MPLS Working Group K. Raza
Internet-Draft Cisco Systems, Inc.
Intended status: Standards Track X. Liu
Expires: January 7, 2016 Ericsson
S. Esale
Juniper Networks
X. Chen
Huawei Technologies
H. Shah
Ciena Corporation
R. Rahman
R. Asati
N. Kumar
Cisco Systems, Inc.
J. Tantsura
Ericsson
L. Andersson
Huawei Technologies
M. Bocci
Alcatel-Lucent
V. Beeram
Juniper Networks
S. Litkowski
Orange
July 6, 2015
YANG Data Model for MPLS LDP and mLDP
draft-raza-mpls-ldp-mldp-yang-01
Abstract
This document describes a YANG data model for Multi-Protocol Label
Switching (MPLS) Label Distribution Protocol (LDP) and Multipoint LDP
(mLDP).
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
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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 January 7, 2016.
Copyright Notice
Copyright (c) 2015 IETF Trust and the persons identified as the
document authors. All rights reserved.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Specification of Requirements . . . . . . . . . . . . . . . . 3
3. LDP YANG Model . . . . . . . . . . . . . . . . . . . . . . . 3
3.1. Overview . . . . . . . . . . . . . . . . . . . . . . . . 4
3.2. Configuration . . . . . . . . . . . . . . . . . . . . . . 5
3.2.1. Configuration Hierarchy . . . . . . . . . . . . . . . 8
3.2.2. All-VRFs Configuration . . . . . . . . . . . . . . . 11
3.3. Operational State . . . . . . . . . . . . . . . . . . . . 11
3.4. Notifications . . . . . . . . . . . . . . . . . . . . . . 11
3.5. Actions . . . . . . . . . . . . . . . . . . . . . . . . . 12
4. mLDP YANG Model . . . . . . . . . . . . . . . . . . . . . . . 13
4.1. Overview . . . . . . . . . . . . . . . . . . . . . . . . 13
4.2. Configuration . . . . . . . . . . . . . . . . . . . . . . 14
4.2.1. Configuration Hierarchy . . . . . . . . . . . . . . . 14
4.2.2. mldp container . . . . . . . . . . . . . . . . . . . 16
4.2.3. Leveraging LDP containers . . . . . . . . . . . . . . 16
4.2.4. YANG tree . . . . . . . . . . . . . . . . . . . . . . 17
4.3. Operational State . . . . . . . . . . . . . . . . . . . . 19
4.4. Notifications . . . . . . . . . . . . . . . . . . . . . . 19
4.5. Actions . . . . . . . . . . . . . . . . . . . . . . . . . 20
5. YANG Specification . . . . . . . . . . . . . . . . . . . . . 20
6. Security Considerations . . . . . . . . . . . . . . . . . . . 54
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 54
8. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 54
9. References . . . . . . . . . . . . . . . . . . . . . . . . . 55
9.1. Normative References . . . . . . . . . . . . . . . . . . 55
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9.2. Informative References . . . . . . . . . . . . . . . . . 56
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 57
1. Introduction
The Network Configuration Protocol (NETCONF) [RFC6241] is a network
management protocol that defines mechanisms to manage network
devices. YANG [RFC6020] is a modular language that represents data
structures in an XML tree format, and is used as a data modelling
language for the NETCONF.
This document introduces a YANG data model for MPLS Label
Distribution Protocol (LDP) [RFC5036] and Multipoint LDP (mLDP)
[RFC6388]. For LDP, it also covers LDP IPv6 [RFC7552] and LDP
capabilities [RFC5561].
The data model is defined for following constructs that are used for
managing the protocol:
o Configuration
o Operational State
o Executables (Actions)
o Notifications
Given mLDP tight coupling with LDP, mLDP model is defined under LDP
tree. The document is organized to first define the data model for
the configuration, operational state, actions and notifications of
LDP, followed by mLDP model in the same order.
2. Specification of Requirements
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 [RFC2119].
In this document, the word "IP" is used to refer to both IPv4 and
IPv6, unless otherwise explicitly stated. For example, "IP address
family" means and be read as "IPv4 and/or IPv6 address family"
3. LDP YANG Model
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3.1. Overview
The LDP/mLDP Yang model is defined under "ietf-mpls-ldp" module and
augments "routing-protocol" list in ietf-routing module
[I-D.ietf-netmod-routing-cfg] with LDP and mLDP specific parameters.
[Ed note: This model will be aligned with MPLS as and when a base
tree for MPLS is defined and available].
There are four containers in LDP module as follows:
o Read-Write parameters (for configuration)
o Read-only parameters (for operational state)
o Notifications (for events)
o RPCs (for executing commands to perform some action)
Before going into data model details, it is important to take note of
the following points:
o This module aims to address only the core LDP/mLDP parameters as
per RFC specification, as well as some widely used and deployed
non-RFC features. Any vendor specific feature should be defined
in a vendor-specific augmentation of this model.
o Multi-topology LDP [RFC7307] and Multi-topology mLDP
[I-D.iwijnand-mpls-mldp-multi-topology] are beyond the scope of
this document.
o This module does not cover any applications running on top of LDP
and mLDP, nor does it cover any OAM procedures for LDP and mLDP.
o This model is a VRF-centric model and hence falls under a routing-
instance.
o This model assumes platform-wide label space (i.e. label space Id
of zero).
o A "routing-instance" refers to a VRF instance within the scope of
this model.
o This model supports two address-families, namely "ipv4" and
"ipv6".
o The label and neighbor policies and filters are typically defined
using a prefix-list. The prefix-list is referenced from routing-
policy model as defined in [I-D.shaikh-rtgwg-policy-model].
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o The use of grouping (templates) for bundling and grouping the
configuration items is not employed in current model, and is a
subject for consideration in future.
A graphical representation of LDP YANG data model is presented in
Figure 2, Figure 4, Figure 5, and Figure 6. Whereas, the actual
model definition in YANG is captured in Section 5.
3.2. Configuration
This specification defines the configuration parameters for base LDP
as defined in [RFC5036] and LDP IPv6 [RFC7552]. Moreover, it
incorporates provisions to enable LDP Capabilities [RFC5561], and
defines some of the most significant and commonly used capabilities
such as Typed Wildcard FEC [RFC5918], End-of-LIB [RFC5919], and LDP
Upstream Label Assignment [RFC6389].
This specification supports VRF-centric configuration. For
implementations that support protocol-centric configuration, with
provision for inheritance and items that apply to all vrfs, we
recommend an augmentation of this model such that any protocol-
centric or all-vrf configuration is defined under their designated
containers within the standard routing-instance (please see section
Section 3.2.2)
module: ietf-mpls-ldp
+-- routing
+-- routing-instance [name]
+-- routing-protocols
+-- routing-protocol [name]
+-- mpls-ldp
.
.
Figure 1
Given the configuration hierarchy, the model allows inheritance such
that an item in a child tree is able to derive value from a similar
or related item in one of the parent. For instance, hello holdtime
can be configured per-VRF or per-VRF-interface, thus allowing
inheritance as well flexibility to override with a different value on
any child level.
Following is a simplified graphical representation of the data model
for LDP configuration.
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module: ietf-mpls-ldp
augment /rt:routing/rt:routing-instance/rt:routing-protocols/rt:routing-protocol:
+--rw mpls-ldp
+--rw lsr-id? yang:dotted-quad
+--rw capability
| +--rw end-of-lib {capability-end-of-lib}?
| | +--rw enable? boolean
| +--rw typed-wildcard-fec {capability-typed-wildcard-fec}?
| | +--rw enable? boolean
| +--rw upstream-label-assignment {capability-upstream-label-assignment}?
| +--rw enable? boolean
+--rw graceful-restart
| +--rw enable? boolean
| +--rw helper-enable? boolean {graceful-restart-helper-mode}?
| +--rw reconnect-time? uint16
| +--rw recovery-time? uint16
| +--rw forwarding-holdtime? uint16
+--rw igp-synchronization-delay? uint16
+--rw nonstop-routing? boolean
+--rw address-family* [af]
| +--rw af address-family-type
| +--rw enable? boolean
| +--rw label-policy
| | +--rw independent-mode
| | | +--rw assign {policy-label-assignment-config}?
| | | | +--rw (prefix-option)?
| | | | +--:(prefix-list)
| | | | | +--rw prefix-list? prefix-list-ref
| | | | +--:(host-routes-only)
| | | | +--rw host-routes-only? boolean
| | | +--rw advertise
| | | | +--rw explicit-null!
| | | | | +--rw prefix-list? prefix-list-ref
| | | | +--rw prefix-list? prefix-list-ref
| | | +--rw accept
| | | +--rw prefix-list? prefix-list-ref
| | +--rw ordered-mode {policy-ordered-label-config}?
| | +--rw egress-lsr
| | | +--rw prefix-list? prefix-list-ref
| | +--rw advertise
| | | +--rw prefix-list? prefix-list-ref
| | +--rw accept
| | +--rw prefix-list? prefix-list-ref
| +--rw ipv4
| | +--rw transport-address? inet:ipv4-address
| +--rw ipv6
| +--rw transport-address? inet:ipv6-address
+--rw discovery
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| +--rw interfaces
| | +--rw hello-holdtime? uint16
| | +--rw hello-interval? uint16
| | +--rw interface* [interface]
| | +--rw interface if:interface-ref
| | +--rw hello-holdtime? uint16
| | +--rw hello-interval? uint16
| | +--rw igp-synchronization-delay? uint16 {per-interface-timer-config}?
| | +--rw address-family* [af]
| | +--rw af address-family-type
| | +--rw enable? boolean
| | +--rw ipv4
| | | +--rw transport-address? union
| | +--rw ipv6
| | +--rw transport-address? union
| +--rw targeted
| +--rw hello-holdtime? uint16
| +--rw hello-interval? uint16
| +--rw hello-accept {policy-extended-discovery-config}?
| | +--rw enable? boolean
| | +--rw peer-list? peer-list-ref
| +--rw address-family
| +--rw ipv4
| | +--rw target* [address]
| | +--rw address inet:ipv4-address
| | +--rw enable? boolean
| +--rw ipv6
| +--rw target* [address]
| +--rw address inet:ipv6-address
| +--rw enable? boolean
+--rw forwarding-nexthop {forwarding-nexthop-config}?
| +--rw interfaces
| +--rw interface* [interface]
| +--rw interface if:interface-ref
| +--rw address-family* [af]
| +--rw af address-family-type
| +--rw ldp-disable? boolean
+--rw neighbors
+--rw md5-password? string
+--rw session-ka-holdtime? uint16
+--rw session-ka-interval? uint16
+--rw session-downstream-on-demand {session-downstream-on-demand-config}?
| +--rw enable? boolean
| +--rw peer-list? peer-list-ref
+--rw session-protection {session-protection}?
| +--rw enable? boolean
| +--rw duration? union
| +--rw peer-list? peer-list-ref
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+--rw neighbor* [lsr-id]
+--rw lsr-id union
+--rw admin-down? boolean
+--rw capability
| +--rw ...
+--rw md5-password? string
+--rw graceful-restart
| +--rw enable? boolean
| +--rw reconnect-time? uint16
| +--rw recovery-time? uint16
+--rw session-ka-holdtime? uint16
+--rw session-ka-interval? uint16
+--rw session-protection {session-protection}?
| +--rw enable? boolean
| +--rw duration? union
+--rw address-family
+--rw ipv4
| +--rw label-policy
| +--rw advertise
| | +--rw prefix-list? prefix-list-ref
| +--rw accept
| +--rw prefix-list? prefix-list-ref
+--rw ipv6
+--rw label-policy
+--rw advertise
| +--rw prefix-list? prefix-list-ref
+--rw accept
+--rw prefix-list? prefix-list-ref
Figure 2
3.2.1. Configuration Hierarchy
The LDP configuration container is logically divided into following
high level config areas:
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Per-VRF parameters
o Global parameters
o Per-address-family parameters
o LDP Capabilities parameters
o Hello Discovery parameters
- interfaces
- Per-interface:
Global
Per-address-family
- targeted
- Per-target
o Neighbor parameters
- Global
- Per-neighbor
Per-address-family
Capabilities parameters
o Forwarding parameters
Figure 3
Following subsections briefly explain these configuration areas.
3.2.1.1. Per-VRF parameters
LDP module resides under a routing-instance and the scope of any LDP
configuration defined under this tree is per routing-instance (per-
VRF). This configuration is further divided into sub categories as
follows.
3.2.1.1.1. Per-VRF global parameters
There are configuration items that are available directly under a VRF
instance and do not fall under any other sub tree. Example of such a
parameter is LDP lsr-id which is typically configured per VRF.
3.2.1.1.2. Per-VRF Per-Address-Family parameters
Any LDP configuration parameter related to IP address family (AF)
whose scope is VRF wide is configured under this tree. The examples
of per-AF parameters include enabling the AF, prefix-list based label
policies, and LDP transport address.
3.2.1.1.3. Per-VRF Capabilities parameters
This container holds the LDP capabilities that are to be enabled for
certain features. By default, an LDP capability is disabled unless
explicitly enabled. These capabilities are typically used to
negotiate with LDP peer(s) the support/non-support related to a
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feature and its parameters. The scope of a capability enabled under
this container applies to all LDP neighbors in the given VRF
instance. There is also a per-neighbor level capability container
that is provided to override a capability that is enabled/specified
at VRF level.
3.2.1.1.4. Per-VRF Hello Discovery parameters
This container is used to hold LDP configuration related to Hello and
discovery process for both basic (link) and extended (targeted)
discovery.
The "interfaces" is a container to configure parameters related to
VRF interfaces. There are parameters that apply to all interfaces
(such as hello timers), as well as parameters that can be configured
per-interface. Hence, an interface list is defined under
"interfaces" container. The model defines parameters to configure
per-interface non AF related items, as well as per-interface per-AF
items. The example of former is interface hello timers, and example
of latter is enabling hellos for a given AF under an interface.
The "targeted" container under a VRF instance allows to configure LDP
targeted discovery related parameters. Within this container, the
"target" list provides a mean to configure multiple target addresses
to perform extended discovery to a specific destination target, as
well as to fine tune parameters per-target.
3.2.1.1.5. Per-VRF Neighbor parameters
This container is used to hold LDP configuration related to LDP
neighbors (i.e. peers) under a VRF instance. This container allows
to configure parameters that either apply on VRF's all neighbors or a
subset (peer-list) of VRF neighbors. The example of such parameters
include authentication password, session KA timers etc. Moroever,
the model also allows per-neighbor parameter tuning by specifying a
"neighbor" list under the "neighbors" container. A neighbor is
uniquely identified using its LSR Id and hence lsr-id is the key for
neighbor list
Like per-interface parameters, some per-neighbor parameters are AF-
agnostic (i.e. either non AF related or apply to both IP address
families), and some that belong to an AF. The example of former is
per-neighbor password configuration, whereas the example of latter is
prefix-list based label policies (inbound and outbound) that apply to
a given neighbor.
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3.2.1.1.6. Per-VRF Forwarding parameters
This container is used to hold configuration used to control LDP
forwarding behavior under a VRF instance. One example of a
configuration under this container is when a user wishes to enable
neighbor discovery on an interface but wishes to disable use of the
same interface as forwarding nexthop. This example configuration
makes sense only when there are more than one LDP enabled interfaces
towards the neighbor.
3.2.2. All-VRFs Configuration
TODO.
3.3. Operational State
Operational state of LDP can be queried and obtained from this read-
only container "mpls-ldp" which is augmented from "routing-state" of
a routing-protocol (/rt:routing-state/rt:routing-instance/
rt:routing-protocols/rt:routing-protocol).
Following is a simplified graphical representation of the data model
for LDP operational state.
module: ietf-mpls-ldp
augment /rt:routing-state/rt:routing-instance/rt:routing-protocols/
rt:routing-protocol:
+--ro mpls-ldp
+-- ...
+-- ...
[Ed note: TODO (later revision)]
Figure 4
3.4. Notifications
This model defines a list of notifications to inform client of
important events detected during the protocol operation. These
events include events related to changes in the operational state of
an LDP neighbor, hello adjacency, and FEC etc. It is to be noted
that an LDP FEC is treated as operational (up) as long as it has
atleast 1 NHLFE with outgoing label.
Following is a simplified graphical representation of the data model
for LDP notifications.
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module: ietf-mpls-ldp
notifications:
+---n mpls-ldp-neighbor-event
| +--ro event-type? oper-status-event-type
| +--ro routing-instance-ref? rt:routing-instance-ref
| +--ro ldp-protocol-name? leafref
| +--ro neighbor-ref? leafref
+---n mpls-ldp-adjacency-event
| +--ro event-type? oper-status-event-type
| +--ro routing-instance-ref? rt:routing-instance-ref
| +--ro ldp-protocol-name? leafref
| +--ro (adjacency-type)?
| +--:(targeted)
| | +--ro targeted
| | +--ro target-address? inet:ip-address
| +--:(link)
| +--ro link
| +--ro next-hop-interface? if:interface-ref
| +--ro next-hop-address? inet:ip-address
+---n mpls-ldp-fec-event
+--ro event-type? oper-status-event-type
+--ro routing-instance-ref? rt:routing-instance-ref
+--ro ldp-protocol-name? leafref
+--ro prefix? inet:ip-prefix
Figure 5
3.5. Actions
This model defines a list of rpcs that allow performing an action or
executing a command on the protocol. For example, it allows to clear
(reset) LDP neighbors, hello-adjacencies, and statistics. The model
makes an effort to provide different level of control so that a user
is able to either clear all, or clear all of a given type, or clear a
specific entity.
Following is a simplified graphical representation of the data model
for LDP actions.
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module: ietf-mpls-ldp
+---x mpls-ldp-clear-neighbor
| +--ro input
| +--ro routing-instance-ref? rt:routing-instance-ref
| +--ro ldp-protocol-name? leafref
| +--ro lsr-id? union
+---x mpls-ldp-clear-adjacency
| +--ro input
| +--ro routing-instance-ref? rt:routing-instance-ref
| +--ro ldp-protocol-name? leafref
| +--ro adjacency
| +--ro (adjacency-type)?
| +--:(targeted)
| | +--ro targeted!
| | +--ro target-address? inet:ip-address
| +--:(link)
| +--ro link!
| +--ro next-hop-interface? if:interface-ref
| +--ro next-hop-address? inet:ip-address
+---x mpls-ldp-clear-neighbor-statistics
+--ro input
+--ro routing-instance-ref? rt:routing-instance-ref
+--ro ldp-protocol-name? leafref
+--ro lsr-id? union
Figure 6
4. mLDP YANG Model
4.1. Overview
Due to tight dependency of mLDP on LDP, mLDP model builds on top of
LDP model defined earlier in the document. Following are the main
mLDP areas and documents that are within the scope of this model:
o mLDP Base Specifiction [RFC6388]
o mLDP Recursive FEC [RFC6512]
o Targeted mLDP [RFC7060]
o mLDP Fast-Reroute (FRR)
* Node Protection [I-D.ietf-mpls-mldp-node-protection]
* Multicast-only
o Hub-and-Spoke Multipoint LSPs [RFC7140]
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o mLDP Inband Signaling [RFC6826] (future revision)
o mLDP Inband Signaling with Wildcards [RFC7438] (future revision)
o Configured LSPs (manually privisioned)
[Ed Note: Some of the topics in the above list are to be addressed/
added in later revision of this document].
4.2. Configuration
4.2.1. Configuration Hierarchy
In terms of overall configuration layout, following figure highlights
extensions to LDP configuration model to incorporate mLDP:
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+-- mpls-ldp
+-- ...
+-- ...
+-- mldp
| +-- ...
| +-- ...
| +-- address-family* [af]
| +-- af
| +-- ...
| +-- ...
+-- capability
| +-- ...
| +-- ...
| +-- mldp
| +-- ...
| +-- ...
+-- discovery
| +-- ...
| +-- ...
+-- forwarding-nexthop
| +-- interfaces
| +-- interface* [interface]
| +-- interface
| +-- address-family* [af]
| +-- af
| +-- ...
| +-- mldp-disable
+-- neighbors
+-- ...
+-- ...
+-- neighbor* [lsr-id]
+-- ...
+-- ...
+-- capability
+-- ...
+-- ...
+-- mldp
+-- ...
+-- ...
Figure 7
From above hierarchy, we can cateogrize mLDP configuration paramters
into two types:
o Parameters that leverage/extend LDP containers and parameters
o Parameters that are mLDP specific
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Following subsections first describe mLDP specific configuration
parameters, followed by those leveraging LDP.
4.2.2. mldp container
mldp container resides directly under "mpls-ldp" and holds the
configuration related to items that are mLDP specific. The main
items under this container are:
o mLDP enabling: To enable mLDP under a (VRF) routing instance, mldp
container is enabled under LDP. Given that mLDP requires LDP
signalling, it is not sensible to allow disabling LDP control
plane under a (VRF) routing-instance while requiring mLDP to be
enabled for the same. However, if a user wishes only to allow
signalling for multipoint FECs on an LDP/mLDP enabled VRF
instance, he/she can use LDP label-policies to disable unicast
FECs under the VRF.
o mLDP per-AF features: mLDP manages its own list of IP address-
families and the features enabled underneath. The per-AF mLDP
configuration items include:
* Multicast-only FRR: This enables Multicast-only FRR
functionality for a given AF under mLDP. The feature allows
route-policy to be configured for finer control/applicability
of the feature.
* Recursive FEC: The recursive-fec feature [RFC6512] can be
enabled per AF with a route-policy.
* Configured LSPs: To provision multipoint LSP manually, a
container is provided per-AF under LDP. The configuration is
flexible and allows a user to specify MP LSPs of type p2mp or
mp2mp with IPv4 or IPv6 root address(es) by using either LSP-Id
or (S,G).
Targeted mLDP feature specification [RFC7060] do not require any mLDP
specific configuration. It, however, requires LDP upstream-label-
assignment capability to be enabled.
4.2.3. Leveraging LDP containers
mLDP configuration model leverages following configuration areas and
containers that are already defined for LDP:
o Capabilities: A new container "mldp" is defined under Capabilities
container. This new container specifies any mLDP specific
capabilities and their parameters. Moreover, a new "mldp"
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container is also added under per-neighbor capability container to
override/control mLDP specific capabilities on a neighbor level.
In the scope of this document, the most important capabilities
related to mLDP are p2mp, mp2mp, make-before-break, hub-and-spoke,
and node-protection.
o Discovery and Neighbor: mLDP requires LDP discovery and neighbor
procedures to form mLDP peering. A neighbor is treated as mLDP
neighbor only when either P2MP or MP2MP capabilities have been
successfully exchanged with the peer. If a user wish to
selectively enable or disable mLDP with a mLDP-enabled peer, he/
she may use per-neighbor mLDP capabilities configuration. [Ed
Note: The option to control mLDP enabling/disabling on a neighbor-
list is being explored for future ]. In most common deployments,
it is desirable to disable mLDP (capabilities announcements) on a
targeted-only LDP session, where targeted-only session is the one
whose discovery sources are targeted only. In future revision, a
configuration option for this support will also be provided
[TODO].
o Forwarding: By default, mLDP is allowed to select any of the LDP
enabled interface as a downstream interface towards a nexthop
(LDP/mLDP peer) for MP LSP programming. However, a configuration
option is provided to allow mLDP to exclude a given interface from
such a selection. Note that such a configuration option will be
useful only when there are more than one interfaces available for
the downstream selection.
4.2.4. YANG tree
The following figure captures the YANG tree for mLDP configuration.
The figure has been simplified to display only mLDP items and not LDP
items to keep the focus.
module: ietf-mpls-ldp
augment /rt:routing/rt:routing-instance/rt:routing-protocols/rt:routing-protocol:
+--rw mpls-ldp
+--rw mldp {mldp}?
| +--rw enable? boolean
| +--rw address-family* [af]
| +--rw af address-family-type
| +--rw multicast-only-frr {mldp-mofrr}?
| +--rw recursive-fec
| +--rw configured-lsps
| +--rw p2mp
| | +--rw roots-ipv4
| | | +--rw root* [root-addr]
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| | | +--rw root-addr inet:ipv4-address
| | | +--rw lsp* [lsp-id source-addr group-addr]
| | | +--rw lsp-id uint16
| | | +--rw source-addr inet:ipv4-address-no-zone
| | | +--rw group-addr inet:ipv4-address-no-zone
| | +--rw roots-ipv6
| | +--rw root* [root-addr]
| | +--rw root-addr inet:ipv6-address
| | +--rw lsp* [lsp-id source-addr group-addr]
| | +--rw lsp-id uint16
| | +--rw source-addr inet:ipv6-address-no-zone
| | +--rw group-addr inet:ipv6-address-no-zone
| +--rw mp2mp
| +--rw roots-ipv4
| | +--rw root* [root-addr]
| | +--rw root-addr inet:ipv4-address
| | +--rw lsp* [lsp-id source-addr group-addr]
| | +--rw lsp-id uint16
| | +--rw source-addr inet:ipv4-address-no-zone
| | +--rw group-addr inet:ipv4-address-no-zone
| +--rw roots-ipv6
| +--rw root* [root-addr]
| +--rw root-addr inet:ipv6-address
| +--rw lsp* [lsp-id source-addr group-addr]
| +--rw lsp-id uint16
| +--rw source-addr inet:ipv6-address-no-zone
| +--rw group-addr inet:ipv6-address-no-zone
+--rw capability
| +--rw mldp {mldp}?
| +--rw p2mp
| | +--rw enable? boolean
| +--rw mp2mp
| | +--rw enable? boolean
| +--rw make-before-break
| | +--rw enable? boolean
| | +--rw switchover-delay? uint16
| | +--rw timeout? uint16
| +--rw hub-and-spoke {capability-mldp-hsmp}?
| | +--rw enable? boolean
| +--rw node-protection {capability-mldp-node-protection}?
| +--rw plr? boolean
| +--rw merge-point
| +--rw enable? boolean
| +--rw targeted-session-teardown-delay? uint16
+--rw forwarding-nexthop {forwarding-nexthop-config}?
| +--rw interfaces
| +--rw interface* [interface]
| +--rw interface if:interface-ref
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| +--rw address-family* [af]
| +--rw af address-family-type
| +--rw mldp-disable? boolean {mldp}?
+--rw neighbors
+--rw neighbor* [lsr-id]
+--rw lsr-id union
+--rw capability
+--rw mldp {mldp}?
+--rw p2mp
| +--rw enable? boolean
+--rw mp2mp
| +--rw enable? boolean
+--rw make-before-break
| +--rw enable? boolean
| +--rw switchover-delay? uint16
| +--rw timeout? uint16
+--rw hub-and-spoke {capability-mldp-hsmp}?
| +--rw enable? boolean
+--rw node-protection {capability-mldp-node-protection}?
+--rw plr? boolean
+--rw merge-point
+--rw enable? boolean
+--rw targeted-session-teardown-delay? uint16
Figure 8
4.3. Operational State
[Ed note: TODO (later revision)]
4.4. Notifications
mLDP notification module consists of notification related to changes
in the operational state of an mLDP FEC. Following is a simplified
graphical representation of the data model for mLDP notifications:
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notifications:
+---n mpls-mldp-fec-event
+--ro event-type? oper-status-event-type
+--ro routing-instance-ref? rt:routing-instance-ref
+--ro ldp-protocol-name? leafref
+--ro tree-type? multipoint-type
+--ro root? inet:ip-address
+--ro (lsp-key-type)?
+--:(lsp-id-based)
| +--ro lsp-id? uint16
+--:(source-group-based)
+--ro source-addr? inet:ip-address
+--ro group-addr? inet:ip-address
Figure 9
4.5. Actions
Currently, no RPCs/actions are defined for mLDP.
5. YANG Specification
Following are actual YANG definition for LDP and mLDP constructs
defined earlier in the document.
<CODE BEGINS> file "ietf-mpls-ldp@2015-07-02.yang" -->
module ietf-mpls-ldp {
namespace "urn:ietf:params:xml:ns:yang:ietf-mpls-ldp";
// replace with IANA namespace when assigned
prefix ldp;
import ietf-inet-types {
prefix "inet";
}
import ietf-yang-types {
prefix "yang";
}
import ietf-interfaces {
prefix "if";
}
import ietf-ip {
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prefix "ip";
}
import ietf-routing {
prefix "rt";
}
import routing-policy {
prefix "rpl";
}
organization "TBD";
contact "TBD";
description
"";
revision 2015-07-02 {
description
"Initial revision.";
reference
"";
}
/*
* Features
*/
feature admin-down-config {
description
"This feature indicates that the system allows to configure
administrative down on a VRF instance and a neighbor.";
}
feature capability-end-of-lib {
description
"This feature indicates that the system allows to configure
LDP end-of-lib capability.";
}
feature capability-mldp-hsmp {
description
"This feature indicates that the system allows to configure
mLDP hub-and-spoke-multipoint capability.";
}
feature capability-mldp-node-protection {
description
"This feature indicates that the system allows to configure
mLDP node-protection capability.";
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}
feature capability-typed-wildcard-fec {
description
"This feature indicates that the system allows to configure
LDP typed-wildcard-fec capability.";
}
feature capability-upstream-label-assignment {
description
"This feature indicates that the system allows to configure
LDP upstream label assignment capability.";
}
feature forwarding-nexthop-config {
description
"This feature indicates that the system allows to configure
forwarding nexthop on interfaces.";
}
feature global-session-authentication {
description
"This feature indicates that the system allows to configure
authentication at global level.";
}
feature graceful-restart-helper-mode {
description
"This feature indicates that the system supports graceful
restart helper mode.";
}
feature mldp {
description
"This feature indicates that the system supports Multicast
LDP (mLDP).";
}
feature mldp-mofrr {
description
"This feature indicates that the system supports mLDP
Multicast only FRR (MoFRR).";
}
feature per-interface-timer-config {
description
"This feature indicates that the system allows to configure
interface hello timers at the per-interface level.";
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}
feature per-neighbor-graceful-restart-config {
description
"This feature indicates that the system allows to configure
graceful restart at the per-neighbor level.";
}
feature per-neighbor-session-attributes-config {
description
"This feature indicates that the system allows to configure
session attributes at the per-neighbor level.";
}
feature policy-extended-discovery-config {
description
"This feature indicates that the system allows to configure
policies to control the acceptance of extended neighbor
discovery hello messages.";
}
feature policy-label-assignment-config {
description
"This feature indicates that the system allows to configure
policies to assign labels according to certain prefixes.";
}
feature policy-ordered-label-config {
description
"This feature indicates that the system allows to configure
ordered label policies.";
}
feature session-downstream-on-demand-config {
description
"This feature indicates that the system allows to configure
session downstream-on-demand";
}
feature session-protection {
description
"This feature indicates that the system supports session
protection";
}
/*
* Typedefs
*/
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typedef address-family-type {
type enumeration {
enum ipv4 {
description "IPv4";
}
enum ipv6 {
description "IPv6";
}
}
description
"Address family type.";
}
typedef multipoint-type {
type enumeration {
enum p2mp {
description "Point to multipoint.";
}
enum mp2mp {
description "Multipoint to multipoint.";
}
}
description
"p2mp or mp2mp.";
}
typedef peer-list-ref {
type leafref {
path "/rpl:routing-policy/rpl:defined-sets/rpl:neighbor-set/"
+"rpl:neighbor-set-name";
}
description
"A type for a reference to a prefix list.";
}
typedef prefix-list-ref {
type leafref {
path "/rpl:routing-policy/rpl:defined-sets/rpl:prefix-set/"
+"rpl:prefix-set-name";
}
description
"A type for a reference to a prefix list.";
}
typedef oper-status-event-type {
type enumeration {
enum up {
value 1;
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description
"Operational status changed to up.";
}
enum down {
value 2;
description
"Operational status changed to down.";
}
}
description "Operational status event type for notifications.";
}
/*
* Identities
*/
identity mpls-ldp {
base "rt:routing-protocol";
description "LDP";
}
/*
* Groupings
*/
grouping ldp-instance-ref {
description
"An absolute reference to an LDP instance.";
leaf routing-instance-ref {
type rt:routing-instance-ref;
description
"Reference to the routing instance.";
}
leaf ldp-protocol-name {
type leafref {
path "/rt:routing/rt:routing-instance"
+ "[rt:name = current()/../routing-instance-ref]/"
+ "rt:routing-protocols/rt:routing-protocol/rt:name";
}
description
"Reference to an LDP protocal name.";
}
} // ldp-instance-ref
grouping ldp-neighbor-ref {
description
"An absolute reference to an LDP neighbor.";
uses ldp-instance-ref;
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leaf neighbor-ref {
type leafref {
path "/rt:routing/rt:routing-instance"
+ "[rt:name = current()/../routing-instance-ref]/"
+ "rt:routing-protocols/rt:routing-protocol"
+ "[rt:name = current()/../ldp-protocol-name]/mpls-ldp/"
+ "neighbors/neighbor/lsr-id";
}
description
"Reference to an LDP neighbor.";
}
} // ldp-neighbor-ref
grouping ldp-adjacency-ref {
description
"An absolute reference to an LDP adjacency.";
uses ldp-instance-ref;
choice adjacency-type {
description
"Interface or targeted adjacency.";
case targeted {
container targeted {
description "Targeted adjacency.";
leaf target-address {
type inet:ip-address;
description
"The target address.";
}
} // targeted
}
case link {
container link {
description "Link adjacency.";
leaf next-hop-interface {
type if:interface-ref;
description
"Interface connecting to next-hop.";
}
leaf next-hop-address {
type inet:ip-address;
must "../next-hop-interface" {
description
"Applicable when interface is specified.";
}
description
"IP address of next-hop.";
}
} // link
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}
}
} // ldp-adjacency-ref
grouping ldp-fec-event {
description
"A LDP FEC event.";
uses ldp-instance-ref;
leaf prefix {
type inet:ip-prefix;
description
"FEC.";
}
} // ldp-fec-event
grouping mldp-fec-event {
description
"A mLDP FEC event.";
uses ldp-instance-ref;
leaf tree-type {
type multipoint-type;
description
"p2mp or mp2mp.";
}
leaf root {
type inet:ip-address;
description
"Root address.";
}
choice lsp-key-type {
description
"LSP ID based or source-group based .";
case lsp-id-based {
leaf lsp-id {
type uint16;
description
"ID to identify the LSP.";
}
}
case source-group-based {
leaf source-addr {
type inet:ip-address;
description
"LSP source address.";
}
leaf group-addr {
type inet:ip-address;
description
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"Multicast group address.";
}
} // case source-group-based
}
} // mldp-fec-event
grouping basic-discovery-timers {
description
"Basic discovery timer attributes.";
leaf hello-holdtime {
type uint16 {
range 15..3600;
}
units seconds;
default 15;
description
"The time interval for which a LDP link Hello adjacency
is maintained in the absence of link Hello messages from
the LDP neighbor";
}
leaf hello-interval {
type uint16 {
range 5..1200;
}
units seconds;
default 5;
description
"The interval between consecutive LDP link Hello messages
used in basic LDP discovery";
}
} // basic-discovery-timers
grouping extended-discovery-timers {
description
"Extended discovery timer attributes.";
leaf hello-holdtime {
type uint16 {
range 15..3600;
}
units seconds;
default 45;
description
"The time interval for which LDP targeted Hello adjacency
is maintained in the absence of targeted Hello messages
from an LDP neighbor.";
}
leaf hello-interval {
type uint16 {
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range 5..3600;
}
units seconds;
default 15;
description
"The interval between consecutive LDP targeted Hello
messages used in extended LDP discovery.";
}
} // extended-discovery-timers
grouping graceful-restart-attributes {
description
"Graceful restart configuration attributes.";
container graceful-restart {
description
"Attributes for graceful restart.";
leaf enable {
type boolean;
description
"Enable or disable graceful restart.";
}
leaf helper-enable {
if-feature graceful-restart-helper-mode;
type boolean;
description
"Enable or disable graceful restart helper mode.";
}
leaf reconnect-time {
type uint16 {
range 10..1800;
}
units seconds;
description
"Specifies the time interval that the remote LDP peer
must wait for the local LDP peer to reconnect after the
remote peer detects the LDP communication failure.";
}
leaf recovery-time {
type uint16 {
range 30..3600;
}
units seconds;
description
"";
}
leaf forwarding-holdtime {
type uint16 {
range 30..3600;
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}
units seconds;
description
"";
}
} // graceful-restart
} // graceful-restart-attributes
grouping graceful-restart-attributes-per-neighbor {
description
"Per neighbor graceful restart configuration attributes.";
container graceful-restart {
description
"Attributes for graceful restart.";
leaf enable {
type boolean;
description
"Enable or disable graceful restart.";
}
leaf reconnect-time {
type uint16 {
range 10..1800;
}
units seconds;
description
"Specifies the time interval that the remote LDP peer
must wait for the local LDP peer to reconnect after the
remote peer detects the LDP communication failure.";
}
leaf recovery-time {
type uint16 {
range 30..3600;
}
units seconds;
description
"";
}
} // graceful-restart
} // graceful-restart-attributes-per-neighbor
grouping neighbor-attributes {
description "Neighbor configuration attributes.";
leaf session-ka-holdtime {
type uint16 {
range 45..3600;
}
units seconds;
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description
"The time interval after which an inactive LDP session
terminates and the corresponding TCP session closes.
Inactivity is defined as not receiving LDP packets from the
neighbor.";
}
leaf session-ka-interval {
type uint16 {
range 15..1200;
}
units seconds;
description
"The interval between successive transmissions of keepalive
packets. Keepalive packets are only sent in the absence of
other LDP packets transmitted over the LDP session.";
}
} // neighbor-attributes
grouping session-protection-per-vrf {
description "Session protection attributes.";
container session-protection {
if-feature session-protection;
description
"Session protection attributes.";
leaf enable {
type boolean;
description
"'true' if session protection is enabled.";
}
leaf duration {
type union {
type uint32;
type enumeration {
enum "infinite" {
description "The duration is infinite.";
}
}
}
units seconds;
description
"Session protection duration.";
}
leaf peer-list {
type peer-list-ref;
description
"The name of a peer ACL.";
}
} // session-protection
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} // session-protection-per-vrf
grouping session-protection-per-neighbor {
description "Session protection attributes.";
container session-protection {
if-feature session-protection;
description
"Session protection attributes.";
leaf enable {
type boolean;
description
"'true' if session protection is enabled.";
}
leaf duration {
type union {
type uint32;
type enumeration {
enum "infinite" {
description "The duration is infinite.";
}
}
}
units seconds;
description
"Session protection duration.";
}
} // session-protection
} // session-protection-per-neighbor
grouping neighbor-authentication {
description
"Neighbor authentication attributes.";
leaf md5-password {
type string {
length "1..80";
}
description
"Assigns an encrypted MD5 password to an LDP
neighbor";
} // md5-password
} // neighbor-authentication
grouping neighbor-attributes-container {
description "Container of neighbor configuration attributes.";
container neighbors {
description
"Container of neighbor configuration attributes.";
uses neighbor-authentication {
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if-feature global-session-authentication;
}
uses neighbor-attributes;
}
} // neighbor-attributes-container
grouping instance-attributes {
description "Configuration attributes at instance level.";
uses graceful-restart-attributes;
leaf igp-synchronization-delay {
type uint16 {
range 3..60;
}
units seconds;
description
"Sets the interval that the LDP waits before notifying the
Interior Gateway Protocol (IGP) that label exchange is
completed so that IGP can start advertising the normal
metric for the link.";
}
} // instance-attributes
grouping global-attributes {
description "Configuration attributes at global level.";
uses instance-attributes;
leaf nonstop-routing {
type boolean;
default false;
description
"Enables Nonstop Routing (NSR)";
}
} // global-attributes
grouping policy-attributes {
description
"LDP policy attributes.";
container label-policy {
description
"Label policy attributes.";
container independent-mode {
description
"Independent label policy attributes.";
container assign {
if-feature policy-label-assignment-config;
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description
"Label assignment policies";
choice prefix-option {
description
"Use either prefix-list or host-routes-only.";
case prefix-list {
leaf prefix-list {
type prefix-list-ref;
description
"Assign labels according to certain prefixes.";
}
}
case host-routes-only {
leaf host-routes-only {
type boolean;
description
"'true' to apply host routes only.";
}
}
} // prefix-option
}
container advertise {
description
"Label advertising policies.";
container explicit-null {
presence "Present to enable explicit null.";
description
"Enables an egress router to advertise an
explicit null label (value 0) in place of an
implicit null label (value 3) to the
penultimate hop router.";
leaf prefix-list {
type prefix-list-ref;
description
"Prefix list name. Applies the filters in the
specified prefix list to label
advertisements.
If the prefix list is not specified, explicit
null label advertisement is enabled for all
directly connected prefixes.";
}
}
leaf prefix-list {
type prefix-list-ref;
description
"Applies the prefix list to outgoing label
advertisements.";
}
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}
container accept {
description
"Label advertisement acceptance policies.";
leaf prefix-list {
type prefix-list-ref;
description
"Applies the prefix list to incoming label
advertisements.";
}
}
} // independent-mode
container ordered-mode {
if-feature policy-ordered-label-config;
description
"Ordered label policy attributes.";
container egress-lsr {
description
"Egress LSR label assignment policies";
leaf prefix-list {
type prefix-list-ref;
description
"Assign labels according to certain prefixes.";
}
}
container advertise {
description
"Label advertising policies.";
leaf prefix-list {
type prefix-list-ref;
description
"Applies the prefix list to outgoing label
advertisements.";
}
}
container accept {
description
"Label advertisement acceptance policies.";
leaf prefix-list {
type prefix-list-ref;
description
"Applies the prefix list to incoming label
advertisements.";
}
}
} // ordered-mode
} // label-policy
} // policy-attributes
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grouping neighbor-af-policy-attributes {
description
"LDP policy attributes under neighbor address-family.";
container label-policy {
description
"Label policy attributes.";
container advertise {
description
"Label advertising policies.";
leaf prefix-list {
type prefix-list-ref;
description
"Applies the prefix list to outgoing label
advertisements.";
}
}
container accept {
description
"Label advertisement acceptance policies.";
leaf prefix-list {
type prefix-list-ref;
description
"Applies the prefix list to incoming label
advertisements.";
}
} // accept
} // label-policy
} // neighbor-af-policy-attributes
grouping extended-discovery-policy-attributes {
description
"LDP policy to control the acceptance of extended neighbor
discovery hello messages.";
container hello-accept {
if-feature policy-extended-discovery-config;
description
"Extended discovery acceptance policies.";
leaf enable {
type boolean;
description
"'true' to accept; 'false' to deny.";
}
leaf peer-list {
type peer-list-ref;
description
"The name of a peer ACL.";
}
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} // hello-accept
} // extended-discovery-policy-attributes
grouping mldp-capabilities {
description
"mLDP capabilities.";
container p2mp {
description
"Configure point-to-multipoint capability.";
leaf enable {
type boolean;
description
"Enable point-to-multipoint.";
}
}
container mp2mp {
description
"Configure multipoint-to-multipoint capability.";
leaf enable {
type boolean;
description
"Enable multipoint-to-multipoint.";
}
}
container make-before-break {
description
"Configure make-before-break capability.";
leaf enable {
type boolean;
description
"Enable make-before-break.";
}
leaf switchover-delay {
type uint16;
units seconds;
description
"Switchover delay in seconds.";
}
leaf timeout {
type uint16;
units seconds;
description
"Timeout in seconds.";
}
}
container hub-and-spoke {
if-feature capability-mldp-hsmp;
description
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"Configure hub-and-spoke-multipoint capability.";
reference
"RFC7140: LDP Extensions for Hub and Spoke Multipoint
Label Switched Path";
leaf enable {
type boolean;
description
"Enable hub-and-spoke-multipoint.";
}
}
container node-protection {
if-feature capability-mldp-node-protection;
description
"Configure node-protection capability.";
reference
"draft-ietf-mpls-mldp-node-protection: mLDP Node
Protection.";
leaf plr {
type boolean;
description
"Point of Local Repair capable for MP LSP node
protection.";
}
container merge-point {
description
"Merge Point capable for MP LSP node protection.";
leaf enable {
type boolean;
description
"Enable merge point capability.";
}
leaf targeted-session-teardown-delay {
type uint16;
units seconds;
description
"Targeted session teardown delay.";
}
} // merge-point
}
} // mldp-capabilities
grouping mldp-configured-lsp-roots {
description
"mLDP roots containers.";
container roots-ipv4 {
when "../../../af = 'ipv4'" {
description
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"Only for IPv4.";
}
description
"Configured IPv4 multicast LSPs.";
list root {
key "root-addr";
description
"List of roots for configured multicast LSPs.";
leaf root-addr {
type inet:ipv4-address;
description
"Root address.";
}
list lsp {
must "(lsp-id = 0 and source-addr != '0.0.0.0' and "
+ "group-addr != '0.0.0.0') or "
+ "(lsp-id != 0 and source-addr = '0.0.0.0' and "
+ "group-addr = '0.0.0.0')" {
description
"A LSP can be identified by either lsp-id or
(source-addr, group-addr).";
}
key "lsp-id source-addr group-addr";
description
"List of LSPs.";
leaf lsp-id {
type uint16;
description "ID to identify the LSP.";
}
leaf source-addr {
type inet:ipv4-address-no-zone;
description
"Source address.";
}
leaf group-addr {
type inet:ipv4-address-no-zone;
description
"Group address.";
}
} // list lsp
} // list root
} // roots-ipv4
container roots-ipv6 {
when "../../../af = 'ipv6'" {
description
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"Only for IPv6.";
}
description
"Configured IPv6 multicast LSPs.";
list root {
key "root-addr";
description
"List of roots for configured multicast LSPs.";
leaf root-addr {
type inet:ipv6-address;
description
"Root address.";
}
list lsp {
must "(lsp-id = 0 and source-addr != '::' and "
+ "group-addr != '::') or "
+ "(lsp-id != 0 and source-addr = '::' and "
+ "group-addr = '::')" {
description
"A LSP can be identified by either lsp-id or
(source-addr, group-addr).";
}
key "lsp-id source-addr group-addr";
description
"List of LSPs.";
leaf lsp-id {
type uint16;
description "ID to identify the LSP.";
}
leaf source-addr {
type inet:ipv6-address-no-zone;
description
"Source address.";
}
leaf group-addr {
type inet:ipv6-address-no-zone;
description
"Group address.";
}
} // list lsp
} // list root
} // roots-ipv6
} // mldp-configured-lsp-roots
/*
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* Configuration data nodes
*/
augment "/rt:routing/rt:routing-instance/rt:routing-protocols/"
+ "rt:routing-protocol" {
when "rt:type = 'ldp:mpls-ldp'" {
description
"This augment is only valid for a protocol instance
of LDP.";
}
description "LDP augmentation.";
container mpls-ldp {
description
"LDP.";
leaf lsr-id {
type yang:dotted-quad;
description "Router ID.";
}
container mldp {
if-feature mldp;
description
"mLDP attributes at per instance level. Defining attributes
here does not enable any MP capabilities. MP capabilities
need to be explicitly enabled under container capability.";
leaf enable {
type boolean;
description
"Enable mLDP.";
}
list address-family {
key "af";
description
"Per-af params.";
leaf af {
type address-family-type;
description
"Address family type value.";
}
container multicast-only-frr {
if-feature mldp-mofrr;
description
"Multicast only FRR (MoFRR) policy.";
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leaf prefix-list {
type prefix-list-ref;
description
"Enables MoFRR for the specified access list.";
}
} // multicast-only-frr
container recursive-fec {
description
"Recursive FEC policy.";
leaf prefix-list {
type prefix-list-ref;
description
"Enables recursive FEC for the specified access
list.";
}
} // recursive-for
container configured-lsps {
description
"Configured multicast LSPs.";
container p2mp {
description
"Configured point-to-multipoint LSPs.";
uses mldp-configured-lsp-roots;
}
container mp2mp {
description
"Configured multipoint-to-multipoint LSPs.";
uses mldp-configured-lsp-roots;
}
} // configured-lsps
} // list address-family
} // mldp
container capability {
description "Configure capability.";
container end-of-lib {
if-feature capability-end-of-lib;
description
"Configure upstream label assignment capability.";
leaf enable {
type boolean;
description
"Enable end-of-lib capability.";
}
}
container typed-wildcard-fec {
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if-feature capability-typed-wildcard-fec;
description
"Configure typed-wildcard-fec capability.";
leaf enable {
type boolean;
description
"Enable typed-wildcard-fec capability.";
}
}
container upstream-label-assignment {
if-feature capability-upstream-label-assignment;
description
"Configure upstream label assignment capability.";
leaf enable {
type boolean;
description
"Enable upstream label assignment.";
}
}
container mldp {
if-feature mldp;
description
"Multipoint capabilities.";
uses mldp-capabilities;
}
} // capability
uses global-attributes;
list address-family {
key "af";
description
"Per-vrf per-af params.";
leaf af {
type address-family-type;
description
"Address family type value.";
}
leaf enable {
type boolean;
description
"'true' to enable the address family.";
}
uses policy-attributes;
container ipv4 {
when "../af = 'ipv4'" {
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description
"Only for IPv4.";
}
description
"IPv4 address family.";
leaf transport-address {
type inet:ipv4-address;
description
"The transport address advertised in LDP Hello
messages.";
}
} // ipv4
container ipv6 {
when "../af = 'ipv6'" {
description
"Only for IPv6.";
}
description
"IPv6 address family.";
leaf transport-address {
type inet:ipv6-address;
description
"The transport address advertised in LDP Hello
messages.";
}
} // ipv6
}
container discovery {
description
"Neibgbor discovery configuration.";
container interfaces {
description
"A list of interfaces for basic descovery.";
uses basic-discovery-timers;
list interface {
key "interface";
description
"List of LDP interfaces.";
leaf interface {
type if:interface-ref;
description
"Interface.";
}
uses basic-discovery-timers {
if-feature per-interface-timer-config;
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}
leaf igp-synchronization-delay {
if-feature per-interface-timer-config;
type uint16 {
range 3..60;
}
units seconds;
description
"Sets the interval that the LDP waits before
notifying the Interior Gateway Protocol (IGP) that
label exchange is completed so that IGP can start
advertising the normal metric for the link.";
}
list address-family {
key "af";
description
"Per-vrf per-af params.";
leaf af {
type address-family-type;
description
"Address family type value.";
}
leaf enable {
type boolean;
description
"Enable the address family on the interface.";
}
container ipv4 {
must "/if:interfaces/if:interface"
+ "[name = current()/../../interface]/ip:ipv4" {
description
"Only if IPv4 is enabled on the interface.";
}
description
"IPv4 address family.";
leaf transport-address {
type union {
type enumeration {
enum "use-interface-address" {
description
"Use interface address as the transport
address.";
}
}
type inet:ipv4-address;
}
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description
"IP address to be advertised as the LDP
transport address.";
}
}
container ipv6 {
must "/if:interfaces/if:interface"
+ "[name = current()/../../interface]/ip:ipv6" {
description
"Only if IPv6 is enabled on the interface.";
}
description
"IPv6 address family.";
leaf transport-address {
type union {
type enumeration {
enum "use-interface-address" {
description
"Use interface address as the transport
address.";
}
}
type inet:ipv4-address;
}
description
"IP address to be advertised as the LDP
transport address.";
}
} // ipv6
} // address-family
} // list interface
} // interfaces
container targeted
{
description
"A list of targeted neighbors for extended discovery.";
uses extended-discovery-timers;
uses extended-discovery-policy-attributes;
container address-family {
description
"Per-vrf per-af params.";
container ipv4 {
description
"IPv4 address family.";
list target {
key "address";
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description
"Targeted discovery params.";
leaf address {
type inet:ipv4-address;
description
"Configures a remote LDP neighbor and enables
extended LDP discovery of the specified
neighbor.";
}
leaf enable {
type boolean;
description
"Enable the target.";
}
}
} // ipv4
container ipv6 {
description
"IPv6 address family.";
list target {
key "address";
description
"Targeted discovery params.";
leaf address {
type inet:ipv6-address;
description
"Configures a remote LDP neighbor and enables
extended LDP discovery of the specified
neighbor.";
}
leaf enable {
type boolean;
description
"Enable the target.";
}
}
} // ipv6
} // address-family
} // targeted
} // discovery
container forwarding-nexthop {
if-feature forwarding-nexthop-config;
description
"Configuration for forwarding nexthop.";
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container interfaces {
description
"A list of interfaces on which forwarding is disabled.";
list interface {
key "interface";
description
"List of LDP interfaces.";
leaf interface {
type if:interface-ref;
description
"Interface.";
}
list address-family {
key "af";
description
"Per-vrf per-af params.";
leaf af {
type address-family-type;
description
"Address family type value.";
}
leaf ldp-disable {
type boolean;
description
"Disable LDP forwarding on the interface.";
}
leaf mldp-disable {
if-feature mldp;
type boolean;
description
"Disable mLDP forwarding on the interface.";
}
} // address-family
} // list interface
} // interfaces
} // forwarding-nexthop
container neighbors {
description
"Neighbors configuration attributes.";
uses neighbor-authentication {
if-feature global-session-authentication;
}
uses neighbor-attributes;
container session-downstream-on-demand {
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if-feature session-downstream-on-demand-config;
description
"Session downstream-on-demand attributes.";
leaf enable {
type boolean;
description
"'true' if session downstream-on-demand is enabled.";
}
leaf peer-list {
type peer-list-ref;
description
"The name of a peer ACL.";
}
}
uses session-protection-per-vrf;
list neighbor {
key "lsr-id";
description
"List of neighbors.";
leaf lsr-id {
type union {
type yang:dotted-quad;
type uint32;
}
description "LSR ID.";
}
leaf admin-down {
type boolean;
default false;
description
"'true' to disable the neighbor.";
}
container capability {
description
"Per neighbor capability";
container mldp {
if-feature mldp;
description
"mLDP capabilities.";
uses mldp-capabilities;
}
}
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uses neighbor-authentication;
uses graceful-restart-attributes-per-neighbor {
if-feature per-neighbor-graceful-restart-config;
}
uses neighbor-attributes {
if-feature per-neighbor-session-attributes-config;
}
uses session-protection-per-neighbor;
container address-family {
description
"Per-vrf per-af params.";
container ipv4 {
description
"IPv4 address family.";
uses neighbor-af-policy-attributes;
}
container ipv6 {
description
"IPv6 address family.";
uses neighbor-af-policy-attributes;
} // ipv6
} // address-family
} // list neighbor
} // neighbors
} // container mpls-ldp
}
/*
* Operational state data nodes
*/
augment "/rt:routing-state/rt:routing-instance/"
+ "rt:routing-protocols/rt:routing-protocol" {
when "rt:type = 'ldp:mpls-ldp'" {
description
"This augment is only valid for a protocol instance
of type 'ldp'.";
}
description
"LDP state.";
container mpls-ldp {
description "LDP";
}
}
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/*
* RPCs
*/
rpc mpls-ldp-clear-neighbor {
description
"Clears the session to the neighbor.";
input {
uses ldp-instance-ref {
description
"VRF instance name. If this is not provided
then all instances are cleared.";
}
leaf lsr-id {
type union {
type yang:dotted-quad;
type uint32;
}
description
"LSR ID of neighbor to be cleared. If this is not provided
then all neighbors are cleared";
}
}
}
rpc mpls-ldp-clear-adjacency {
description
"Clears the hello adjacency";
input {
uses ldp-instance-ref {
description
"VRF instance name. If this is not provided
then all instances are cleared.";
}
container adjacency {
description
"Link adjacency or targettted adjacency. If this is not
provided then all hello adjacencies are cleared";
choice adjacency-type {
description "Adjacency type.";
case targeted {
container targeted {
presence "Present to clear targeted adjacencies.";
description
"Clear targeted adjacencies.";
leaf target-address {
type inet:ip-address;
description
"The target address. If this is not provided then
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all targeted adjacencies are cleared";
}
} // targeted
}
case link {
container link {
presence "Present to clear link adjacencies.";
description
"Clear link adjacencies.";
leaf next-hop-interface {
type if:interface-ref;
description
"Interface connecting to next-hop. If this is not
provided then all link adjacencies are cleared.";
}
leaf next-hop-address {
type inet:ip-address;
must "../next-hop-interface" {
description
"Applicable when interface is specified.";
}
description
"IP address of next-hop. If this is not provided
then adjacencies to all next-hops on the given
interface are cleared.";
} // next-hop-address
} // link
}
}
}
}
}
rpc mpls-ldp-clear-neighbor-statistics {
description
"Clears protocol statistics (e.g. sent and received
counters).";
input {
uses ldp-instance-ref {
description
"VRF instance name. If this is not provided
then all instances are cleared.";
}
leaf lsr-id {
type union {
type yang:dotted-quad;
type uint32;
}
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description
"LSR ID of neighbor whose statistic are to be cleared.
If this is not provided then all neighbors statistics are
cleared";
}
}
}
/*
* Notifications
*/
notification mpls-ldp-neighbor-event {
description
"Notification event for a change of LDP neighbor operational
status.";
leaf event-type {
type oper-status-event-type;
description "Event type.";
}
uses ldp-neighbor-ref;
}
notification mpls-ldp-adjacency-event {
description
"Notification event for a change of LDP adjacency operational
status.";
leaf event-type {
type oper-status-event-type;
description "Event type.";
}
uses ldp-adjacency-ref;
}
notification mpls-ldp-fec-event {
description
"Notification event for a change of FEC status.";
leaf event-type {
type oper-status-event-type;
description "Event type.";
}
uses ldp-fec-event;
}
notification mpls-mldp-fec-event {
description
"Notification event for a change of FEC status.";
leaf event-type {
type oper-status-event-type;
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description "Event type.";
}
uses mldp-fec-event;
}
}
<CODE ENDS>
Figure 10
6. Security Considerations
The configuration, state, action and notification data defined in
this document are designed to be accessed via the NETCONF protocol
[RFC6241]. The lowest NETCONF layer is the secure transport layer
and the mandatory-to-implement secure transport is SSH [RFC6242].
The NETCONF access control model [RFC6536] provides means to restrict
access for particular NETCONF users to a pre-configured subset of all
available NETCONF protocol operations and content.
LDP is a MPLS protocol that is used to establish MPLS transport LSPs.
So it is critical to ensure security of the protocol to avoid
disruption of the services that depend on these transport LSPs.
There are a number of data nodes defined in the LDP and mLDP 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.
The security concerns listed above are, however, no different than
faced by other routing protocols. Hence, this draft does not change
any underlying security issues inherent in [I-D.ietf-netmod-routing-
cfg]
7. IANA Considerations
None.
8. Acknowledgments
The authors would like to acknowledge Eddie Chami, Mannan Venkatesan,
and Sowmya Krishnaswamy for their contribution to this document. We
also acknowledge Ladislav Lhotka and Danial Johari for their useful
comments.
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9. References
9.1. Normative References
[I-D.ietf-mpls-mldp-node-protection]
Wijnands, I., Raza, K., Rosen, E., Atlas, A., Tantsura,
J., and Q. Zhao, "mLDP Node Protection", draft-ietf-mpls-
mldp-node-protection-05 (work in progress), February 2015.
[I-D.ietf-netmod-routing-cfg]
Lhotka, L. and A. Lindem, "A YANG Data Model for Routing
Management", draft-ietf-netmod-routing-cfg-19 (work in
progress), May 2015.
[I-D.shaikh-rtgwg-policy-model]
Shaikh, A., Shakir, R., D'Souza, K., and C. Chase,
"Routing Policy Configuration Model for Service Provider
Networks", draft-shaikh-rtgwg-policy-model-01 (work in
progress), July 2015.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC5036] Andersson, L., Minei, I., and B. Thomas, "LDP
Specification", RFC 5036, October 2007.
[RFC5561] Thomas, B., Raza, K., Aggarwal, S., Aggarwal, R., and JL.
Le Roux, "LDP Capabilities", RFC 5561, July 2009.
[RFC5918] Asati, R., Minei, I., and B. Thomas, "Label Distribution
Protocol (LDP) 'Typed Wildcard' Forward Equivalence Class
(FEC)", RFC 5918, August 2010.
[RFC5919] Asati, R., Mohapatra, P., Chen, E., and B. Thomas,
"Signaling LDP Label Advertisement Completion", RFC 5919,
August 2010.
[RFC6388] Wijnands, IJ., Minei, I., Kompella, K., and B. Thomas,
"Label Distribution Protocol Extensions for Point-to-
Multipoint and Multipoint-to-Multipoint Label Switched
Paths", RFC 6388, November 2011.
[RFC6389] Aggarwal, R. and JL. Le Roux, "MPLS Upstream Label
Assignment for LDP", RFC 6389, November 2011.
[RFC6512] Wijnands, IJ., Rosen, E., Napierala, M., and N. Leymann,
"Using Multipoint LDP When the Backbone Has No Route to
the Root", RFC 6512, February 2012.
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[RFC6826] Wijnands, IJ., Eckert, T., Leymann, N., and M. Napierala,
"Multipoint LDP In-Band Signaling for Point-to-Multipoint
and Multipoint-to-Multipoint Label Switched Paths", RFC
6826, January 2013.
[RFC7060] Napierala, M., Rosen, E., and IJ. Wijnands, "Using LDP
Multipoint Extensions on Targeted LDP Sessions", RFC 7060,
November 2013.
[RFC7140] Jin, L., Jounay, F., Wijnands, IJ., and N. Leymann, "LDP
Extensions for Hub and Spoke Multipoint Label Switched
Path", RFC 7140, March 2014.
[RFC7438] Wijnands, IJ., Rosen, E., Gulko, A., Joorde, U., and J.
Tantsura, "Multipoint LDP (mLDP) In-Band Signaling with
Wildcards", RFC 7438, January 2015.
[RFC7552] Asati, R., Pignataro, C., Raza, K., Manral, V., and R.
Papneja, "Updates to LDP for IPv6", RFC 7552, June 2015.
9.2. Informative References
[I-D.iwijnand-mpls-mldp-multi-topology]
Wijnands, I. and K. Raza, "mLDP Extensions for Multi
Topology Routing", draft-iwijnand-mpls-mldp-multi-
topology-03 (work in progress), June 2013.
[RFC6020] Bjorklund, M., "YANG - A Data Modeling Language for the
Network Configuration Protocol (NETCONF)", RFC 6020,
October 2010.
[RFC6241] Enns, R., Bjorklund, M., Schoenwaelder, J., and A.
Bierman, "Network Configuration Protocol (NETCONF)", RFC
6241, June 2011.
[RFC6242] Wasserman, M., "Using the NETCONF Protocol over Secure
Shell (SSH)", RFC 6242, June 2011.
[RFC6536] Bierman, A. and M. Bjorklund, "Network Configuration
Protocol (NETCONF) Access Control Model", RFC 6536, March
2012.
[RFC7307] Zhao, Q., Raza, K., Zhou, C., Fang, L., Li, L., and D.
King, "LDP Extensions for Multi-Topology", RFC 7307, July
2014.
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Authors' Addresses
Kamran Raza
Cisco Systems, Inc.
Email: skraza@cisco.com
Xufeng Liu
Ericsson
Email: xufeng.liu@ericsson.com
Santosh Esale
Juniper Networks
Email: sesale@juniper.net
Xia Chen
Huawei Technologies
Email: jescia.chenxia@huawei.com
Himanshu Shah
Ciena Corporation
Email: hshah@ciena.com
Reshad Rahman
Cisco Systems, Inc.
Email: rrahman@cisco.com
Rajiv Asati
Cisco Systems, Inc.
Email: rajiva@cisco.com
Nagendra Kumar
Cisco Systems, Inc.
Email: naikumar@cisco.com
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Jeff Tantsura
Ericsson
Email: jeff.tantsura@ericsson.com
Loa Andersson
Huawei Technologies
Email: loa@pi.nu
Matthew Bocci
Alcatel-Lucent
Email: matthew.bocci@alcatel-lucent.com
Vishnu P. Beeram
Juniper Networks
Email: vbeeram@juniper.net
Stephane Litkowski
Orange
Email: stephane.litkowski@orange.com
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