YANG Data Model for Topology Filter
draft-ietf-teas-yang-topology-filter-03
| Document | Type | Active Internet-Draft (teas WG) | |
|---|---|---|---|
| Authors | Vishnu Pavan Beeram , Tarek Saad , Rakesh Gandhi , Xufeng Liu | ||
| Last updated | 2026-07-05 | ||
| Replaces | draft-bestbar-teas-yang-topology-filter | ||
| RFC stream | Internet Engineering Task Force (IETF) | ||
| Intended RFC status | (None) | ||
| Formats | |||
| Yang Validation | 0 errors, 0 warnings | ||
| Reviews |
YANGDOCTORS Early review
(of
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by Reshad Rahman
On the right track
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||
| Additional resources | Mailing list discussion | ||
| Stream | WG state | WG Document | |
| Document shepherd | (None) | ||
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| Send notices to | (None) |
draft-ietf-teas-yang-topology-filter-03
TEAS V. P. Beeram
Internet-Draft HPE
Intended status: Standards Track T. Saad
Expires: 6 January 2027 R. Gandhi
Cisco Systems
X. Liu
Individual
5 July 2026
YANG Data Model for Topology Filter
draft-ietf-teas-yang-topology-filter-03
Abstract
This document defines a YANG data model for the management of
topology filters/filter-sets on network elements and controllers.
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 6 January 2027.
Copyright Notice
Copyright (c) 2026 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents (https://trustee.ietf.org/
license-info) in effect on the date of publication of this document.
Please review these documents carefully, as they describe your rights
and restrictions with respect to this document. Code Components
extracted from this document must include Revised BSD License text as
described in Section 4.e of the Trust Legal Provisions and are
provided without warranty as described in the Revised BSD License.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Requirements Language . . . . . . . . . . . . . . . . . . 3
1.2. Use-Cases . . . . . . . . . . . . . . . . . . . . . . . . 3
1.3. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3
1.4. Tree Structure . . . . . . . . . . . . . . . . . . . . . 4
2. Topology Filter Data Model . . . . . . . . . . . . . . . . . 4
2.1. Model Structure . . . . . . . . . . . . . . . . . . . . . 4
2.1.1. Topology Filters . . . . . . . . . . . . . . . . . . 4
2.1.2. Topology Filter-Sets . . . . . . . . . . . . . . . . 7
2.2. YANG Module . . . . . . . . . . . . . . . . . . . . . . . 7
3. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 14
4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15
5. Security Considerations . . . . . . . . . . . . . . . . . . . 15
6. References . . . . . . . . . . . . . . . . . . . . . . . . . 16
6.1. Normative References . . . . . . . . . . . . . . . . . . 16
6.2. Informative References . . . . . . . . . . . . . . . . . 17
Appendix A. Usage Examples . . . . . . . . . . . . . . . . . . . 18
A.1. Example 1: ISIS Level-2 Filter with Include-Any . . . . . 18
A.2. Example 2: ISIS Flex-Algo Filter with Exclude . . . . . . 19
A.3. Example 3: NRP Filter with Include-All and Exclude . . . 20
Complete Model Tree Structure . . . . . . . . . . . . . . . . . . 21
Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 23
1. Introduction
A topology filter is a data construct that is used to filter network
topologies [RFC8345]. It can be applied on either a native topology
or a customized topology [RFC8795] to produce a filtered set of
topological elements. A topology filter-set is a union of multiple
topology filters that can be applied in tandem on a topology. This
document defines a YANG data model for the management of topology
filters/filter-sets on network elements and controllers.
The authors acknowledge that an implementation may maintain network
topologies that are learnt via routing protocols in a Routing
Information Base (RIB) [RFC8431] and use routing policies [RFC9067]
to filter the entries in the RIB. Such an implementation is not the
target of this document.
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1.1. Requirements Language
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.
1.2. Use-Cases
* Specification of topology related constraints for TE Path
Computation: A few examples of this are -
- Compute a path within a specified topology.
- Compute a path within the topology associated with a specific
IGP domain.
- Compute a path within the topology learnt from a specific TE
Information Source.
- Compute a path within the topology defined by the application
of one or more topology filters:
o Use a topology with elements learnt via ISIS Level-2 and
include resource-affinity "RED"
o Use a topology with elements associated with ISIS Flexible
Algorithm 128 and exclude resource-affinity "BLUE"
* Specification of topology associated with a Network Resource
Partition (NRP): A few examples of rules for determining the
topology associated with the NRP [RFC9543] are:
- All the elements in the specified topology are part of the NRP
topology.
- All the topological elements associated with a specific IGP
domain are part of the NRP topology.
- All the topological elements that include resource-affinity
"RED" and exclude resource-affinity "BLUE" are part of the NRP
topology.
1.3. Terminology
The terminology for describing YANG data models is found in
[RFC7950].
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The reader is expected to be familiar with the topology modeling
terminology specified in [RFC8345], [RFC8776] and [RFC8795].
1.4. Tree Structure
A simplified graphical representation of the data model is presented
in the appendix of this document. The tree format defined in
[RFC8340] is used for the YANG data model tree representation.
2. Topology Filter Data Model
2.1. Model Structure
The high-level model structure defined by this document is as shown
below:
module: ietf-topology-filter
augment /nw:networks:
+--rw topology-filters!
| +--rw topology-filter* [name]
| +--rw name string
| +--rw topology-ref
| | ..........
| +--rw include-any
| | ..........
| +--rw include-all
| | ..........
| +--rw exclude
| ..........
+--rw topology-filter-sets!
+--rw topology-filter-set* [name]
+--rw name string
+ ..........
The top-level 'networks' container [RFC8345] is augmented with a set
of topology filters and a set of topology filter-sets.
2.1.1. Topology Filters
The 'topology-filters' container carries a list of topology filters.
Each topology-filter entry specifies a set of include-any, include-
all and exclude filtering rules that can be applied on either the
native topology or a user specified topology.
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2.1.1.1. Topology Reference
The 'topology-reference' container indicates the topology on which
the filtering rules need to be applied. The referenced topology
could be a predefined TE topology and/or a specific IGP domain. The
absence of the 'topology-reference' indicates that the filtering
rules are to be applied on the native topology.
The 'igp-domain-identifier' container identifies a specific IGP
domain using the following attributes:
* 'protocol-id': The IGP protocol type (e.g., OSPFv2, OSPFv3, IS-
IS).
* 'instance-id': The identifier of the IGP protocol instance.
Multiple instances of the same IGP protocol can coexist on a
network element.
* 'division-id': The identifier of a division within the IGP
instance. The semantics of this field depend on the IGP protocol
type: for OSPF, this is the Area ID; for IS-IS, this is the Level.
* 'algo-number': The algorithm number associated with the topology
(e.g., the IGP Flexible Algorithm number).
* 'mt-id': The Multi-Topology Identifier as defined in [RFC4915] for
OSPF and [RFC5120] for IS-IS.
When any of these leaves are absent from the 'igp-domain-identifier'
container, they are treated as wildcards and match any value.
Similarly, when any of the leaves in the 'te-topology-identifier'
container are absent, they are treated as wildcards and match any
value.
+--rw topology-ref
+--rw igp-domain-identifier
| +--rw protocol-id? igp-protocol
| +--rw instance-id? uint32
| +--rw division-id? uint32
| +--rw algo-number? uint8
| +--rw mt-id? uint16
+--rw te-topology-identifier
+--rw provider-id? te-global-id
+--rw client-id? te-global-id
+--rw topology-id? te-topology-id
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2.1.1.2. Filters
The 'include-any', 'include-all' and 'exclude' containers carry a
varied set of attributes that can be used as rules to filter the
topology. If the topology-filter entry carries no filtering rules
and only references a specific topology, then the set of filtered
topological elements produced is the same as the one defined by the
referenced topology. When a filter attribute (leaf-list or list) is
absent or empty in a given container, it is treated as a wildcard and
does not constrain the filter results for that attribute type.
The filtering semantics are as follows:
* 'include-any': A topological element matches the 'include-any'
container if, for each populated attribute list, it matches at
least one attribute in that list (OR within each attribute list,
AND across attribute lists).
* 'include-all': A topological element matches the 'include-all'
container if, for each populated attribute list, it matches all
attributes in that list (AND within each attribute list, AND
across attribute lists).
* 'exclude': A topological element matches the 'exclude' container
if, for each populated attribute list, it matches at least one
attribute in that list (OR within each attribute list, AND across
attribute lists).
A topological element is included in the resulting filtered topology
if and only if it satisfies all of the following conditions (AND
operation across containers):
1. It matches the 'include-any' container (if populated).
2. It matches the 'include-all' container (if populated).
3. It does not match the 'exclude' container (if populated).
If an OR operation across attribute lists is desired for 'include-
any', this can be achieved by defining multiple topology filters
(each with its own 'include-any' container) and combining them using
a topology-filter-set, which produces a union of the individual
filter results.
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+--rw include-any
| +--rw link-affinity* string
| +--rw link-name* string
| +--rw node-prefix* inet:ip-prefix
| +--rw as* inet:as-number
| +--rw info-source* [source-id instance-id division-id]
| +--rw source-id tet:te-info-source
| +--rw instance-id uint32
| +--rw division-id uint32
+--rw include-all
| +--rw link-affinity* string
| +--rw link-name* string
| +--rw node-prefix* inet:ip-prefix
| +--rw as* inet:as-number
| +--rw info-source* [source-id instance-id division-id]
| +--rw source-id tet:te-info-source
| +--rw instance-id uint32
| +--rw division-id uint32
+--rw exclude
+--rw link-affinity* string
+--rw link-name* string
+--rw node-prefix* inet:ip-prefix
+--rw as* inet:as-number
+--rw info-source* [source-id instance-id division-id]
+--rw source-id tet:te-info-source
+--rw instance-id uint32
+--rw division-id uint32
2.1.2. Topology Filter-Sets
The 'topology-filter-sets' container carries a list of topology
filter-sets. Each topology-filter-set entry constitutes a list of
topology-filter references. This is used when there is a need to
create a union of multiple topology filters.
+--rw topology-filter-sets!
+--rw topology-filter-set* [name]
+--rw name string
+--rw topology-filter*
-> ../../../topology-filters/topology-filter/name
2.2. YANG Module
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<CODE BEGINS> file "ietf-topology-filter@2025-10-19.yang"
module ietf-topology-filter {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-topology-filter";
prefix topo-filt;
import ietf-inet-types {
prefix inet;
reference
"RFC 6991: Common YANG Data Types";
}
import ietf-network {
prefix nw;
reference
"RFC 8345: A YANG Data Model for Network Topologies";
}
import ietf-te-types {
prefix te-types;
reference
"RFC 8776: Common YANG Data Types for Traffic Engineering";
}
import ietf-te-topology {
prefix tet;
reference
"RFC 8795: YANG Data Model for Traffic Engineering Topologies";
}
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: Vishnu Pavan Beeram
<mailto:vishnupavan.ietf@gmail.com>
Editor: Tarek Saad
<mailto:tsaad.net@gmail.com>
Editor: Rakesh Gandhi
<mailto:rgandhi@cisco.com>
Editor: Xufeng Liu
<mailto:xufeng.liu.ietf@gmail.com>";
description
"This YANG module defines data definitions for managing
topology filters.
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Copyright (c) 2025 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 Revised BSD License set
forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
(https://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX; see the
RFC itself for full legal notices.";
revision 2025-10-19 {
description
"Initial revision.";
reference
"RFC XXXX: YANG Data Model for Topology Filters.";
}
/*
* T Y P E D E F S
*/
typedef igp-protocol {
type enumeration {
enum ospfv2 {
description
"OSPFv2.";
}
enum ospfv3 {
description
"OSPFv3.";
}
enum isis {
description
"IS-IS.";
}
}
description
"IGP Protocol Type.";
}
/*
* G R O U P I N G S
*/
/*
* Grouping - Topology Information Source.
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*/
grouping igp-topology-info-source {
description
"Grouping for igp topology information source.";
leaf protocol-id {
type igp-protocol;
description
"IGP Protocol Type.";
}
leaf instance-id {
type uint32;
description
"The identifier of the IGP protocol
instance.";
}
leaf division-id {
type uint32;
description
"The identifier of a division within the IGP
instance. The semantics of this field depend
on the IGP protocol type: for OSPF, this is
the Area ID; for IS-IS, this is the Level.";
}
}
/*
* Grouping - IGP Domain Identifier.
*/
grouping igp-domain-identifier {
description
"Grouping for igp domain identifier.";
container igp-domain-identifier {
description
"Container for igp domain identifier.";
uses igp-topology-info-source;
leaf algo-number {
type uint8;
description
"The algorithm number associated with
the topology (e.g., the IGP Flexible
Algorithm number).";
}
leaf mt-id {
type uint16;
description
"The Multi-Topology Identifier.";
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reference
"RFC 4915: Multi-Topology (MT) Routing
in OSPF
RFC 5120: M-ISIS: Multi Topology (MT)
Routing in Intermediate System to
Intermediate Systems (IS-ISs)";
}
}
}
/*
* Grouping - Topology Reference
*/
grouping topology-reference {
description
"Grouping for topology reference.";
container topology-ref {
description
"Container for topology reference.";
uses igp-domain-identifier;
uses te-types:te-topology-identifier;
}
}
/*
* Grouping - Topology Information Sources
*/
grouping topology-info-sources {
description
"Grouping for topology information sources.";
list info-source {
key "source-id instance-id division-id";
description
"List of information-sources.";
leaf source-id {
type tet:te-info-source;
description
"Information Source.";
}
leaf instance-id {
type uint32;
description
"The identifier of the information source
routing protocol instance.";
}
leaf division-id {
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type uint32;
description
"The identifier of a division within the
information source instance. For OSPF,
this is the Area ID; for IS-IS, this is
the Level.";
}
}
}
/*
* Grouping - Custom Topology Filters
*/
grouping custom-topology-filters {
description
"Grouping for custom topology filters.";
leaf-list link-affinity {
type string;
description
"List of link affinities.";
}
leaf-list link-name {
type string;
description
"List of link names.";
}
leaf-list node-prefix {
type inet:ip-prefix;
description
"List of node IDs.";
}
leaf-list as {
type inet:as-number;
description
"List of AS numbers.";
}
uses topology-info-sources;
}
/*
* Grouping - Topology Filters
*/
grouping topology-filters {
description
"Grouping for topology filters.";
container topology-filters {
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presence "Enable Topology Filters.";
description
"Container for topology filters.";
list topology-filter {
key "name";
description
"List of topology filters.";
leaf name {
type string;
description
"A string that uniquely identifies the topology filter.";
}
uses topology-reference;
container include-any {
description
"A topological element matches this container
if, for each populated attribute list, it
matches at least one attribute in that list
(OR within each list, AND across lists).";
uses custom-topology-filters;
}
container include-all {
description
"A topological element matches this container
if, for each populated attribute list, it
matches all attributes in that list
(AND within each list, AND across lists).";
uses custom-topology-filters;
}
container exclude {
description
"A topological element matches this container
if, for each populated attribute list, it
matches at least one attribute in that list
(OR within each list, AND across lists).
Matched elements are excluded from the
filtered topology.";
uses custom-topology-filters;
}
}
}
}
/*
* Grouping - Topology Filter Sets
*/
grouping topology-filter-sets {
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description
"Grouping for topology filter sets.";
container topology-filter-sets {
presence "Enable Topology Filter-Sets.";
description
"Container for topology filter sets.";
list topology-filter-set {
key "name";
description
"List of topology filter sets.";
leaf name {
type string;
description
"A string that uniquely identifies the topology
filter-set.";
}
leaf-list topology-filter {
type leafref {
path "../../../topo-filt:topology-filters/"
+ "topo-filt:topology-filter/topo-filt:name";
}
description
"Reference to a specific topology filter from the list
of topology filters.";
}
}
}
}
/*
* Augment - Topology Filters / Topology Filter-Sets
*/
augment "/nw:networks" {
description
"Augment networks with topology-filters and
topology-filter-sets.";
uses topology-filters;
uses topology-filter-sets;
}
}
<CODE ENDS>
3. Acknowledgements
The authors would like to thank Sudharsana Venkatraman for her input
from discussions.
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4. IANA Considerations
This document registers the following URI in the IETF XML registry
[RFC3688]. Following the format in [RFC3688], the following
registration is requested to be made.
URI: urn:ietf:params:xml:ns:yang:ietf-topology-filter
Registrant Contact: The TEAS WG of the IETF.
XML: N/A, the requested URI is an XML namespace.
This document registers a YANG module in the YANG Module Names
registry [RFC6020].
name: ietf-topology-filter
namespace: urn:ietf:params:xml:ns:yang:ietf-topology-filter
prefix: topo-filt
reference: RFCXXXX
5. Security Considerations
This section is modeled after the template described in Section 3.7.1
of [RFC9907].
The "ietf-topology-filter" YANG module defines a data model that is
designed to be accessed via YANG-based management protocols, such as
the Network Configuration Protocol (NETCONF) [RFC6241] and RESTCONF
[RFC8040]. These YANG-based management protocols (1) have to use a
secure transport layer (e.g., Secure Shell (SSH) [RFC4252], TLS
[RFC8446], and QUIC [RFC9000]) and (2) have to use mutual
authentication.
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). All writable data nodes are likely to be sensitive or
vulnerable in some network environments. Write operations (e.g.,
edit-config) and delete operations to these data nodes without proper
protection or authentication can have a negative effect on network
operations. The following subtrees and data nodes have particular
sensitivities/vulnerabilities:
* "/networks/topology-filters/": This subtree specifies the
configurations for topology filters. By manipulating these data
nodes, a malicious attacker may cause unauthorized and improper
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behavior to any service that is making use of the filtered set of
topological elements produced by the application of the
compromised topology filter.
* "/networks/topology-filter-sets": This subtree specifies the
configurations for topology filter-sets. By manipulating these
data nodes, a malicious attacker may cause unauthorized and
improper behavior to any service that is making use of the
filtered set of topological elements produced by the application
of the compromised topology filter-set.
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:
* "/networks/topology-filters": Unauthorized access to this subtree
can disclose the topology filters used in the network.
* "/networks/topology-filter-sets": Unauthorized access to this
subtree can disclose the topology filter-sets used in the network.
6. References
6.1. 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/rfc/rfc2119>.
[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
DOI 10.17487/RFC3688, January 2004,
<https://www.rfc-editor.org/rfc/rfc3688>.
[RFC4915] Psenak, P., Mirtorabi, S., Roy, A., Nguyen, L., and P.
Pillay-Esnault, "Multi-Topology (MT) Routing in OSPF",
RFC 4915, DOI 10.17487/RFC4915, June 2007,
<https://www.rfc-editor.org/rfc/rfc4915>.
[RFC5120] Przygienda, T., Shen, N., and N. Sheth, "M-ISIS: Multi
Topology (MT) Routing in Intermediate System to
Intermediate Systems (IS-ISs)", RFC 5120,
DOI 10.17487/RFC5120, February 2008,
<https://www.rfc-editor.org/rfc/rfc5120>.
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[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/rfc/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/rfc/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/rfc/rfc7950>.
[RFC8040] Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017,
<https://www.rfc-editor.org/rfc/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/rfc/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/rfc/rfc8341>.
[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/rfc/rfc8345>.
[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/rfc/rfc8446>.
[RFC8776] Saad, T., Gandhi, R., Liu, X., Beeram, V., and I. Bryskin,
"Common YANG Data Types for Traffic Engineering",
RFC 8776, DOI 10.17487/RFC8776, June 2020,
<https://www.rfc-editor.org/rfc/rfc8776>.
[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/rfc/rfc8795>.
6.2. Informative References
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[RFC4252] Ylonen, T. and C. Lonvick, Ed., "The Secure Shell (SSH)
Authentication Protocol", RFC 4252, DOI 10.17487/RFC4252,
January 2006, <https://www.rfc-editor.org/rfc/rfc4252>.
[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/rfc/rfc8340>.
[RFC8431] Wang, L., Chen, M., Dass, A., Ananthakrishnan, H., Kini,
S., and N. Bahadur, "A YANG Data Model for the Routing
Information Base (RIB)", RFC 8431, DOI 10.17487/RFC8431,
September 2018, <https://www.rfc-editor.org/rfc/rfc8431>.
[RFC9000] Iyengar, J., Ed. and M. Thomson, Ed., "QUIC: A UDP-Based
Multiplexed and Secure Transport", RFC 9000,
DOI 10.17487/RFC9000, May 2021,
<https://www.rfc-editor.org/rfc/rfc9000>.
[RFC9067] Qu, Y., Tantsura, J., Lindem, A., and X. Liu, "A YANG Data
Model for Routing Policy", RFC 9067, DOI 10.17487/RFC9067,
October 2021, <https://www.rfc-editor.org/rfc/rfc9067>.
[RFC9543] Farrel, A., Ed., Drake, J., Ed., Rokui, R., Homma, S.,
Makhijani, K., Contreras, L., and J. Tantsura, "A
Framework for Network Slices in Networks Built from IETF
Technologies", RFC 9543, DOI 10.17487/RFC9543, March 2024,
<https://www.rfc-editor.org/rfc/rfc9543>.
[RFC9907] Bierman, A., Boucadair, M., Ed., and Q. Wu, "Guidelines
for Authors and Reviewers of Documents Containing YANG
Data Models", BCP 216, RFC 9907, DOI 10.17487/RFC9907,
March 2026, <https://www.rfc-editor.org/rfc/rfc9907>.
Appendix A. Usage Examples
This appendix provides JSON encoding examples of the topology filter
configuration as defined in this document. The examples use JSON
encoding per [RFC7950] and [RFC8040].
A.1. Example 1: ISIS Level-2 Filter with Include-Any
This example creates a topology filter named "isis-level2-red" that
operates on the IS-IS Level-2 topology and includes topological
elements that have link-affinity "RED". Since only one attribute
list is populated in 'include-any', an element is included if it
matches at least one value in that list. This corresponds to the
use-case: "Use a topology with elements learnt via ISIS Level-2 and
include resource-affinity RED".
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{
"ietf-network:networks": {
"ietf-topology-filter:topology-filters": {
"topology-filter": [
{
"name": "isis-level2-red",
"topology-ref": {
"igp-domain-identifier": {
"protocol-id": "isis",
"division-id": 2
}
},
"include-any": {
"link-affinity": [
"RED"
]
}
}
]
}
}
}
A.2. Example 2: ISIS Flex-Algo Filter with Exclude
This example creates a topology filter named "isis-flexalgo128-no-
blue" that operates on the IS-IS topology associated with Flexible
Algorithm 128 and excludes topological elements with link-affinity
"BLUE". This corresponds to the use-case: "Use a topology with
elements associated with ISIS Flexible Algorithm 128 and exclude
resource-affinity BLUE".
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{
"ietf-network:networks": {
"ietf-topology-filter:topology-filters": {
"topology-filter": [
{
"name": "isis-flexalgo128-no-blue",
"topology-ref": {
"igp-domain-identifier": {
"protocol-id": "isis",
"algo-number": 128
}
},
"exclude": {
"link-affinity": [
"BLUE"
]
}
}
]
}
}
}
A.3. Example 3: NRP Filter with Include-All and Exclude
This example creates a topology filter named "nrp-filter" for
defining a Network Resource Partition (NRP) topology. It uses
'include-all' to require that topological elements match all values
in each populated attribute list (AND within each list) and satisfy
all populated attribute lists (AND across lists). In this case,
elements must have link-affinity "RED" AND belong to AS 65001. It
also excludes any element with link-affinity "BLUE". Additionally, a
topology-filter-set named "nrp-filter-set" is created that references
both "isis-level2-red" (from Example 1) and "nrp-filter" to form a
union of the two filters.
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{
"ietf-network:networks": {
"ietf-topology-filter:topology-filters": {
"topology-filter": [
{
"name": "nrp-filter",
"include-all": {
"link-affinity": [
"RED"
],
"as": [
65001
]
},
"exclude": {
"link-affinity": [
"BLUE"
]
}
}
]
},
"ietf-topology-filter:topology-filter-sets": {
"topology-filter-set": [
{
"name": "nrp-filter-set",
"topology-filter": [
"isis-level2-red",
"nrp-filter"
]
}
]
}
}
}
Complete Model Tree Structure
module: ietf-topology-filter
augment /nw:networks:
+--rw topology-filters!
| +--rw topology-filter* [name]
| +--rw name string
| +--rw topology-ref
| | +--rw igp-domain-identifier
| | | +--rw protocol-id? igp-protocol
| | | +--rw instance-id? uint32
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| | | +--rw division-id? uint32
| | | +--rw algo-number? uint8
| | | +--rw mt-id? uint16
| | +--rw te-topology-identifier
| | +--rw provider-id? te-global-id
| | +--rw client-id? te-global-id
| | +--rw topology-id? te-topology-id
| +--rw include-any
| | +--rw link-affinity* string
| | +--rw link-name* string
| | +--rw node-prefix* inet:ip-prefix
| | +--rw as* inet:as-number
| | +--rw info-source* [source-id instance-id division-id]
| | +--rw source-id tet:te-info-source
| | +--rw instance-id uint32
| | +--rw division-id uint32
| +--rw include-all
| | +--rw link-affinity* string
| | +--rw link-name* string
| | +--rw node-prefix* inet:ip-prefix
| | +--rw as* inet:as-number
| | +--rw info-source* [source-id instance-id division-id]
| | +--rw source-id tet:te-info-source
| | +--rw instance-id uint32
| | +--rw division-id uint32
| +--rw exclude
| +--rw link-affinity* string
| +--rw link-name* string
| +--rw node-prefix* inet:ip-prefix
| +--rw as* inet:as-number
| +--rw info-source* [source-id instance-id division-id]
| +--rw source-id tet:te-info-source
| +--rw instance-id uint32
| +--rw division-id uint32
+--rw topology-filter-sets!
+--rw topology-filter-set* [name]
+--rw name string
+--rw topology-filter*
-> ../../../topology-filters/topology-filter/name
Contributors
Colby Barth
HPE
Email: jonathan.barth@hpe.com
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Srihari R. Sangli
HPE
Email: srihari.sangli@hpe.com
Chandrasekar Ramachandran
HPE
Email: chandrasekar.ramachandran@hpe.com
Authors' Addresses
Vishnu Pavan Beeram
HPE
Email: vishnupavan.ietf@gmail.com
Tarek Saad
Cisco Systems
Email: tsaad.net@gmail.com
Rakesh Gandhi
Cisco Systems
Email: rgandhi@cisco.com
Xufeng Liu
Individual
Email: xufeng.liu.ietf@gmail.com
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