Network Working Group X. Liu
Internet-Draft Volta Networks
Intended status: Standards Track I. Bryskin
Expires: January 2, 2019 Huawei Technologies
V. Beeram
Juniper Networks
T. Saad
Cisco Systems Inc
H. Shah
Ciena
S. Litkowski
Orange Business Service
July 1, 2018
YANG Data Model for SR and SR TE Topologies
draft-ietf-teas-yang-sr-te-topo-02
Abstract
This document defines a YANG data model for Segment Routing (SR)
topology and Segment Routing (SR) traffic engineering (TE) topology.
Status of This Memo
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This Internet-Draft will expire on January 2, 2019.
Copyright Notice
Copyright (c) 2018 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
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 2
1.2. Tree Diagrams . . . . . . . . . . . . . . . . . . . . . . 3
2. Modeling Considerations . . . . . . . . . . . . . . . . . . . 3
2.1. Segment Routing (SR) Topology . . . . . . . . . . . . . . 3
2.2. Segment Routing (SR) TE Topology . . . . . . . . . . . . 3
2.3. Relations to ietf-segment-routing . . . . . . . . . . . . 4
2.4. Topology Type Modeling . . . . . . . . . . . . . . . . . 5
2.5. Topology Attributes . . . . . . . . . . . . . . . . . . . 5
2.6. Node Attributes . . . . . . . . . . . . . . . . . . . . . 5
2.7. Link Termination Point Attributes . . . . . . . . . . . . 6
2.8. Link in the Topology Model . . . . . . . . . . . . . . . 7
3. Model Structure . . . . . . . . . . . . . . . . . . . . . . . 7
4. YANG Module . . . . . . . . . . . . . . . . . . . . . . . . . 9
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15
6. Security Considerations . . . . . . . . . . . . . . . . . . . 15
7. References . . . . . . . . . . . . . . . . . . . . . . . . . 16
7.1. Normative References . . . . . . . . . . . . . . . . . . 16
7.2. Informative References . . . . . . . . . . . . . . . . . 16
Appendix A. Companion YANG Model for Non-NMDA Compliant
Implementations . . . . . . . . . . . . . . . . . . 18
A.1. SR Topology State Module . . . . . . . . . . . . . . . . 18
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 21
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.
1.1. Terminology
The keywords "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].
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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].
2. Modeling Considerations
2.1. Segment Routing (SR) Topology
The Layer 3 network topology model is discussed in [RFC8346]. The
Segment Routing (SR) topology model proposed in this document
augments and uses the ietf-l3-unicast-igp-topology module defined in
[RFC8346]. SR related attributes are covered in the ietf-sr-topology
model.
+------------------------------+
| Layer 3 Network Topology |
| ietf-l3-unicast-topology |
+------------------------------+
|
|
|
V
+------------------------+
| SR Topology |
| ietf-sr-topology |
+------------------------+
2.2. Segment Routing (SR) TE Topology
When traffic engineering is enabled on an SR topology, there will be
associations between objects in SR topologies and objects in TE
topologies. An SR TE topology is both an SR topology and a layer 3
TE topology. Multiple inheritance is used to achieve such relations.
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+------------------+ +---------------------+
| SR Topology | | L3 TE Topology |
| ietf-sr-topology | | ietf-l3-te-topology |
+------------------+ +---------------------+
\ /
\ /
\ /
v v
+------------------------+
| SR TE Topology |
| |
+------------------------+
Each type of topologies is indicated by "network-types" defined in
[RFC8345]. For the three types of topologies above, the data
representations are:
L3 Topology:
/nd:networks/nd:network/nd:network-types/l3-unicast-topology
L3 TE Topology:
/nd:networks/nd:network/nd:network-types/l3-unicast-topology/l3-te
SR Topology:
/nd:networks/nd:network/nd:network-types/l3-unicast-topology/sr
SR TE Topology: (multiple inheritance)
/nd:networks/nd:network/nd:network-types/l3-unicast-topology/l3-te
/nd:networks/nd:network/nd:network-types/l3-unicast-topology/sr
2.3. Relations to ietf-segment-routing
[I-D.ietf-spring-sr-yang] defines ietf-segment-routing that is a
model intended to be used on network elements to configure or operate
segment routing; ietf-sr-topology defined in this document is
intended to be used on a controller for the network-wide operations
such as path computation.
SR topology model shares many modeling constructs defined in ietf-
segment-routing. The module ietf-sr-topology uses the types and
groupings defined in ietf-segment-routing.
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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.
augment /nw:networks/nw:network/nw:network-types
/l3t:l3-unicast-topology:
+--rw sr!
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. 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
+--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.
The SR attributes that have node-scope impact are modeled by
augmenting the container "l3-node-attributes" in the L3 topology
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:
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augment /nw:networks/nw:network/nw:node/l3t:l3-node-attributes:
+--rw sr
+--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 node-capabilities
| +--rw transport-planes* [transport-plane]
| | +--rw transport-plane identityref
| +--rw readable-label-stack-depth? uint8
+--ro information-source? enumeration
+--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!
+--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
2.7. Link Termination Point Attributes
A link termination point in the topology model is mapped to an
interface from the Segment Routing perspective. The Adjacency
Segment attributes on an interface are modeled within a link
termination point. The modeling structure is as follows:
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augment /nw:networks/nw:network/nw:node/nt:termination-point
/l3t:l3-termination-point-attributes:
+--rw sr!
+--rw value-type? enumeration
+--rw sid uint32
+--rw advertise-protection? enumeration
+--rw is-local? boolean
+--ro is-backup? boolean
+--ro is-part-of-set? boolean
+--ro is-on-lan? boolean
+--ro information-source? enumeration
+--ro information-source-state
+--ro credibility-preference? uint16
The usage of the leaf "advertise-protection" is described in
[I-D.ietf-spring-sr-yang].
Since YANG models are usually implemented with persistent
configuration datastores, this model supports only persistent
Adjacency Segments.
Both IGP and BGP 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
[I-D.ietf-teas-yang-te-topo]
2.8. Link in the Topology Model
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.
3. Model Structure
The model tree structure of the Segment Routing (SR) topology module
is as shown below:
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module: ietf-sr-topology
augment /nw:networks/nw:network/nw:network-types
/l3t:l3-unicast-topology:
+--rw sr!
augment /nw:networks/nw:network/l3t:l3-topology-attributes:
+--rw sr
+--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
+--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 node-capabilities
| +--rw transport-planes* [transport-plane]
| | +--rw transport-plane identityref
| +--rw readable-label-stack-depth? uint8
+--ro information-source? enumeration
+--ro information-source-state
+--ro credibility-preference? uint16
augment /nw:networks/nw:network/nw:node/l3t:l3-node-attributes
/l3t:prefix:
+--rw sr!
+--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
augment /nw:networks/nw:network/nw:node/nt:termination-point
/l3t:l3-termination-point-attributes:
+--rw sr!
+--rw value-type? enumeration
+--rw sid uint32
+--rw advertise-protection? enumeration
+--rw is-local? boolean
+--ro is-backup? boolean
+--ro is-part-of-set? boolean
+--ro is-on-lan? boolean
+--ro information-source? enumeration
+--ro information-source-state
+--ro credibility-preference? uint16
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4. YANG Module
<CODE BEGINS> file "ietf-sr-topology@2018-06-22.yang"
module ietf-sr-topology {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-sr-topology";
prefix "srt";
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
"I-D.ietf-spring-sr-yang: 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
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<mailto:hshah@ciena.com>
Editor: Stephane Litkowski
<mailto:stephane.litkowski@orange.com>";
description
"YANG data model for representing and manipulating Segment
Routing Topologies.
Copyright (c) 2018 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 2018-06-22 {
description "Initial revision";
reference
"RFC XXXX: YANG Data Model for SR and SR TE Topologies";
}
grouping sr-topology-type {
description
"Identifies the SR topology type.";
container sr {
presence "Indiates SR Topology";
description
"Its presence identifies the SR topology type.";
}
}
augment "/nw:networks/nw:network/nw:network-types/"
+ "l3t:l3-unicast-topology" {
description
"Defines the SR topology type.";
uses sr-topology-type;
}
augment "/nw:networks/nw:network/l3t:l3-topology-attributes" {
when "../nw:network-types/l3t:l3-unicast-topology/srt:sr" {
description "Augment only for SR topology.";
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}
description "Augment topology configuration";
uses sr-topology-attributes;
}
augment "/nw:networks/nw:network/nw:node/l3t:l3-node-attributes" {
when "../../nw:network-types/l3t:l3-unicast-topology/srt:sr" {
description "Augment only for SR 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/srt:sr" {
description "Augment only for SR topology.";
}
description "Augment node prefix.";
uses sr-node-prefix-attributes;
}
augment "/nw:networks/nw:network/nw:node/nt:termination-point/"
+ "l3t:l3-termination-point-attributes" {
when "../../../nw:network-types/l3t:l3-unicast-topology/"
+ "srt:sr" {
description "Augment only for SR topology.";
}
description "Augment termination point configuration";
uses sr-tp-attributes;
}
grouping sr-topology-attributes {
description "SR topology scope attributes.";
container sr {
description
"Containing SR attributes.";
uses sr-cmn:srgb-cfg;
} // sr
} // sr-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" {
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description "The source is unknown.";
}
enum "locally-configured" {
description "Configured entity.";
}
enum "ospfv2" {
description "OSPFv2.";
}
enum "ospfv3" {
description "OSPFv3.";
}
enum "isis" {
description "ISIS.";
}
enum "system-processed" {
description "System processed entity.";
}
enum "other" {
description "Other source.";
}
}
config false;
description
"Indicates the source of the information.";
}
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 {
description
"Containing SR attributes.";
uses sr-cmn:srgb-cfg;
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uses sr-cmn:srlb-cfg;
uses sr-cmn:node-capabilities;
// 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 {
presence "Presence indicates SR is enabled.";
description
"Containing SR attributes for a prefix.";
uses sr-cmn:prefix-sid-attributes;
uses sr-cmn:last-hop-behavior;
leaf is-local {
type boolean;
description
"'true' if the SID is local.";
}
} // sr
} // sr-node-prefix-attributes
grouping sr-tp-attributes {
description "SR termination point scope attributes";
container sr {
presence "Presence indicates SR is enabled.";
description
"Containing SR attributes.";
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 advertise-protection {
type enumeration {
enum "single" {
description
"A single Adj-SID is associated
with the adjacency and reflects
the protection configuration.";
}
enum "dual" {
description
"Two Adj-SIDs will be associated
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with the adjacency if interface
is protected. In this case
one will be enforced with
backup flag set, the other
will be enforced to backup flag unset.
In case, protection is not configured,
a single Adj-SID will be advertised
with backup flag unset.";
}
}
description
"If set, the Adj-SID refers to an
adjacency being protected.";
}
leaf is-local {
type boolean;
description
"'true' if the SID is local.";
}
leaf is-backup {
type boolean;
config false;
description
"'true' if the SID is a backup.";
}
leaf is-part-of-set {
type boolean;
config false;
description
"'true' if the SID is part of a set.";
}
leaf is-on-lan {
type boolean;
config false;
description
"'true' if on a lan.";
}
uses information-source-attributes;
} // sr
} // sr-tp-attributes
}
<CODE ENDS>
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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]:
--------------------------------------------------------------------
URI: urn:ietf:params:xml:ns:yang:ietf-sr-topology
Registrant Contact: The IESG.
XML: N/A, the requested URI is an XML namespace.
--------------------------------------------------------------------
--------------------------------------------------------------------
URI: urn:ietf:params:xml:ns:yang:ietf-sr-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-topology
namespace: urn:ietf:params:xml:ns:yang:ietf-sr-topology
prefix: srt
reference: RFC XXXX
--------------------------------------------------------------------
--------------------------------------------------------------------
name: ietf-sr-topology-state
namespace: urn:ietf:params:xml:ns:yang:ietf-sr-topology-state
prefix: srt-s
reference: RFC XXXX
--------------------------------------------------------------------
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 data-model by itself does not create any security
implications. The security considerations for the NETCONF protocol
are applicable. The NETCONF protocol used for sending the data
supports authentication and encryption.
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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>.
[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>.
[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>.
[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>.
7.2. Informative References
[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>.
[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>.
[I-D.ietf-teas-yang-te-topo]
Liu, X., Bryskin, I., Beeram, V., Saad, T., Shah, H., and
O. Dios, "YANG Data Model for Traffic Engineering (TE)
Topologies", draft-ietf-teas-yang-te-topo-18 (work in
progress), June 2018.
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[I-D.ietf-spring-sr-yang]
Litkowski, S., Qu, Y., Sarkar, P., and J. Tantsura, "YANG
Data Model for Segment Routing", draft-ietf-spring-sr-
yang-08 (work in progress), December 2017.
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Appendix A. Companion YANG Model for Non-NMDA Compliant Implementations
The YANG module ietf-sr-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-topology-state, is defined as state model, which mirrors the
module ietf-sr-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-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 Topology State Module
<CODE BEGINS> file "ietf-sr-topology-state@2018-06-22.yang"
module ietf-sr-topology-state {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-sr-topology-state";
prefix "srt-s";
import ietf-sr-topology {
prefix "srt";
}
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 {
prefix "sr-cmn";
reference
"I-D.ietf-spring-sr-yang: 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 operational state information
of Segment Routing Topologies, when NMDA is not supported.
Copyright (c) 2018 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 2018-06-22 {
description "Initial revision";
reference
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"RFC XXXX: YANG Data Model for SR and SR TE Topologies";
}
augment "/nw-s:networks/nw-s:network/nw-s:network-types/"
+ "l3t-s:l3-unicast-topology" {
description
"Defines the SR topology type.";
uses srt:sr-topology-type;
}
augment "/nw-s:networks/nw-s:network/"
+ "l3t-s:l3-topology-attributes" {
when "../nw-s:network-types/l3t-s:l3-unicast-topology/srt-s:sr" {
description "Augment only for SR topology.";
}
description "Augment topology configuration";
uses srt:sr-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/"
+ "srt-s:sr" {
description "Augment only for SR topology.";
}
description "Augment node configuration.";
uses srt: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/"
+ "srt-s:sr" {
description "Augment only for SR topology.";
}
description "Augment node prefix.";
uses srt:sr-node-prefix-attributes;
}
augment "/nw-s:networks/nw-s:network/nw-s:node/"
+ "nt-s:termination-point/"
+ "l3t-s:l3-termination-point-attributes" {
when "../../../nw-s:network-types/l3t-s:l3-unicast-topology/"
+ "srt-s:sr" {
description "Augment only for SR topology.";
}
description "Augment termination point configuration";
uses srt:sr-tp-attributes;
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}
grouping sr-topology-attributes {
description "SR topology scope attributes.";
container sr {
description
"Containing SR attributes.";
uses sr-cmn:srgb-cfg;
} // sr
} // sr-topology-attributes
}
<CODE ENDS>
Authors' Addresses
Xufeng Liu
Volta Networks
EMail: xufeng.liu.ietf@gmail.com
Igor Bryskin
Huawei Technologies
EMail: Igor.Bryskin@huawei.com
Vishnu Pavan Beeram
Juniper Networks
EMail: vbeeram@juniper.net
Tarek Saad
Cisco Systems Inc
EMail: tsaad@cisco.com
Himanshu Shah
Ciena
EMail: hshah@ciena.com
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Stephane Litkowski
Orange Business Service
EMail: stephane.litkowski@orange.com
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