YANG Data Model for SR and SR TE Topologies on MPLS Data Plane
draft-ietf-teas-yang-sr-te-topo-13
| Document | Type | Active Internet-Draft (teas WG) | |
|---|---|---|---|
| Authors | Xufeng Liu , Igor Bryskin , Vishnu Pavan Beeram , Tarek Saad , Himanshu C. Shah , Stephane Litkowski | ||
| Last updated | 2022-03-01 | ||
| Replaces | draft-liu-teas-yang-sr-te-topo | ||
| Stream | Internet Engineering Task Force (IETF) | ||
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draft-ietf-teas-yang-sr-te-topo-13
Network Working Group X. Liu
Internet-Draft IBM Corporation
Intended status: Standards Track I. Bryskin
Expires: September 2, 2022 Individual
V. Beeram
T. Saad
Juniper Networks
H. Shah
Ciena
S. Litkowski
Cisco
March 1, 2022
YANG Data Model for SR and SR TE Topologies on MPLS Data Plane
draft-ietf-teas-yang-sr-te-topo-13
Abstract
This document defines a YANG data model for Segment Routing (SR)
topology and Segment Routing (SR) traffic engineering (TE) topology,
using MPLS data plane.
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 https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on September 2, 2022.
Copyright Notice
Copyright (c) 2022 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
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publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3
1.2. Tree Diagrams . . . . . . . . . . . . . . . . . . . . . . 3
1.3. Prefixes in Data Node Names . . . . . . . . . . . . . . . 3
2. Modeling Considerations . . . . . . . . . . . . . . . . . . . 4
2.1. Segment Routing (SR) MPLS Topology . . . . . . . . . . . 4
2.2. Segment Routing (SR) MPLS TE Topology . . . . . . . . . . 4
2.3. Relations to ietf-segment-routing . . . . . . . . . . . . 7
2.4. Topology Type Modeling . . . . . . . . . . . . . . . . . 7
2.5. Topology Attributes . . . . . . . . . . . . . . . . . . . 7
2.6. Node Attributes . . . . . . . . . . . . . . . . . . . . . 7
2.7. Link Attributes . . . . . . . . . . . . . . . . . . . . . 9
3. Model Structure . . . . . . . . . . . . . . . . . . . . . . . 10
4. YANG Module . . . . . . . . . . . . . . . . . . . . . . . . . 11
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 20
6. Security Considerations . . . . . . . . . . . . . . . . . . . 21
7. References . . . . . . . . . . . . . . . . . . . . . . . . . 23
7.1. Normative References . . . . . . . . . . . . . . . . . . 23
7.2. Informative References . . . . . . . . . . . . . . . . . 25
Appendix A. Companion YANG Model for Non-NMDA Compliant
Implementations . . . . . . . . . . . . . . . . . . 26
A.1. SR MPLS Topology State Module . . . . . . . . . . . . . . 26
Appendix B. Data Tree Example . . . . . . . . . . . . . . . . . 29
B.1. SR MPLS Topology with TE Not Enabled . . . . . . . . . . 30
B.2. SR MPLS Topology with TE Enabled . . . . . . . . . . . . 37
Appendix C. Contributors . . . . . . . . . . . . . . . . . . . . 52
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 52
1. Introduction
This document defines a YANG [RFC7950] data model for describing the
presentations of Segment Routing (SR) topology and Segment Routing
(SR) traffic engineering (TE) topology. The version of the model
limits the transport type to an MPLS dataplane.
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1.1. Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
The following terms are defined in [RFC7950] and are not redefined
here:
o augment
o data model
o data node
1.2. Tree Diagrams
Tree diagrams used in this document follow the notation defined in
[RFC8340].
1.3. Prefixes in Data Node Names
In this document, names of data nodes, actions, and other data model
objects are often used without a prefix, as long as it is clear from
the context in which YANG module each name is defined. Otherwise,
names are prefixed using the standard prefix associated with the
corresponding YANG module, as shown in Table 1.
+--------+--------------------------+-------------------------------+
| Prefix | YANG module | Reference |
+--------+--------------------------+-------------------------------+
| nw | ietf-network | [RFC8345] |
| nt | ietf-network-topology | [RFC8345] |
| l3t | ietf-l3-unicast-topology | [RFC8346] |
| sr-cmn | ietf-segment-routing- | [RFC9020] |
| | common | |
| tet | ietf-te-topology | [RFC8795] |
| tet- | ietf-te-topology-packet | [I-D.ietf-teas-yang-l3-te-top |
| pkt | | o] |
+--------+--------------------------+-------------------------------+
Table 1: Prefixes and Corresponding YANG Modules
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2. Modeling Considerations
2.1. Segment Routing (SR) MPLS Topology
The Layer 3 network topology model is discussed in [RFC8346]. The
Segment Routing (SR) MPLS topology model proposed in this document
augments and uses the ietf-l3-unicast-topology module defined in
[RFC8346]. SR MPLS related attributes are covered in the ietf-sr-
mpls-topology module.
+------------------------------+
| Layer 3 Network Topology |
| ietf-l3-unicast-topology |
+---------------^--------------+
|
|
|
|
+------------^-----------+
| SR MPLS Topology |
| ietf-sr-mpls-topology |
+------------------------+
Figure 1: SR MPLS Topology Augmentation
2.2. Segment Routing (SR) MPLS TE Topology
A Segment Routing (SR) MPLS TE topology is an instance of SR MPLS
topology with TE enabled. In order to instantiate an SR MPLS TE
topology, the ietf-sr-mpls-topology module defined in this document
can be used together with the ietf-te-topology module defined in
[RFC8795] and the ietf-te-topology-packet module defined in
[I-D.ietf-teas-yang-l3-te-topo]. All these modules directly or
indirectly augment the ietf-network-topology module defind in
[RFC8345], as shown in Figure 2.
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+---------------------------+
| Network Topology |
| ietf-network-topology |
+-^-----------------------^-+
/ \
/ \
/ \
/ \
+-------------^-------------+ +-------------^-------------+
| Layer 3 Unicast Topology | | TE Topology |
| ietf-l3-unicast-topology | | ietf-te-topology |
+-------------^-------------+ +-------------^-------------+
| |
| |
| |
| |
+-------------^-------------+ +-------------^-------------+
| SR MPLS Topology | | TE Packet Topology |
| ietf-sr-mpls-topology | | ietf-te-topology-packet |
+---------------------------+ +---------------------------+
Figure 2: SR TE Topology Instance Inheritance Relations
Figure 3 shows the data structure of an SR TE topology instance.
Because of the augmentation relationships shown in Figure 2, a data
instance of an SR MPLS TE topology contains the capabilities from all
these modules, so that the data includes the attributes from ietf-
network-topology, ietf-l3-unicast-topology, ietf-sr-mpls-topology,
ietf-te-topology, and ietf-te-topology-packet.
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+--------------------------------------------------------+
| ietf-network-topology: |
| network-id (key) |
| network-types: { |
| l3-unicast-topology: { |
| sr-mpls{} |
| } |
| te-topology: { |
| packet{} |
| } |
| } |
| <other network topology attributes> |
+-----------------------------+--------------------------+
| ietf-l3-unicast-topology: | ietf-te-topology: |
| <L3 unicast attributes> | <TE attributes> |
+-----------------------------+--------------------------+
| ietf-sr-mpls-topology: | ietf-te-topology-packet: |
| <SR MPLS attributes> | <TE packet attributes> |
+-----------------------------+--------------------------+
Figure 3: SR TE topology instance data structure
Each type of topology is indicated by a YANG presence container which
augments "network-types" as defined in [RFC8345].2 For the five types
of topologies above, the data representations are:
Base network topology [RFC8345]:
/nw:networks/nw:network/nw:network-types
Layer 3 Unicast Topology [RFC8346]:
/nw:networks/nw:network/nw:network-types/l3t:l3-unicast-topology
SR MPLS Topology (defined in this document):
/nw:networks/nw:network/nw:network-types/l3t:l3-unicast-topology/
srmt:sr-mpls
TE Topology [RFC8795]:
/nw:networks/nw:network/nw:network-types/tet:te-topology
TE Packet Topology [I-D.ietf-teas-yang-l3-te-topo]:
/nw:networks/nw:network/nw:network-types/tet:te-topology/tet-
pkt:packet
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2.3. Relations to ietf-segment-routing
[RFC9020] defines ietf-segment-routing that is a model intended to be
used on network elements to configure or operate segment routing;
ietf-sr-mpls-topology defined in this document is intended to be used
on a controller for the network-wide operations such as path
computation.
SR MPLS topology model shares many modeling constructs defined in
ietf-segment-routing. The module ietf-sr-mpls-topology uses the
types and groupings defined in ietf-segment-routing.
2.4. Topology Type Modeling
A new topology type is defined in this document, to indicate a
topology that is a Segment Routing (SR) topology on an MPLS
dataplane.
augment /nw:networks/nw:network/nw:network-types
/l3t:l3-unicast-topology:
+--rw sr-mpls!
Section 4.4.8 of RFC 8345 describes how network types are represented
using nested presence container. In this document, the presence
container sr-mpls is used for such a purpose.
2.5. Topology Attributes
The Segment Routing attributes with topology-wide impacts are modeled
by augmenting the container "l3-topology-attributes" in the L3
topology model [RFC8346]. SRGB (Segment Routing Global Block) is
covered in this augmentation. A SR domain is mapped to a topology in
this model.
augment /nw:networks/nw:network/l3t:l3-topology-attributes:
+--rw sr-mpls
+--rw srgb* [lower-bound upper-bound]
+--rw lower-bound uint32
+--rw upper-bound uint32
2.6. Node Attributes
The Segment Routing attributes within the node scope are modeled by
augmenting the sub tree /nw:networks/nw:network/nw:node/ in the L3
topology model [RFC8346].
The SR attributes that have node-scope impact are modeled by
augmenting the container "l3-node-attributes" in the L3 topology
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model, including the SR capabilities, SRGB (Segment Routing Global
Block), and SRLB (Segment Routing Local Block) specified on this
mode. This model also provides the information about how these SR
attributes are learned:
The presence container sr-mpls is used to indicate that SR MPLS is
enabled on this node when the container is present.
augment /nw:networks/nw:network/nw:node/l3t:l3-node-attributes:
+--rw sr-mpls!
+--rw srgb* [lower-bound upper-bound]
| +--rw lower-bound uint32
| +--rw upper-bound uint32
+--rw srlb* [lower-bound upper-bound]
| +--rw lower-bound uint32
| +--rw upper-bound uint32
+--rw msds {msd}?
| +--rw node-msd* [msd-type]
| +--rw msd-type identityref
| +--rw msd-value? uint8
+--ro information-source? enumeration
+--ro information-source-instance? string
+--ro information-source-state
+--ro credibility-preference? uint16
The SR attributes that are related to a IGP-Prefix segment are
modeled by augmenting the list entry "prefix" in the L3 topology
model:
augment /nw:networks/nw:network/nw:node/l3t:l3-node-attributes
/l3t:prefix:
+--rw sr-mpls!
+--rw sids
+--rw sid* [algorithm]
+--rw value-type? enumeration
+--rw start-sid uint32
+--rw range? uint32
+--rw algorithm identityref
+--rw last-hop-behavior? enumeration
| {sid-last-hop-behavior}?
+--rw is-local? boolean
+--rw is-node? boolean
+--ro is-readvertisment? boolean
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2.7. Link Attributes
A link in the topology model connects the termination point on the
source node to the termination point on the destination node. When
such a link is instantiated, the bindings between the nodes and the
corresponding Adj-SIDs are formed, and the resulting FIB entries are
installed.
A link in the topology model is mapped to an SR Adjacency Segment,
formed by a pair of interfaces on two respective adjacent nodes. The
SR Adjacency Segment attributes are modeled by augmenting the link
attributes of the L3 topology model [RFC8346]. The modeling
structure is as follows:
augment /nw:networks/nw:network/nt:link/l3t:l3-link-attributes:
+--rw sr-mpls!
+--rw msds {msd}?
| +--rw link-msd* [msd-type]
| +--rw msd-type identityref
| +--rw msd-value? uint8
+--rw sids
| +--rw sid* [value-type sid]
| +--rw value-type enumeration
| +--rw sid uint32
| +--rw address-family? enumeration
| +--rw is-eligible-for-protection? boolean
| +--rw is-local? boolean
| +--rw is-part-of-set? boolean
| +--rw is-persistent? boolean
| +--rw is-on-lan? boolean
| +--rw weight? uint8
+--ro information-source? enumeration
+--ro information-source-instance? string
+--ro information-source-state
+--ro credibility-preference? uint16
IGPs [RFC8665] [RFC8666] [RFC8667] and BGP-LS [RFC7752]
[I-D.ietf-idr-bgp-ls-segment-routing-ext] can be supported by the
model, the leaf "information-source" is used to indicate where the
information is from.
The bundling capability of the Adjacency Segemnt is achieved by re-
using the existing modeling construct (i.e. "bundle-stack-level")
under /nw:networks/nw:network/nt:link/tet:te [RFC8795]
The presence container sr-mpls is used to indicate that SR SMPL is
enabled on this link when the container is present.
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3. Model Structure
The model tree structure of the Segment Routing (SR) topology module
is as shown below:
module: ietf-sr-mpls-topology
augment /nw:networks/nw:network/nw:network-types
/l3t:l3-unicast-topology:
+--rw sr-mpls!
augment /nw:networks/nw:network/l3t:l3-topology-attributes:
+--rw sr-mpls
+--rw srgb* [lower-bound upper-bound]
+--rw lower-bound uint32
+--rw upper-bound uint32
augment /nw:networks/nw:network/nw:node/l3t:l3-node-attributes:
+--rw sr-mpls!
+--rw srgb* [lower-bound upper-bound]
| +--rw lower-bound uint32
| +--rw upper-bound uint32
+--rw srlb* [lower-bound upper-bound]
| +--rw lower-bound uint32
| +--rw upper-bound uint32
+--rw msds {msd}?
| +--rw node-msd* [msd-type]
| +--rw msd-type identityref
| +--rw msd-value? uint8
+--ro information-source? enumeration
+--ro information-source-instance? string
+--ro information-source-state
+--ro credibility-preference? uint16
augment /nw:networks/nw:network/nw:node/l3t:l3-node-attributes
/l3t:prefix:
+--rw sr-mpls!
+--rw sids
+--rw sid* [algorithm]
+--rw value-type? enumeration
+--rw start-sid uint32
+--rw range? uint32
+--rw algorithm identityref
+--rw last-hop-behavior? enumeration
| {sid-last-hop-behavior}?
+--rw is-local? boolean
+--rw is-node? boolean
+--ro is-readvertisment? boolean
augment /nw:networks/nw:network/nt:link/l3t:l3-link-attributes:
+--rw sr-mpls!
+--rw msds {msd}?
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| +--rw link-msd* [msd-type]
| +--rw msd-type identityref
| +--rw msd-value? uint8
+--rw sids
| +--rw sid* [value-type sid]
| +--rw value-type enumeration
| +--rw sid uint32
| +--rw address-family? enumeration
| +--rw is-eligible-for-protection? boolean
| +--rw is-local? boolean
| +--rw is-part-of-set? boolean
| +--rw is-persistent? boolean
| +--rw is-on-lan? boolean
| +--rw weight? uint8
+--ro information-source? enumeration
+--ro information-source-instance? string
+--ro information-source-state
+--ro credibility-preference? uint16
4. YANG Module
This module references [RFC7752], [RFC8345], [RFC8346], [RFC8476],
[RFC8491], [RFC8665], [RFC8666], [RFC8667], [RFC8814], [RFC9020], and
[I-D.ietf-idr-bgp-ls-segment-routing-ext].
<CODE BEGINS> file "ietf-sr-mpls-topology@2021-10-23.yang"
module ietf-sr-mpls-topology {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-sr-mpls-topology";
prefix "srmt";
import ietf-network {
prefix "nw";
reference "RFC 8345: A YANG Data Model for Network Topologies";
}
import ietf-network-topology {
prefix "nt";
reference "RFC 8345: A YANG Data Model for Network Topologies";
}
import ietf-l3-unicast-topology {
prefix "l3t";
reference "RFC 8346: A YANG Data Model for Layer 3 Topologies";
}
import ietf-segment-routing-common {
prefix "sr-cmn";
reference "RFC 9020: YANG Data Model for Segment Routing";
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}
organization
"IETF Traffic Engineering Architecture and Signaling (TEAS)
Working Group";
contact
"WG Web: <http://tools.ietf.org/wg/teas/>
WG List: <mailto:teas@ietf.org>
Editor: Xufeng Liu
<mailto:xufeng.liu.ietf@gmail.com>
Editor: Igor Bryskin
<mailto:Igor.Bryskin@huawei.com>
Editor: Vishnu Pavan Beeram
<mailto:vbeeram@juniper.net>
Editor: Tarek Saad
<mailto:tsaad@cisco.com>
Editor: Himanshu Shah
<mailto:hshah@ciena.com>
Editor: Stephane Litkowski
<mailto:stephane.litkowski@orange.com>";
description
"YANG data model for representing and manipulating Segment
Routing Topologies on MPLS Data Plane.
Copyright (c) 2021 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
(http://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX; see the
RFC itself for full legal notices.";
revision 2021-10-23 {
description "Initial revision";
reference
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"RFC XXXX: YANG Data Model for SR and SR TE Topologies on MPLS
Data Plane";
}
identity msd-base-type {
description
"Base identity for MSD Type";
}
identity base-mpls-msd {
base msd-base-type;
description
"Base MPLS Imposition MSD.";
reference
"RFC 8491: Signaling Maximum SID Depth (MSD) Using IS-IS";
}
identity erld-msd {
base msd-base-type;
description
"ERLD-MSD is defined to advertise the ERLD.";
reference
"RFC 8662: Entropy Label for Source Packet Routing in
Networking (SPRING) Tunnels";
}
feature msd {
description
"Support of signaling MSD (Maximum SID Depth) in IGP.";
reference
"RFC 8476: Signaling Maximum SID Depth (MSD) Using OSPF.
RFC 8491: Signaling Maximum SID Depth (MSD) Using IS-IS.
RFC 8814: Signaling Maximum SID Depth (MSD) Using the Border
Gateway Protocol - Link State.";
}
grouping sr-mpls-topology-type {
description
"Identifies the SR-MPLS topology type. This type of network
topologies use Segment Routing (SR) technology over the MPLS
data plane";
container sr-mpls {
presence "Indicates SR-MPLS topology";
description
"Its presence identifies the SR MPLS topology type.";
}
}
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augment "/nw:networks/nw:network/nw:network-types/"
+ "l3t:l3-unicast-topology" {
description
"Defines the SR MPLS topology type.";
uses sr-mpls-topology-type;
}
augment "/nw:networks/nw:network/l3t:l3-topology-attributes" {
when "../nw:network-types/l3t:l3-unicast-topology/srmt:sr-mpls" {
description "Augment only for SR MPLS topology.";
}
description "Augment topology configuration";
uses sr-mpls-topology-attributes;
}
augment "/nw:networks/nw:network/nw:node/l3t:l3-node-attributes" {
when "../../nw:network-types/l3t:l3-unicast-topology/"
+ "srmt:sr-mpls" {
description "Augment only for SR MPLS topology.";
}
description "Augment node configuration.";
uses sr-node-attributes;
}
augment "/nw:networks/nw:network/nw:node/l3t:l3-node-attributes"
+ "/l3t:prefix" {
when "../../../nw:network-types/l3t:l3-unicast-topology/"
+ "srmt:sr-mpls" {
description "Augment only for SR MPLS topology.";
}
description "Augment node prefix.";
uses sr-node-prefix-attributes;
}
augment "/nw:networks/nw:network/nt:link/l3t:l3-link-attributes" {
when "../../nw:network-types/l3t:l3-unicast-topology/"
+ "srmt:sr-mpls" {
description "Augment only for SR MPLS topology.";
}
description "Augment link configuration";
uses sr-link-attributes;
}
grouping sr-mpls-topology-attributes {
description "SR MPLS topology scope attributes.";
container sr-mpls {
description
"Containing SR attributes.";
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uses sr-cmn:srgb;
} // sr
} // sr-mpls-topology-attributes
grouping information-source-attributes {
description
"The attributes identifying source that has provided the
related information, and the source credibility.";
leaf information-source {
type enumeration {
enum "unknown" {
description "The source is unknown.";
}
enum "locally-configured" {
description "Configured entity.";
}
enum "ospfv2" {
description "OSPFv2.";
reference
"RFC 8665: OSPF Extensions for Segment Routing.";
}
enum "ospfv3" {
description "OSPFv3.";
reference
"RFC 8666: OSPFv3 Extensions for Segment Routing.";
}
enum "isis" {
description "ISIS.";
reference
"RFC 8667: IS-IS Extensions for Segment Routing.";
}
enum "bgp-ls" {
description "BGP-LS.";
reference
"RFC 7752: North-Bound Distribution of Link-State and
Traffic Engineering (TE) Information Using BGP.
I-D.ietf-idr-bgp-ls-segment-routing-ext:
BGP Link-State extensions for Segment Routing.";
}
enum "system-processed" {
description "System processed entity.";
}
enum "other" {
description "Other source.";
}
}
config false;
description
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"Indicates the type of the information source.";
}
leaf information-source-instance {
type string;
config false;
description
"The name indicating the instance of the information
source.";
}
container information-source-state {
config false;
description
"The container contains state attributes related to
the information source.";
leaf credibility-preference {
type uint16;
description
"The preference value to calculate the traffic
engineering database credibility value used for
tie-break selection between different
information-source values.
Higher value is more preferable.";
}
}
} // information-source-attributes
grouping sr-node-attributes {
description "SR node scope attributes.";
container sr-mpls {
presence "Presence indicates SR is enabled.";
description
"Containing SR attributes.";
uses sr-cmn:srgb;
uses sr-cmn:srlb;
container msds {
if-feature "msd";
description
"MSDs on the node.";
list node-msd {
key "msd-type";
leaf msd-type {
type identityref {
base msd-base-type;
}
description
"MSD Type.";
}
leaf msd-value {
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type uint8;
description
"MSD value, in the range of 0-255. Node MSD is the
lowest MSD supported by the node.";
}
description
"List of node MSDs. A node may have a list of MSD values,
with at most one value for each msd-type.";
reference
"RFC 8491: Signaling Maximum SID Depth (MSD) Using
IS-IS";
}
}
// Operational state data
uses information-source-attributes;
} // sr
} // sr-node-attributes
grouping sr-node-prefix-attributes {
description "Containing SR attributes for a prefix.";
container sr-mpls {
presence "Presence indicates SR is enabled.";
description
"Containing SR attributes for a prefix.";
container sids {
description
"Containing Prefix SIDs assigned to this prefix.";
list sid {
key "algorithm";
description
"A list of SIDs with their properties.";
uses sr-cmn:prefix-sid-attributes;
uses sr-cmn:last-hop-behavior;
leaf is-local {
type boolean;
default false;
description
"'true' if the SID is local.";
}
leaf is-node {
type boolean;
default false;
description
"'true' if the Prefix-SID refers to the router
identified by the prefix. Typically, the leaf
'is-node' (N-Flag) is set on Prefix-SIDs attached to a
router loopback address.";
}
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leaf is-readvertisment {
type boolean;
config false;
description
"'true' if the prefix to which this Prefix-SID is
attached, has been propagated by the router from
another topology by redistribution.";
reference
"RFC 8667: IS-IS Extensions for Segment Routing.
Sec 2.1.";
}
}
}
} // sr
} // sr-node-prefix-attributes
grouping sr-link-attributes {
description "SR link scope attributes";
container sr-mpls {
presence "Presence indicates SR is enabled.";
description
"Containing SR attributes.";
container msds {
if-feature "msd";
description
"MSDs on the link.";
list link-msd {
key "msd-type";
leaf msd-type {
type identityref {
base msd-base-type;
}
description
"MSD Type.";
}
leaf msd-value {
type uint8;
description
"MSD value, in the range of 0-255.";
}
description
"List of link MSDs. A link may have a list of MSD values,
with at most one value for each msd-type.";
reference
"RFC 8491: Signaling Maximum SID Depth (MSD) Using
IS-IS";
}
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}
container sids {
description
"Containing Adjacency SIDs assigned to this link.";
list sid {
key "value-type sid";
description
"A list of SIDs with their properties.";
uses sr-cmn:sid-value-type;
leaf sid {
type uint32;
mandatory true;
description
"Adjacency SID, which can be either IGP-Adjacency SID
or BGP PeerAdj SID, depending on the context.";
}
leaf address-family {
type enumeration {
enum "ipv4" {
description
"The Adj-SID refers to an adjacency with outgoing
IPv4 encapsulation.";
}
enum "ipv6" {
description
"The Adj-SID refers to an adjacency with outgoing
IPv6 encapsulation.";
}
}
default "ipv4";
description
"This leaf defines the F-Flag (Address-Family flag) of
the SID.";
}
leaf is-eligible-for-protection {
type boolean;
default false;
description
"'true' if the SID is is eligible for protection.";
reference
"RFC 8402: Segment Routing Architecture. Sec. 3.4.";
}
leaf is-local {
type boolean;
default false;
description
"'true' if the SID is local.";
}
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leaf is-part-of-set {
type boolean;
default false;
description
"'true' if the SID is part of a set.";
}
leaf is-persistent {
type boolean;
default true;
description
"'true' if the SID is persistently allocated.";
}
leaf is-on-lan {
type boolean;
default false;
description
"'true' if on a lan.";
}
leaf weight {
type uint8;
description
"The value represents the weight of the SID for the
purpose of load balancing. The use of the weight
is defined in RFC 8402.";
reference
"RFC 8402: Segment Routing Architecture. Sec. 3.4.";
}
}
}
uses information-source-attributes;
} // sr
} // sr-tp-attributes
}
<CODE ENDS>
5. IANA Considerations
RFC Ed.: In this section, replace all occurrences of 'XXXX' with the
actual RFC number (and remove this note).
This document registers the following namespace URIs in the IETF XML
registry [RFC3688]:
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--------------------------------------------------------------------
URI: urn:ietf:params:xml:ns:yang:ietf-sr-mpls-topology
Registrant Contact: The IESG.
XML: N/A, the requested URI is an XML namespace.
--------------------------------------------------------------------
--------------------------------------------------------------------
URI: urn:ietf:params:xml:ns:yang:ietf-sr-mpls-topology-state
Registrant Contact: The IESG.
XML: N/A, the requested URI is an XML namespace.
--------------------------------------------------------------------
This document registers the following YANG modules in the YANG Module
Names registry [RFC6020]:
--------------------------------------------------------------------
name: ietf-sr-mpls-topology
namespace: urn:ietf:params:xml:ns:yang:ietf-sr-mpls-topology
prefix: srmt
reference: RFC XXXX
--------------------------------------------------------------------
--------------------------------------------------------------------
name: ietf-sr-mpls-topology-state
namespace: urn:ietf:params:xml:ns:yang:ietf-sr-mpls-topology-state
prefix: srmt-s
reference: RFC XXXX
--------------------------------------------------------------------
6. Security Considerations
The YANG module specified in this document defines a schema for data
that is designed to be accessed via network management protocols such
as NETCONF [RFC6241] or RESTCONF [RFC8040]. The lowest NETCONF layer
is the secure transport layer, and the mandatory-to-implement secure
transport is Secure Shell (SSH) [RFC6242]. The lowest RESTCONF layer
is HTTPS, and the mandatory-to-implement secure transport is TLS
[RFC8446].
The Network Configuration Access Control Model (NACM) [RFC8341]
provides the means to restrict access for particular NETCONF or
RESTCONF users to a preconfigured subset of all available NETCONF or
RESTCONF protocol operations and content.
There are a number of data nodes defined in 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)
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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:
/nw:networks/nw:network/nw:network-types/l3t:l3-unicast-topology/sr-
mpls
This subtree specifies the SR MPLS topology type. Modifying the
configurations can make SR MPLS topology type invalid and cause
interruption to all SR networks.
/nw:networks/nw:network/l3t:l3-topology-attributes/sr
This subtree specifies the topology-wide configurations, including
the SRGB (Segment Routing Global Block). Modifying the
configurations here can cause traffic disabled or rerouted in this
topology and the connected topologies.
/nw:networks/nw:network/nw:node/l3t:l3-node-attributes
This subtree specifies the SR configurations for nodes. Modifying
the configurations in this subtree can add, remove, or modify SR
nodes, causing traffic disabled or rerouted in the specified nodes
and the related TE topologies.
/nw:networks/nw:network/nt:link/l3t:l3-link-attributes/sr
This subtree specifies the configurations for SR Adjacency
Segments. Modifying the configurations in this subtree can add,
remove, or modify SR Adjacency Segments causing traffic disabled
or rerouted on the specified SR adjacencies, the related nodes,
and the related SR MPLS topologies.
Some of the readable data nodes in 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:
/nw:networks/nw:network/nw:network-types/l3t:l3-unicast-topology/sr-
mpls
Unauthorized access to this subtree can disclose the SR MPLS
topology type.
/nw:networks/nw:network/l3t:l3-topology-attributes/sr
Unauthorized access to this subtree can disclose the topology-wide
configurations, including the SRGB (Segment Routing Global Block).
/nw:networks/nw:network/nw:node/l3t:l3-node-attributes
Unauthorized access to this subtree can disclose the operational
state information of the SR nodes.
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/nw:networks/nw:network/nt:link/l3t:l3-link-attributes/sr
Unauthorized access to this subtree can disclose the operational
state information of SR Adjacency Segments.
7. References
7.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[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>.
[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>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[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>.
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[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>.
[RFC8345] Clemm, A., Medved, J., Varga, R., Bahadur, N.,
Ananthakrishnan, H., and X. Liu, "A YANG Data Model for
Network Topologies", RFC 8345, DOI 10.17487/RFC8345, March
2018, <https://www.rfc-editor.org/info/rfc8345>.
[RFC8346] Clemm, A., Medved, J., Varga, R., Liu, X.,
Ananthakrishnan, H., and N. Bahadur, "A YANG Data Model
for Layer 3 Topologies", RFC 8346, DOI 10.17487/RFC8346,
March 2018, <https://www.rfc-editor.org/info/rfc8346>.
[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>.
[RFC8476] Tantsura, J., Chunduri, U., Aldrin, S., and P. Psenak,
"Signaling Maximum SID Depth (MSD) Using OSPF", RFC 8476,
DOI 10.17487/RFC8476, December 2018,
<https://www.rfc-editor.org/info/rfc8476>.
[RFC8491] Tantsura, J., Chunduri, U., Aldrin, S., and L. Ginsberg,
"Signaling Maximum SID Depth (MSD) Using IS-IS", RFC 8491,
DOI 10.17487/RFC8491, November 2018,
<https://www.rfc-editor.org/info/rfc8491>.
[RFC8814] Tantsura, J., Chunduri, U., Talaulikar, K., Mirsky, G.,
and N. Triantafillis, "Signaling Maximum SID Depth (MSD)
Using the Border Gateway Protocol - Link State", RFC 8814,
DOI 10.17487/RFC8814, August 2020,
<https://www.rfc-editor.org/info/rfc8814>.
[RFC9020] Litkowski, S., Qu, Y., Lindem, A., Sarkar, P., and J.
Tantsura, "YANG Data Model for Segment Routing", RFC 9020,
DOI 10.17487/RFC9020, May 2021,
<https://www.rfc-editor.org/info/rfc9020>.
[I-D.ietf-teas-yang-l3-te-topo]
Liu, X., Bryskin, I., Beeram, V. P., Saad, T., Shah, H.,
and O. G. D. Dios, "YANG Data Model for Layer 3 TE
Topologies", draft-ietf-teas-yang-l3-te-topo-12 (work in
progress), October 2021.
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7.2. Informative References
[RFC7752] Gredler, H., Ed., Medved, J., Previdi, S., Farrel, A., and
S. Ray, "North-Bound Distribution of Link-State and
Traffic Engineering (TE) Information Using BGP", RFC 7752,
DOI 10.17487/RFC7752, March 2016,
<https://www.rfc-editor.org/info/rfc7752>.
[RFC7951] Lhotka, L., "JSON Encoding of Data Modeled with YANG",
RFC 7951, DOI 10.17487/RFC7951, August 2016,
<https://www.rfc-editor.org/info/rfc7951>.
[RFC8340] Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams",
BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018,
<https://www.rfc-editor.org/info/rfc8340>.
[RFC8665] Psenak, P., Ed., Previdi, S., Ed., Filsfils, C., Gredler,
H., Shakir, R., Henderickx, W., and J. Tantsura, "OSPF
Extensions for Segment Routing", RFC 8665,
DOI 10.17487/RFC8665, December 2019,
<https://www.rfc-editor.org/info/rfc8665>.
[RFC8666] Psenak, P., Ed. and S. Previdi, Ed., "OSPFv3 Extensions
for Segment Routing", RFC 8666, DOI 10.17487/RFC8666,
December 2019, <https://www.rfc-editor.org/info/rfc8666>.
[RFC8667] Previdi, S., Ed., Ginsberg, L., Ed., Filsfils, C.,
Bashandy, A., Gredler, H., and B. Decraene, "IS-IS
Extensions for Segment Routing", RFC 8667,
DOI 10.17487/RFC8667, December 2019,
<https://www.rfc-editor.org/info/rfc8667>.
[RFC8795] Liu, X., Bryskin, I., Beeram, V., Saad, T., Shah, H., and
O. Gonzalez de Dios, "YANG Data Model for Traffic
Engineering (TE) Topologies", RFC 8795,
DOI 10.17487/RFC8795, August 2020,
<https://www.rfc-editor.org/info/rfc8795>.
[I-D.ietf-idr-bgp-ls-segment-routing-ext]
Previdi, S., Talaulikar, K., Filsfils, C., Gredler, H.,
and M. Chen, "Border Gateway Protocol - Link State (BGP-
LS) Extensions for Segment Routing", draft-ietf-idr-bgp-
ls-segment-routing-ext-18 (work in progress), April 2021.
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Appendix A. Companion YANG Model for Non-NMDA Compliant Implementations
The YANG module ietf-sr-mpls-topology defined in this document is
designed to be used in conjunction with implementations that support
the Network Management Datastore Architecture (NMDA) defined in
[RFC8342]. In order to allow implementations to use the model even
in cases when NMDA is not supported, the following companion module,
ietf-sr-mpls-topology-state, is defined as state model, which mirrors
the module ietf-sr-mpls-topology defined earlier in this document.
However, all data nodes in the companion module are non-configurable,
to represent the applied configuration or the derived operational
states.
The companion module, ietf-sr-mpls-topology-state, is redundant and
SHOULD NOT be supported by implementations that support NMDA.
As the structure of the companion module mirrors that of the
coorespinding NMDA model, the YANG tree of the companion module is
not depicted separately.
A.1. SR MPLS Topology State Module
This module references [RFC8345] and [RFC8346].
<CODE BEGINS> file "ietf-sr-mpls-topology-state@2021-10-23.yang"
module ietf-sr-mpls-topology-state {
yang-version 1.1;
namespace
"urn:ietf:params:xml:ns:yang:ietf-sr-mpls-topology-state";
prefix "srmt-s";
import ietf-sr-mpls-topology {
prefix "srmt";
}
import ietf-network-state {
prefix "nw-s";
reference "RFC 8345: A YANG Data Model for Network Topologies";
}
import ietf-network-topology-state {
prefix "nt-s";
reference "RFC 8345: A YANG Data Model for Network Topologies";
}
import ietf-l3-unicast-topology-state {
prefix "l3t-s";
reference "RFC 8346: A YANG Data Model for Layer 3 Topologies";
}
import ietf-segment-routing-common {
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prefix "sr-cmn";
reference "RFC 9020: YANG Data Model for Segment Routing";
}
organization
"IETF Traffic Engineering Architecture and Signaling (TEAS)
Working Group";
contact
"WG Web: <http://tools.ietf.org/wg/teas/>
WG List: <mailto:teas@ietf.org>
Editor: Xufeng Liu
<mailto:xufeng.liu.ietf@gmail.com>
Editor: Igor Bryskin
<mailto:Igor.Bryskin@huawei.com>
Editor: Vishnu Pavan Beeram
<mailto:vbeeram@juniper.net>
Editor: Tarek Saad
<mailto:tsaad@cisco.com>
Editor: Himanshu Shah
<mailto:hshah@ciena.com>
Editor: Stephane Litkowski
<mailto:stephane.litkowski@orange.com>";
description
"YANG data model for representing operational state information
of Segment Routing Topologies on MPLS data plane, when NMDA is
not supported.
Copyright (c) 2021 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
(http://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX; see the
RFC itself for full legal notices.";
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revision 2021-10-23 {
description "Initial revision";
reference
"RFC XXXX: YANG Data Model for SR and SR TE Topologies on MPLS
Data Plane";
}
augment "/nw-s:networks/nw-s:network/nw-s:network-types/"
+ "l3t-s:l3-unicast-topology" {
description
"Defines the SR MPLS topology type.";
uses srmt:sr-mpls-topology-type;
}
augment "/nw-s:networks/nw-s:network/"
+ "l3t-s:l3-topology-attributes" {
when "../nw-s:network-types/l3t-s:l3-unicast-topology/"
+ "srmt-s:sr-mpls" {
description "Augment only for SR MPLS topology.";
}
description "Augment topology configuration";
uses srmt:sr-mpls-topology-attributes;
}
augment "/nw-s:networks/nw-s:network/nw-s:node/"
+ "l3t-s:l3-node-attributes" {
when "../../nw-s:network-types/l3t-s:l3-unicast-topology/"
+ "srmt-s:sr-mpls" {
description "Augment only for SR MPLS topology.";
}
description "Augment node configuration.";
uses srmt:sr-node-attributes;
}
augment "/nw-s:networks/nw-s:network/nw-s:node/"
+ "l3t-s:l3-node-attributes/l3t-s:prefix" {
when "../../../nw-s:network-types/l3t-s:l3-unicast-topology/"
+ "srmt-s:sr-mpls" {
description "Augment only for SR MPLS topology.";
}
description "Augment node prefix.";
uses srmt:sr-node-prefix-attributes;
}
augment "/nw-s:networks/nw-s:network/nt-s:link/"
+ "l3t-s:l3-link-attributes" {
when "../../nw-s:network-types/l3t-s:l3-unicast-topology/"
+ "srmt-s:sr-mpls" {
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description "Augment only for SR MPLS topology.";
}
description "Augment link configuration";
uses srmt:sr-link-attributes;
}
grouping sr-mpls-topology-attributes {
description "SR MPLS topology scope attributes.";
container sr-mpls {
description
"Containing SR attributes.";
uses sr-cmn:srgb;
} // sr
} // sr-mpls-topology-attributes
}
<CODE ENDS>
Appendix B. Data Tree Example
This section contains an example of an instance data tree in the JSON
encoding [RFC7951]. The example instantiates "ietf-sr-mpls-topology"
for the topology that is depicted in the following diagram.
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router-id: 203.0.113.1 router-id: 203.0.113.2
+------------+ +------------+
| D1 | | D2 |
/-\ /-\ /-\ /-\
| | 1-0-1 | |---------------->| | 2-1-1 | |
| | 1-2-1 | |<----------------| | 2-0-1 | |
\-/ 1-3-1 \-/ \-/ 2-3-1 \-/
| /----\ | | /----\ |
+---| |---+ +---| |---+
\----/ \----/
A | A |
| | | |
| | router-id: 203.0.113.3 | |
| | +------------+ | |
| | | D3 | | |
| | /-\ /-\ | |
| +----->| | 3-1-1 | |-------+ |
+---------| | 3-2-1 | |<---------+
\-/ \-/
| |
+------------+
Figure 4: Example SR MPLS Topology
The corresponding instance data tree is depicted below. Note that
some lines have been wrapped to adhere to the 72-character line
limitation of RFCs.
B.1. SR MPLS Topology with TE Not Enabled
{
"ietf-network:networks": {
"network": [
{
"network-types": {
"ietf-l3-unicast-topology:l3-unicast-topology": {
"ietf-sr-mpls-topology:sr-mpls": {}
}
},
"network-id": "sr-mpls-topo-example",
"ietf-l3-unicast-topology:l3-topology-attributes": {
"ietf-sr-mpls-topology:sr-mpls": {
"srgb": [
{
"lower-bound": 16000,
"upper-bound": 23999
}
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]
}
},
"node": [
{
"node-id": "D1",
"ietf-network-topology:termination-point": [
{
"tp-id": "1-0-1",
"ietf-l3-unicast-topology:l3-termination-point-attributes": {
"unnumbered-id": 101
}
},
{
"tp-id": "1-2-1",
"ietf-l3-unicast-topology:l3-termination-point-attributes": {
"unnumbered-id": 121
}
},
{
"tp-id": "1-3-1",
"ietf-l3-unicast-topology:l3-termination-point-attributes": {
"unnumbered-id": 131
}
}
],
"ietf-l3-unicast-topology:l3-node-attributes": {
"router-id": ["203.0.113.1"],
"prefix": [
{
"prefix": "203.0.113.1/32",
"ietf-sr-mpls-topology:sr-mpls": {
"sids": {
"sid": [
{
"algorithm": "prefix-sid-algorithm-shortest-path",
"start-sid": 101,
"range": 1,
"is-local": false,
"is-node": true
}
]
}
}
}
],
"ietf-sr-mpls-topology:sr-mpls": {
"srgb": [
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{
"lower-bound": 16000,
"upper-bound": 23999
}
],
"srlb": [
{
"lower-bound": 15000,
"upper-bound": 15999
}
]
}
}
},
{
"node-id": "D2",
"ietf-network-topology:termination-point": [
{
"tp-id": "2-0-1",
"ietf-l3-unicast-topology:l3-termination-point-attributes": {
"unnumbered-id": 201
}
},
{
"tp-id": "2-1-1",
"ietf-l3-unicast-topology:l3-termination-point-attributes": {
"unnumbered-id": 211
}
},
{
"tp-id": "2-3-1",
"ietf-l3-unicast-topology:l3-termination-point-attributes": {
"unnumbered-id": 231
}
}
],
"ietf-l3-unicast-topology:l3-node-attributes": {
"router-id": ["203.0.113.2"],
"prefix": [
{
"prefix": "203.0.113.2/32",
"ietf-sr-mpls-topology:sr-mpls": {
"sids": {
"sid": [
{
"algorithm": "prefix-sid-algorithm-shortest-path",
"start-sid": 102,
"range": 1,
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"is-local": false,
"is-node": true
}
]
}
}
}
],
"ietf-sr-mpls-topology:sr-mpls": {
"srgb": [
{
"lower-bound": 16000,
"upper-bound": 23999
}
],
"srlb": [
{
"lower-bound": 15000,
"upper-bound": 15999
}
]
}
}
},
{
"node-id": "D3",
"ietf-network-topology:termination-point": [
{
"tp-id": "3-1-1",
"ietf-l3-unicast-topology:l3-termination-point-attributes": {
"unnumbered-id": 311
}
},
{
"tp-id": "3-2-1",
"ietf-l3-unicast-topology:l3-termination-point-attributes": {
"unnumbered-id": 321
}
}
],
"ietf-l3-unicast-topology:l3-node-attributes": {
"router-id": ["203.0.113.3"],
"prefix": [
{
"prefix": "203.0.113.3/32",
"ietf-sr-mpls-topology:sr-mpls": {
"sids": {
"sid": [
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{
"algorithm": "prefix-sid-algorithm-shortest-path",
"start-sid": 103,
"range": 1,
"is-local": false,
"is-node": true
}
]
}
}
}
],
"ietf-sr-mpls-topology:sr-mpls": {
"srgb": [
{
"lower-bound": 16000,
"upper-bound": 23999
}
],
"srlb": [
{
"lower-bound": 15000,
"upper-bound": 15999
}
]
}
}
}
],
"ietf-network-topology:link": [
{
"link-id": "D1,1-2-1,D2,2-1-1",
"source": {
"source-node": "D1",
"source-tp": "1-2-1"
},
"destination": {
"dest-node": "D2",
"dest-tp": "2-1-1"
},
"ietf-l3-unicast-topology:l3-link-attributes": {
"metric1": "100",
"ietf-sr-mpls-topology:sr-mpls": {
"sids": {
"sid": [
{
"value-type": "index",
"sid": 121,
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"is-local": true
}
]
}
}
}
},
{
"link-id": "D2,2-1-1,D1,1-2-1",
"source": {
"source-node": "D2",
"source-tp": "2-1-1"
},
"destination": {
"dest-node": "D1",
"dest-tp": "1-2-1"
},
"ietf-l3-unicast-topology:l3-link-attributes": {
"metric1": "100",
"ietf-sr-mpls-topology:sr-mpls": {
"sids": {
"sid": [
{
"value-type": "index",
"sid": 211,
"is-local": true
}
]
}
}
}
},
{
"link-id": "D1,1-3-1,D3,3-1-1",
"source": {
"source-node": "D1",
"source-tp": "1-3-1"
},
"destination": {
"dest-node": "D3",
"dest-tp": "3-1-1"
},
"ietf-l3-unicast-topology:l3-link-attributes": {
"metric1": "100",
"ietf-sr-mpls-topology:sr-mpls": {
"sids": {
"sid": [
{
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"value-type": "index",
"sid": 131,
"is-local": true
}
]
}
}
}
},
{
"link-id": "D3,3-1-1,D1,1-3-1",
"source": {
"source-node": "D3",
"source-tp": "3-1-1"
},
"destination": {
"dest-node": "D1",
"dest-tp": "1-3-1"
},
"ietf-l3-unicast-topology:l3-link-attributes": {
"metric1": "100",
"ietf-sr-mpls-topology:sr-mpls": {
"sids": {
"sid": [
{
"value-type": "index",
"sid": 311,
"is-local": true
}
]
}
}
}
},
{
"link-id": "D2,2-3-1,D3,3-2-1",
"source": {
"source-node": "D2",
"source-tp": "2-3-1"
},
"destination": {
"dest-node": "D3",
"dest-tp": "3-2-1"
},
"ietf-l3-unicast-topology:l3-link-attributes": {
"metric1": "100",
"ietf-sr-mpls-topology:sr-mpls": {
"sids": {
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"sid": [
{
"value-type": "index",
"sid": 231,
"is-local": true
}
]
}
}
}
},
{
"link-id": "D3,3-2-1,D2,2-3-1",
"source": {
"source-node": "D3",
"source-tp": "3-2-1"
},
"destination": {
"dest-node": "D2",
"dest-tp": "2-3-1"
},
"ietf-l3-unicast-topology:l3-link-attributes": {
"metric1": "100",
"ietf-sr-mpls-topology:sr-mpls": {
"sids": {
"sid": [
{
"value-type": "index",
"sid": 321,
"is-local": true
}
]
}
}
}
}
]
}
]
}
}
B.2. SR MPLS Topology with TE Enabled
In this section, the example below shows an instance data of a
overlay topology as shown in Figure 4. Some attributes are from the
underlay topology shown in Figure 5.
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............................. ....................
. D1 . . D2 .
. . . .
. SID:17012 . . .
. Base64:MTcwMTI= . . .
. +---+ +---+ +---+ . . +---+ +---+ .
-----|S11|----|S12|----|S15|---------|S23|----|S25|-----
. +---+\ +---+ /+---+ . . +---+ /+---+ .
. \ / . . / | .
. \ / . . / | .
. \+---+/ . . +---+/ +---+ .
. |S14| . . |S24|----|S28| .
. +---+ . . +---+ +---+ .
..............|.............. .....|..............
| |
SID:17051 +---+ +---+ SID:17052 |
Base64: |S51|----|S52| Base64: |
MTcwNTE= +---+ /+---+ MTcwNTI= |
| / /
| / .........../
| / . D3 /
| / . /.
SID:17053 +---+ . +---+/ .
Base64: |S53|-----------|S31| .
MTcwNTM= +---+ . +---+ .
...........
Figure 5: Example Underlay SR MPLS TE Toplogy
{
"ietf-network:networks": {
"network": [
{
"network-types": {
"ietf-l3-unicast-topology:l3-unicast-topology": {
"ietf-sr-mpls-topology:sr-mpls": {}
},
"ietf-te-topology:te-topology": {
"ietf-te-topology-packet:packet": {}
}
},
"network-id": "sr-mpls-te-topo-example",
"ietf-l3-unicast-topology:l3-topology-attributes": {
"ietf-sr-mpls-topology:sr-mpls": {
"srgb": [
{
"lower-bound": 16000,
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"upper-bound": 23999
}
]
}
},
"ietf-te-topology:te-topology-identifier": {
"provider-id": 0,
"client-id": 0,
"topology-id": "sr-mpls-te-topo-example"
},
"ietf-te-topology:te": {
"optimization-criterion": "ietf-te-types:of-minimize-cost-path"
},
"node": [
{
"node-id": "D1",
"ietf-network-topology:termination-point": [
{
"tp-id": "1-0-1",
"ietf-l3-unicast-topology:l3-termination-point-attributes": {
"unnumbered-id": 101
},
"ietf-te-topology:te-tp-id": 101,
"ietf-te-topology:te": {
"interface-switching-capability": [
{
"switching-capability": "switching-psc1",
"encoding": "lsp-encoding-packet",
"max-lsp-bandwidth": [
{
"priority": 7,
"te-bandwidth": {
"generic": "0x1p22"
}
}
]
}
]
}
},
{
"tp-id": "1-2-1",
"ietf-l3-unicast-topology:l3-termination-point-attributes": {
"unnumbered-id": 121
},
"ietf-te-topology:te-tp-id": 121,
"ietf-te-topology:te": {
"interface-switching-capability": [
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{
"switching-capability": "switching-psc1",
"encoding": "lsp-encoding-packet",
"max-lsp-bandwidth": [
{
"priority": 7,
"te-bandwidth": {
"generic": "0x1p22"
}
}
]
}
]
}
},
{
"tp-id": "1-3-1",
"ietf-l3-unicast-topology:l3-termination-point-attributes": {
"unnumbered-id": 131
},
"ietf-te-topology:te-tp-id": 131,
"ietf-te-topology:te": {
"interface-switching-capability": [
{
"switching-capability": "switching-psc1",
"encoding": "lsp-encoding-packet",
"max-lsp-bandwidth": [
{
"priority": 7,
"te-bandwidth": {
"generic": "0x1p22"
}
}
]
}
]
}
}
],
"ietf-l3-unicast-topology:l3-node-attributes": {
"router-id": ["203.0.113.1"],
"prefix": [
{
"prefix": "203.0.113.1/32",
"ietf-sr-mpls-topology:sr-mpls": {
"sids": {
"sid": [
{
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"algorithm": "prefix-sid-algorithm-shortest-path",
"start-sid": 101,
"range": 1,
"is-local": false,
"is-node": true
}
]
}
}
}
],
"ietf-sr-mpls-topology:sr-mpls": {
"srgb": [
{
"lower-bound": 16000,
"upper-bound": 23999
}
],
"srlb": [
{
"lower-bound": 15000,
"upper-bound": 15999
}
]
}
},
"ietf-te-topology:te-node-id": "203.0.113.1",
"ietf-te-topology:te": {
"te-node-attributes": {
"admin-status": "up",
"domain-id": 1001,
"is-abstract": [null],
"signaling-address": [
"203.0.113.1"
],
"connectivity-matrices": {
"is-allowed": true,
"path-constraints": {
"te-bandwidth": {
"generic": "0x1p20"
},
"path-metric-bounds": {
"path-metric-bound": [
{
"metric-type": "path-metric-delay-average",
"upper-bound": 15000
}
]
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}
},
"ietf-te-topology-packet:throttle": {
"threshold-out": {
"two-way-delay": 18000
}
},
"connectivity-matrix": [
{
"id": 1,
"from": {
"tp-ref": "1-0-1"
},
"to": {
"tp-ref": "1-2-1"
},
"is-allowed": true,
"underlay": {
"enabled": true,
"primary-path": {
"network-ref": "underlay-example",
"path-element": [
{
"path-element-id": 1,
"label-hop": {
"te-label": {
"generic": "MTcwMTI=",
"direction": "forward"
}
}
}
]
}
}
},
{
"id": 2,
"from": {
"tp-ref": "1-2-1"
},
"to": {
"tp-ref": "1-0-1"
},
"is-allowed": true,
"underlay": {
"enabled": true,
"primary-path": {
"network-ref": "underlay-example",
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"path-element": [
{
"path-element-id": 1,
"label-hop": {
"te-label": {
"generic": "MTcwMTI=",
"direction": "forward"
}
}
}
]
}
}
}
]
}
}
}
},
{
"node-id": "D2",
"ietf-network-topology:termination-point": [
{
"tp-id": "2-0-1",
"ietf-l3-unicast-topology:l3-termination-point-attributes": {
"unnumbered-id": 201
},
"ietf-te-topology:te-tp-id": 201,
"ietf-te-topology:te": {
"interface-switching-capability": [
{
"switching-capability": "switching-psc1",
"encoding": "lsp-encoding-packet",
"max-lsp-bandwidth": [
{
"priority": 7,
"te-bandwidth": {
"generic": "0x1p22"
}
}
]
}
]
}
},
{
"tp-id": "2-1-1",
"ietf-l3-unicast-topology:l3-termination-point-attributes": {
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"unnumbered-id": 211
},
"ietf-te-topology:te-tp-id": 211,
"ietf-te-topology:te": {
"interface-switching-capability": [
{
"switching-capability": "switching-psc1",
"encoding": "lsp-encoding-packet",
"max-lsp-bandwidth": [
{
"priority": 7,
"te-bandwidth": {
"generic": "0x1p22"
}
}
]
}
]
}
},
{
"tp-id": "2-3-1",
"ietf-l3-unicast-topology:l3-termination-point-attributes": {
"unnumbered-id": 231
}
}
],
"ietf-l3-unicast-topology:l3-node-attributes": {
"router-id": ["203.0.113.2"],
"prefix": [
{
"prefix": "203.0.113.2/32",
"ietf-sr-mpls-topology:sr-mpls": {
"sids": {
"sid": [
{
"algorithm": "prefix-sid-algorithm-shortest-path",
"start-sid": 102,
"range": 1,
"is-local": false,
"is-node": true
}
]
}
}
}
],
"ietf-sr-mpls-topology:sr-mpls": {
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"srgb": [
{
"lower-bound": 16000,
"upper-bound": 23999
}
],
"srlb": [
{
"lower-bound": 15000,
"upper-bound": 15999
}
]
}
},
"ietf-te-topology:te-node-id": "203.0.113.2",
"ietf-te-topology:te": {
"te-node-attributes": {
"admin-status": "up",
"domain-id": 1001,
"is-abstract": [null],
"signaling-address": [
"203.0.113.2"
]
}
}
},
{
"node-id": "D3",
"ietf-network-topology:termination-point": [
{
"tp-id": "3-1-1",
"ietf-l3-unicast-topology:l3-termination-point-attributes": {
"unnumbered-id": 311
},
"ietf-te-topology:te-tp-id": 311,
"ietf-te-topology:te": {
"interface-switching-capability": [
{
"switching-capability": "switching-psc1",
"encoding": "lsp-encoding-packet",
"max-lsp-bandwidth": [
{
"priority": 7,
"te-bandwidth": {
"generic": "0x1p22"
}
}
]
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}
]
}
},
{
"tp-id": "3-2-1",
"ietf-l3-unicast-topology:l3-termination-point-attributes": {
"unnumbered-id": 321
}
}
],
"ietf-l3-unicast-topology:l3-node-attributes": {
"router-id": ["203.0.113.3"],
"prefix": [
{
"prefix": "203.0.113.3/32",
"ietf-sr-mpls-topology:sr-mpls": {
"sids": {
"sid": [
{
"algorithm": "prefix-sid-algorithm-shortest-path",
"start-sid": 103,
"range": 1,
"is-local": false,
"is-node": true
}
]
}
}
}
],
"ietf-sr-mpls-topology:sr-mpls": {
"srgb": [
{
"lower-bound": 16000,
"upper-bound": 23999
}
],
"srlb": [
{
"lower-bound": 15000,
"upper-bound": 15999
}
]
}
},
"ietf-te-topology:te-node-id": "203.0.113.3",
"ietf-te-topology:te": {
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"te-node-attributes": {
"admin-status": "up",
"domain-id": 1001,
"signaling-address": [
"203.0.113.3"
]
}
}
}
],
"ietf-network-topology:link": [
{
"link-id": "D1,1-2-1,D2,2-1-1",
"source": {
"source-node": "D1",
"source-tp": "1-2-1"
},
"destination": {
"dest-node": "D2",
"dest-tp": "2-1-1"
},
"ietf-l3-unicast-topology:l3-link-attributes": {
"metric1": "100",
"ietf-sr-mpls-topology:sr-mpls": {
"sids": {
"sid": [
{
"value-type": "index",
"sid": 121,
"is-local": true
}
]
}
}
},
"ietf-te-topology:te": {
"te-link-attributes": {
"interface-switching-capability": [
{
"switching-capability": "switching-psc1",
"encoding": "lsp-encoding-packet",
"ietf-te-topology-packet:packet-switch-capable":
{
"minimum-lsp-bandwidth": "0x1p20"
}
}
]
}
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}
},
{
"link-id": "D2,2-1-1,D1,1-2-1",
"source": {
"source-node": "D2",
"source-tp": "2-1-1"
},
"destination": {
"dest-node": "D1",
"dest-tp": "1-2-1"
},
"ietf-l3-unicast-topology:l3-link-attributes": {
"metric1": "100",
"ietf-sr-mpls-topology:sr-mpls": {
"sids": {
"sid": [
{
"value-type": "index",
"sid": 211,
"is-local": true
}
]
}
}
},
"ietf-te-topology:te": {
"te-link-attributes": {
"interface-switching-capability": [
{
"switching-capability": "switching-psc1",
"encoding": "lsp-encoding-packet",
"ietf-te-topology-packet:packet-switch-capable":
{
"minimum-lsp-bandwidth": "0x1p20"
}
}
]
}
}
},
{
"link-id": "D1,1-3-1,D3,3-1-1",
"source": {
"source-node": "D1",
"source-tp": "1-3-1"
},
"destination": {
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"dest-node": "D3",
"dest-tp": "3-1-1"
},
"ietf-l3-unicast-topology:l3-link-attributes": {
"metric1": "100",
"ietf-sr-mpls-topology:sr-mpls": {
"sids": {
"sid": [
{
"value-type": "index",
"sid": 131,
"is-local": true
}
]
}
}
},
"ietf-te-topology:te": {
"te-link-attributes": {
"is-abstract": [null],
"underlay": {
"enabled": true,
"primary-path": {
"network-ref": "underlay-example",
"path-element": [
{
"path-element-id": 1,
"label-hop": {
"te-label": {
"generic": "MTcwNTE=",
"direction": "forward"
}
}
},
{
"path-element-id": 2,
"label-hop": {
"te-label": {
"generic": "MTcwNTI=",
"direction": "forward"
}
}
},
{
"path-element-id": 3,
"label-hop": {
"te-label": {
"generic": "MTcwNTM=",
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"direction": "forward"
}
}
}
]
}
},
"interface-switching-capability": [
{
"switching-capability": "switching-psc1",
"encoding": "lsp-encoding-packet",
"ietf-te-topology-packet:packet-switch-capable":
{
"minimum-lsp-bandwidth": "0x1p20"
}
}
]
}
}
},
{
"link-id": "D3,3-1-1,D1,1-3-1",
"source": {
"source-node": "D3",
"source-tp": "3-1-1"
},
"destination": {
"dest-node": "D1",
"dest-tp": "1-3-1"
},
"ietf-l3-unicast-topology:l3-link-attributes": {
"metric1": "100",
"ietf-sr-mpls-topology:sr-mpls": {
"sids": {
"sid": [
{
"value-type": "index",
"sid": 311,
"is-local": true
}
]
}
}
},
"ietf-te-topology:te": {
"te-link-attributes": {
"is-abstract": [null],
"interface-switching-capability": [
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{
"switching-capability": "switching-psc1",
"encoding": "lsp-encoding-packet",
"ietf-te-topology-packet:packet-switch-capable":
{
"minimum-lsp-bandwidth": "0x1p20"
}
}
]
}
}
},
{
"link-id": "D2,2-3-1,D3,3-2-1",
"source": {
"source-node": "D2",
"source-tp": "2-3-1"
},
"destination": {
"dest-node": "D3",
"dest-tp": "3-2-1"
},
"ietf-l3-unicast-topology:l3-link-attributes": {
"metric1": "100",
"ietf-sr-mpls-topology:sr-mpls": {
"sids": {
"sid": [
{
"value-type": "index",
"sid": 231,
"is-local": true
}
]
}
}
}
},
{
"link-id": "D3,3-2-1,D2,2-3-1",
"source": {
"source-node": "D3",
"source-tp": "3-2-1"
},
"destination": {
"dest-node": "D2",
"dest-tp": "2-3-1"
},
"ietf-l3-unicast-topology:l3-link-attributes": {
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"metric1": "100",
"ietf-sr-mpls-topology:sr-mpls": {
"sids": {
"sid": [
{
"value-type": "index",
"sid": 321,
"is-local": true
}
]
}
}
}
}
]
}
]
}
}
Appendix C. Contributors
Jeff Tantsura
Email: jefftant.ietf@gmail.com
Yingzhen Qu
Email: yingzhen.qu@huawei.com
Authors' Addresses
Xufeng Liu
IBM Corporation
EMail: xufeng.liu.ietf@gmail.com
Igor Bryskin
Individual
EMail: i_bryskin@yahoo.com
Vishnu Pavan Beeram
Juniper Networks
EMail: vbeeram@juniper.net
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Tarek Saad
Juniper Networks
EMail: tsaad@juniper.net
Himanshu Shah
Ciena
EMail: hshah@ciena.com
Stephane Litkowski
Cisco
EMail: slitkows.ietf@gmail.com
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