.1/32",
"ietf-mpls:route-context":"SID-IDX:1"
},
{
"next-hop":{
"next-hop-list":{
"next-hop":[
{
"outgoing-interface":"eth0",
"ietf-mpls:index":"1",
"ietf-mpls:backup-index":"2",
"ietf-mpls:role":"primary-and-backup",
"ietf-mpls:mpls-label-stack":{
"entry":[
{
"id":1,
"label":16002,
"ttl":255
}
]
},
"ietf-ipv4-unicast-routing:address":"192.0.2.5"
"ietf-ipv4-unicast-routing:address":
"192.0.2.5"
},
{
"outgoing-interface":"eth1",
"ietf-mpls:index":"2",
"ietf-mpls:backup-index":"1",
"ietf-mpls:role":"primary-and-backup",
"ietf-mpls:mpls-label-stack":{
"entry":[
{
"id":1,
"label":16002,
"ttl":255
}
]
},
"ietf-ipv4-unicast-routing:address":"192.0.2.13"
"ietf-ipv4-unicast-routing:address":
"192.0.2.13"
}
]
}
},
"source-protocol":"isis:isis",
"source-protocol":"ietf-isis:isis",
"ietf-mpls:mpls-enabled":true,
"ietf-mpls:mpls-local-label":16002,
"ietf-ipv4-unicast-routing:destination-prefix":
"198.51.100.2/32",
"ietf-mpls:route-context":"SID-IDX:2"
}
]
}
},
{
"name":"RIB-V6",
"address-family":
"ietf-ipv6-unicast-routing:v6ur:ipv6-unicast",
"routes":{
"route":[
{
"next-hop":{
"outgoing-interface":"eth0",
"ietf-mpls:mpls-label-stack":{
"entry":[
{
"id":1,
"label":16003,
"ttl":255
}
]
},
"ietf-ipv6-unicast-routing:next-hop-address":
"2001:db8:0:1::1"
},
"source-protocol":"isis:isis",
"source-protocol":"ietf-isis:isis",
"ietf-mpls:mpls-enabled":true,
"ietf-mpls:mpls-local-label":16001,
"ietf-mpls:mpls-local-label":16003,
"ietf-ipv6-unicast-routing:destination-prefix":
"2001:db8:0:10::1/6",
"ietf-mpls:route-context":"SID-IDX:1"
"2001:db8:0:10::1/128",
"ietf-mpls:route-context":"SID-IDX:3"
},
{
"next-hop":{
"next-hop-list":{
"next-hop":[
{
"outgoing-interface":"eth0",
"ietf-mpls:index":"1",
"ietf-mpls:backup-index":"2",
"ietf-mpls:role":"primary-and-backup",
"ietf-mpls:mpls-label-stack":{
"entry":[
{
"id":1,
"label":16004,
"ttl":255
}
]
},
"ietf-ipv6-unicast-routing:address":
"2001:db8:0:1::1"
},
{
"outgoing-interface":"eth1",
"ietf-mpls:index":"2",
"ietf-mpls:backup-index":"1",
"ietf-mpls:role":"primary-and-backup",
"ietf-mpls:mpls-label-stack":{
"entry":[
{
"id":1,
"label":16004,
"ttl":255
}
]
},
"ietf-ipv6-unicast-routing:address":
"2001:db8:0:2::1"
}
]
}
},
"source-protocol":"isis:isis",
"source-protocol":"ietf-isis:isis",
"ietf-mpls:mpls-enabled":true,
"ietf-mpls:mpls-local-label":16004,
"ietf-ipv6-unicast-routing:destination-prefix":
"2001:db8:0:10::2/64",
"ietf-mpls:route-context":"SID-IDX:2"
"2001:db8:0:10::2/128",
"ietf-mpls:route-context":"SID-IDX:4"
}
]
}
},
{
"name":"RIB-MPLS",
"address-family":"ietf-mpls:mpls:mpls",
"routes":{
"route":[
{
"next-hop":{
"outgoing-interface":"eth0",
"ietf-mpls:mpls-label-stack":{
"entry":[
{
"id":1,
"label":24002,
"ttl":255
}
]
},
"ietf-ipv4-unicast-routing:next-hop-address":
"192.0.2.5"
},
"source-protocol":"rsvp:rsvp",
"source-protocol":"ietf-rsvp:rsvp",
"ietf-mpls:mpls-enabled":true,
"ietf-mpls:mpls-local-label":24001,
"ietf-mpls:destination-prefix":"24001",
"ietf-mpls:route-context":
"RSVP Src:198.51.100.3,Dst:198.51.100.4,T:10,L:1"
}
}
]
}
}
]
},
"ietf-mpls:mpls":{
"mpls-label-blocks":{
"mpls-label-block":[
{
"index":"mpls-srgb-label-block",
"start-label":16000,
"end-label":16500,
"block-allocation-mode":"mpls:label-block-alloc-mode-manager"
"block-allocation-mode":
"ietf-mpls:label-block-alloc-mode-manager"
}
]
},
"interfaces":{
"interface":[
{
"name":"eth0",
"mpls-enabled":true,
"maximum-labeled-packet":1488
},
{
"name":"eth1",
"mpls-enabled":true,
"maximum-labeled-packet":1488
}
]
}
}
}
}
Figure 6: Foo bar.
5. Acknowledgement Instance Data Tree Example
Acknowledgments
The authors would like to thank Xia Chen for her contributions to the
early draft revisions of this document.
7.
Contributors
Igor Bryskin
Huawei Technologies
email:
Email: i_bryskin@yahoo.com
Himanshu Shah
Ciena
email:
Email: hshah@ciena.com
Authors' Addresses
Tarek Saad
Juniper Networks
Email: tsaad@juniper.net
Kamran Raza
Cisco Systems Inc Systems, Inc.
Email: skraza@cisco.com
Rakesh Gandhi
Cisco Systems Inc Systems, Inc.
Email: rgandhi@cisco.com
Xufeng Liu
Volta Networks
Email: xufeng.liu.ietf@gmail.com
Vishnu Pavan Beeram
Juniper Networks
Email: vbeeram@juniper.net