Support of Versioning in YANG Notifications Subscription
draft-ietf-netconf-yang-notifications-versioning-14
| Document | Type | Active Internet-Draft (netconf WG) | |
|---|---|---|---|
| Authors | Thomas Graf , Benoît Claise , Alex Huang Feng | ||
| Last updated | 2026-07-03 (Latest revision 2026-07-02) | ||
| Replaces | draft-tgraf-netconf-yang-notifications-versioning | ||
| RFC stream | Internet Engineering Task Force (IETF) | ||
| Intended RFC status | Proposed Standard | ||
| Formats | |||
| Yang Validation | 0 errors, 0 warnings | ||
| Reviews |
YANGDOCTORS Early review
(of
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by Robert Wills
Ready w/nits
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||
| Additional resources | Mailing list discussion | ||
| Stream | WG state | Submitted to IESG for Publication | |
| Document shepherd | Mohit P. Tahiliani | ||
| Shepherd write-up | Show Last changed 2026-07-02 | ||
| IESG | IESG state | Publication Requested | |
| Action Holder | |||
| Consensus boilerplate | Yes | ||
| Telechat date | (None) | ||
| Responsible AD | Mahesh Jethanandani | ||
| Send notices to | tahiliani.ietf@gmail.com |
draft-ietf-netconf-yang-notifications-versioning-14
Network Working Group T. Graf
Internet-Draft Swisscom
Intended status: Standards Track B. Claise
Expires: 4 January 2027 Huawei
A. Huang-Feng
Deutsche Telekom
3 July 2026
Support of Versioning in YANG Notifications Subscription
draft-ietf-netconf-yang-notifications-versioning-14
Abstract
This document defines a YANG module which extends the YANG-Push
Subscription mechanism to enforce that particular revisions or
semantic versions are used when configuring or establishing a
Subscription. It also extends the YANG-Push Subscription state
change Notifications to include additional context about the YANG
schema associated with the Subscription.
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 4 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
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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.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 4
2. Subscription Policy Extension . . . . . . . . . . . . . . . . 4
3. Subscription State Change Notification Extension . . . . . . 8
4. Discovering "ietf-yang-push-revision" Support . . . . . . . . 10
5. The "ietf-yang-push-revision" Module . . . . . . . . . . . . 11
5.1. Data Model Overview . . . . . . . . . . . . . . . . . . . 12
5.2. YANG Module . . . . . . . . . . . . . . . . . . . . . . . 22
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 28
6.1. IETF XML Registry . . . . . . . . . . . . . . . . . . . . 28
6.2. YANG Module Name . . . . . . . . . . . . . . . . . . . . 28
7. Operational Considerations . . . . . . . . . . . . . . . . . 29
8. Implementation Status . . . . . . . . . . . . . . . . . . . . 30
8.1. Huawei VRP . . . . . . . . . . . . . . . . . . . . . . . 30
8.2. 6WIND VSR . . . . . . . . . . . . . . . . . . . . . . . . 30
8.3. Cisco IOS XR . . . . . . . . . . . . . . . . . . . . . . 30
9. Security Considerations . . . . . . . . . . . . . . . . . . . 30
10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 31
11. References . . . . . . . . . . . . . . . . . . . . . . . . . 31
11.1. Normative References . . . . . . . . . . . . . . . . . . 31
11.2. Informative References . . . . . . . . . . . . . . . . . 33
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 34
1. Introduction
To process YANG-Push Notification messages at a YANG-Push Receiver,
as described in Section 3.7 of [RFC8641], the Publisher's instance of
the 'ietf-yang-library' module [RFC8525] must be queried whenever a
Subscription state change Notification, as specified in Section 2.7
of [RFC8639], is received. This query is necessary to determine
whether the semantics of the YANG module(s) referenced by the
Subscription have changed. To enable the Receiver to make this
determination without querying the Publisher's YANG library after
every Subscription state-change Notification, the Notification needs
to include a semantic reference to the relevant YANG module(s) and
the associated XPath expression or subtree selection.
This specification is primarily intended for YANG-Push Configured
Subscriptions, as defined in Section 2.5 of [RFC8639], because the
schema of a YANG-Push Publisher datastore may change after a
Configured Subscription has been established and the 'subscription-
started' Notification has already been sent to the Receiver. Without
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the mechanisms defined in this document, a subscriber cannot
constrain the supported YANG module revision or version and is not
notified when the YANG module revision or version associated with the
YANG-Push Subscription changes. Although these mechanisms are
primarily designed for YANG-Push Configured Subscriptions, the
extensions defined in Section 3 for 'subscription-started'
Notifications are equally applicable to Dynamic Subscriptions, as
defined in Section 2.4 of [RFC8639].
This semantic reference is available when the Subscription is
established as described in Section 2.4 and 2.5 of [RFC8639] and
streamed from the Publisher to the Receiver with the Subscription
state change Notifications, as described in Section 2.7 of [RFC8639].
For each Subscription, a locally unique Subscription ID, as described
in Section 4.3.2 of [RFC8641], is issued and streamed as metadata
with the Notification message in the YANG-Push message header.
The YANG module revision statement is specified in Section 7.1.9 of
[RFC7950]. In the revision-based model, changes to a module are
expected to preserve compatibility with previous revisions.
Section 3.1 of [I-D.ietf-netmod-yang-module-versioning] defines an
alternative semantic versioning model, as specified in
[I-D.ietf-netmod-yang-semver], in which a newer version may be either
backward compatible or non-backward compatible. Non-backward-
compatible changes are explicitly indicated using the 'non-backwards-
compatible' keyword.
The YANG Notifications Subscription mechanism defined in [RFC8641]
does not include the YANG module revision. Hence, when a network
node is upgraded, the subscribed YANG module revision may have
changed, and might consequently break the data processing pipeline
since the YANG-Push Receiver may not be aware of this change.
This document extends the current YANG Notifications Subscription
mechanism to allow Subscriptions to be constrained either to a
specific YANG module revision or to the latest semantic version of a
module that preserves backward compatibility.
The Subscription state change 'subscription-started' and
'subscription-modified' Notification messages are also extended to
include the YANG module 'revision', 'version', and YANG library
'content-id'. Changes in the 'revision' and 'version' fields allow a
YANG-Push Receiver to detect whenever the subscribed YANG module has
changed. Changes in yang-library-content-id indicates that YANG
module(s) on the network management Server of the YANG-Push Publisher
has or have changed.
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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 terms "subscriber", "subscription", "dynamic subscription",
"configured subscription", "publisher", "receiver" and "notification
message" are used as defined in [RFC8639].
The terms "client", and "server" are used as defined in [RFC8342].
The terms "YANG library" and "YANG library content identifier" are
used as defined in [RFC8525].
2. Subscription Policy Extension
The ability to configure or establish a Dynamic Subscription can be
constrained to particular module versions or revisions using the
following fields that are defined in the 'ietf-yang-push-revision'
YANG module:
module: Specifies the YANG module names to which the Subscription is
restricted, based on either a module revision or a semantic
version.
revision: Restricts the Subscription to a specific YANG module
revision. Example: "2014-05-08".
version: Restricts the Subscription to the latest compatible YANG
module semantic version referenced to. Example: "2.0.0".
When a NETCONF client creates or modifies a Subscription, either by
updating the Subscription configuration or by invoking the
'establish-subscription' or 'modify-subscription' RPCs, and the
NETCONF server does not support the specified revision or version in
the request, the server MUST return an RPC reply containing an <rpc-
error> element, as defined in Section 4.3 of [RFC6241], with the
error information populated as follows:
* an "error-type" node of "application".
* an "error-tag" node whose value is a string that corresponds to an
identity associated with the error.
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+===================================+==================+
| Error identity | Uses "error-tag" |
+===================================+==================+
| revision-unsupported | invalid-value |
+-----------------------------------+------------------+
| version-unsupported | invalid-value |
+-----------------------------------+------------------+
| incompatible-revision-and-version | invalid-value |
+-----------------------------------+------------------+
Table 1: General Subscription Error Identities and
Associated "error-tag" Use
The YANG-Push Publisher MUST NOT send Notifications if the 'revision'
or 'version' of the YANG module name in the Subscription policy
configuration does not match with the YANG library [RFC8525].
Figure 1 provides an example of a Dynamic periodic YANG-Push
"establish-subscription" RPC call with YANG revision and datastore-
xpath-filter. Figure 2 shows the response when the RPC has been
accepted by the NETCONF Server and, alternatively, Figure 3 presents
the error sent by the NETCONF Server when the revision is not
supported.
<rpc message-id="101"
xmlns:netconf="urn:ietf:params:xml:ns:netconf:base:1.0">
<establish-subscription
xmlns="urn:ietf:params:xml:ns:yang:ietf-subscribed-notifications"
xmlns:yp="urn:ietf:params:xml:ns:yang:ietf-yang-push"
xmlns:ypr="urn:ietf:params:xml:ns:yang:ietf-yang-push-revision">
<yp:datastore
xmlns:ds="urn:ietf:params:xml:ns:yang:ietf-datastores">
ds:operational
</yp:datastore>
<yp:datastore-xpath-filter
xmlns:ex="https://example.com/sample-data/1.0">
/ex:foo
</yp:datastore-xpath-filter>
<ypr:module-version>
<ypr:name>foo</ypr:name>
<ypr:revision>2023-09-17</ypr:revision>
</ypr:module-version>
<yp:periodic>
<yp:period>500</yp:period>
</yp:periodic>
</establish-subscription>
</rpc>
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Figure 1: Dynamic YANG-Push subscription
<rpc-reply message-id="101"
xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<id
xmlns="urn:ietf:params:xml:ns:yang:ietf-subscribed-notifications">
52
</id>
</rpc-reply>
Figure 2: Example of a successful response for the 'establish-
subscription' RPC request
<rpc-reply message-id="101"
xmlns="urn:ietf:params:xml:ns:netconf:base:1.0"
xmlns:yp="urn:ietf:params:xml:ns:yang:ietf-subscribed-notifications"
xmlns:ypr="urn:ietf:params:xml:ns:yang:ietf-yang-push-revision"
xmlns:ex="https://example.com/sample-data/1.0">
<rpc-error>
<error-type>application</error-type>
<error-tag>operation-failed</error-tag>
<error-severity>error</error-severity>
<error-path>
/ex:foo
</error-path>
<error-info>
<yp:establish-subscription-error-datastore>
<yp:reason>
ypr:revision-unsupported
</yp:reason>
</yp:establish-subscription-error-datastore>
</error-info>
</rpc-error>
</rpc-reply>
Figure 3: Example for an unsuccessful response for the
'establish-subscription' RPC request
Figure 4 provides an example of configured periodic YANG-Push
Subscription with YANG revision and datastore-xpath-filter.
=============== NOTE: '\' line wrapping per RFC 8792 ================
<rpc message-id="101"
xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<edit-config>
<target>
<running/>
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</target>
<config>
<subscriptions
xmlns="urn:ietf:params:xml:ns:yang:ietf-subscribed-notifications"
xmlns:yp="urn:ietf:params:xml:ns:yang:ietf-yang-push"
xmlns:ds="urn:ietf:params:xml:ns:yang:ietf-datastores"
xmlns:if="urn:ietf:params:xml:ns:yang:ietf-interfaces"
xmlns:ypr="urn:ietf:params:xml:ns:yang:ietf-yang-push-revision"
xmlns:unt="urn:ietf:params:xml:ns:yang:ietf-udp-notif-transport"
xmlns:snr="urn:ietf:params:xml:ns:yang:ietf-subscribed-notif-recei\
vers"
>
<subscription>
<id>53</id>
<yp:datastore>ds:operational</yp:datastore>
<yp:datastore-xpath-filter>
/if:interfaces
</yp:datastore-xpath-filter>
<ypr:module-version-subs>
<name>ietf-interfaces</name>
<revision>2018-02-20</revision>
</ypr:module-version-subs>
<transport>unt:udp-notif</transport>
<encoding>encode-json</encoding>
<receivers>
<receiver>
<name>subscription-specific-receiver-def</name>
<snr:receiver-instance-ref>
global-udp-notif-receiver-def
</snr:receiver-instance-ref>
</receiver>
</receivers>
<yp:periodic>
<period>6000</period>
</yp:periodic>
</subscription>
<snr:receiver-instances>
<receiver-instance>
<name>global-udp-notif-receiver-def</name>
<unt:udp-notif-receiver>
<address>192.0.5.1</address>
<port>12345</port>
<enable-segmentation>true</enable-segmentation>
<max-segment-size>1400</max-segment-size>
</unt:udp-notif-receiver>
</receiver-instance>
</snr:receiver-instances>
</subscriptions>
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</config>
</edit-config>
</rpc>
Figure 4: Configured YANG-Push subscription
3. Subscription State Change Notification Extension
Besides the Subscription ID and the xpath or subtree filter
reference, as described in Section 2.7 of [RFC8639], the following
metadata nodes are part of a 'subscription-started' or 'subscription-
modified' Subscription state change Notifications.
module: Describes the YANG module names from the Subscription path
for the related streamed content.
revision: Describes the YANG module revision as specified in
Section 7.1.9 of [RFC7950] for the related streamed content.
version: Describes the YANG module semantic version as specified in
[I-D.ietf-netmod-yang-semver] for the related streamed content.
yang-library-content-id: Contains the YANG library content
identifier [RFC8525] which is an implementation-specific
identifier representing the current information in the YANG
library on a specific Server.
Figure 5 provides an example of a 'subscription-modified'
Subscription state change Notification message with the YANG module
name, revision, version and datastore-xpath-filter for tracking the
operational status of a single Ethernet interface (per [RFC8343]).
This Subscription state change Notification message is encoded in XML
[W3C.REC-xml-20081126] over the Network Configuration Protocol
(NETCONF) as per [RFC8640].
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<notification xmlns="urn:ietf:params:xml:ns:netconf:notification:1.0">
<eventTime>2023-01-03T10:00:00Z</eventTime>
<subscription-modified
xmlns="urn:ietf:params:xml:ns:yang:ietf-subscribed-notifications">
<id>101</id>
<stream-xpath-filter
xmlns:if="urn:ietf:params:xml:ns:yang:ietf-interfaces">
/if:interfaces
</stream-xpath-filter>
<stream>NETCONF</stream>
<module-version
xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-push-revision">
<name>ietf-interfaces</name>
<revision>2018-02-20</revision>
<version>2.0.0</version>
</module-version>
<yang-library-content-id
xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-push-revision">
1
</yang-library-content-id>
</subscription-modified>
</notification>
Figure 5: XML Push Example for a subscription-modified
Notification message
Figure 6 provides an example of a JSON encoded, [RFC7951],
Subscription state change Notification message that is sent over UDP-
based transport [I-D.ietf-netconf-udp-notif]. The same Subscription
state change Notification can be sent over HTTPS-based transport
[I-D.ietf-netconf-https-notif], using the namespace specified in
Section 4.1 of [I-D.ietf-netconf-https-notif].
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{
"ietf-notification:notification" : {
"eventTime": "2023-01-03T10:00:00Z",
"ietf-subscribed-notifications:subscription-modified": {
"id": 101,
"stream-xpath-filter": "/ietf-interfaces:interfaces",
"stream": "NETCONF",
"ietf-yang-push-revision:module-version": [
{
"name": "ietf-interfaces",
"revision": "2018-02-20",
"version": "2.0.0"
}
],
"ietf-yang-push-revision:yang-library-content-id": "1"
}
}
}
Figure 6: JSON Push Example for a subscription-modified
Notification message
4. Discovering "ietf-yang-push-revision" Support
A Client can discover whether the Server supports the 'ietf-yang-
push-revision' model through the capabilities model defined in
[RFC9196]. This document extends the 'ietf-notification-
capabilities' model [RFC9196] with:
* A leaf 'yang-push-module-revision-supported', stating that the
YANG-Push Subscription state change Notifications are extended
with 'revision', 'version' and 'yang-library-content-id'
extensions.
The YANG models defined in Section 5.2 augments the 'ietf-
notification-capabilities' model with the leaf listed above.
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module: ietf-system-capabilities
+--ro system-capabilities
+--ro datastore-capabilities* [datastore]
| +--ro datastore
| | -> /yanglib:yang-library/datastore/name
| +--ro per-node-capabilities* []
| +--ro (node-selection)?
| | +--:(node-selector)
| | +--ro node-selector?
| | nacm:node-instance-identifier
| +--ro notc:subscription-capabilities
| +--ro notc:max-nodes-per-update? uint32
| +--ro notc:periodic-notifications-supported?
| | notification-support
| +--ro (notc:update-period)?
| | +--:(notc:minimum-update-period)
| | | +--ro notc:minimum-update-period? uint32
| | +--:(notc:supported-update-period)
| | +--ro notc:supported-update-period* uint32
| +--ro notc:on-change-supported?
| | notification-support {yp:on-change}?
| +--ro notc:minimum-dampening-period? uint32
| | {yp:on-change}?
| +--ro notc:supported-excluded-change-type* union
| {yp:on-change}?
+--ro notc:subscription-capabilities
+--ro notc:max-nodes-per-update? uint32
+--ro notc:periodic-notifications-supported?
| notification-support
+--ro (notc:update-period)?
| +--:(notc:minimum-update-period)
| | +--ro notc:minimum-update-period? uint32
| +--:(notc:supported-update-period)
| +--ro notc:supported-update-period* uint32
+--ro notc:on-change-supported?
| notification-support {yp:on-change}?
+--ro notc:minimum-dampening-period? uint32
| {yp:on-change}?
+--ro notc:supported-excluded-change-type* union
| {yp:on-change}?
+--ro ypr:yang-push-module-revision-supported? boolean
This model can be retrieved via a NETCONF <get> RPC.
5. The "ietf-yang-push-revision" Module
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5.1. Data Model Overview
This 'ietf-yang-push-revision' YANG module augments the 'ietf-
subscribed-notifications' module with the 'name', 'revision',
'version' and 'yang-library-content-id' in the 'subscription-started'
and 'subscription-modified' Subscription state change Notifications
and the ability to define the 'revision' and 'version' in the
'establish-subscription' and 'modify-subscription' RPCs in the
datastore push Subscription.
5.1.1. Tree View
The following is the YANG tree diagram [RFC8340] for the 'ietf-yang-
push-revision' YANG module
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module: ietf-yang-push-revision
augment /sn:establish-subscription/sn:input:
+---w module-version-subs* [name]
+---w name yang:yang-identifier
+---w (revision-version)?
+--:(revision)
| +---w revision? rev:revision-date
+--:(version)
+---w version? ysv:version
augment /sn:modify-subscription/sn:input:
+---w module-version-subs* [name]
+---w name yang:yang-identifier
+---w (revision-version)?
+--:(revision)
| +---w revision? rev:revision-date
+--:(version)
+---w version? ysv:version
augment /sn:subscription-started:
+--ro module-version* [name]
| +--ro name yang:yang-identifier
| +--ro revision rev:revision-date
| +--ro version? ysv:version
+--ro yang-library-content-id?
-> /yanglib:yang-library/content-id
augment /sn:subscription-modified:
+--ro module-version* [name]
| +--ro name yang:yang-identifier
| +--ro revision rev:revision-date
| +--ro version? ysv:version
+--ro yang-library-content-id?
-> /yanglib:yang-library/content-id
augment /sn:subscriptions/sn:subscription:
+--rw module-version-subs* [name]
+--rw name yang:yang-identifier
+--rw (revision-version)?
+--:(revision)
| +--rw revision? rev:revision-date
+--:(version)
+--rw version? ysv:version
augment /sysc:system-capabilities/notc:subscription-capabilities:
+--ro yang-push-module-revision-supported? boolean
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5.1.2. Full Tree View
The following is the YANG tree diagram [RFC8340] for the 'ietf-yang-
push-revision' augmentation of the 'ietf-subscribed-notifications'
and its 'ietf-yang-push' import, including the RPCs and
Notifications.
module: ietf-subscribed-notifications
+--ro streams
| +--ro stream* [name]
| +--ro name string
| +--ro description? string
| +--ro replay-support? empty {replay}?
| +--ro replay-log-creation-time yang:date-and-time
| | {replay}?
| +--ro replay-log-aged-time? yang:date-and-time
| {replay}?
+--rw filters
| +--rw stream-filter* [name]
| | +--rw name string
| | +--rw (filter-spec)?
| | +--:(stream-subtree-filter)
| | | +--rw stream-subtree-filter? <anydata> {subtree}?
| | +--:(stream-xpath-filter)
| | +--rw stream-xpath-filter? yang:xpath1.0 {xpath}?
| +--rw yp:selection-filter* [filter-id]
| +--rw yp:filter-id string
| +--rw (yp:filter-spec)?
| +--:(yp:datastore-subtree-filter)
| | +--rw yp:datastore-subtree-filter? <anydata>
| | {sn:subtree}?
| +--:(yp:datastore-xpath-filter)
| +--rw yp:datastore-xpath-filter? yang:xpath1.0
| {sn:xpath}?
+--rw subscriptions
+--rw subscription* [id]
+--rw id
| subscription-id
+--rw (target)
| +--:(stream)
| | +--rw (stream-filter)?
| | | +--:(by-reference)
| | | | +--rw stream-filter-name
| | | | stream-filter-ref
| | | +--:(within-subscription)
| | | +--rw (filter-spec)?
| | | +--:(stream-subtree-filter)
| | | | +--rw stream-subtree-filter?
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| | | | <anydata> {subtree}?
| | | +--:(stream-xpath-filter)
| | | +--rw stream-xpath-filter?
| | | yang:xpath1.0 {xpath}?
| | +--rw stream
| | | stream-ref
| | +--ro replay-start-time?
| | | yang:date-and-time {replay}?
| | +--rw configured-replay? empty
| | {configured,replay}?
| +--:(yp:datastore)
| +--rw yp:datastore
| | identityref
| +--rw (yp:selection-filter)?
| +--:(yp:by-reference)
| | +--rw yp:selection-filter-ref
| | selection-filter-ref
| +--:(yp:within-subscription)
| +--rw (yp:filter-spec)?
| +--:(yp:datastore-subtree-filter)
| | +--rw yp:datastore-subtree-filter?
| | <anydata> {sn:subtree}?
| +--:(yp:datastore-xpath-filter)
| +--rw yp:datastore-xpath-filter?
| yang:xpath1.0 {sn:xpath}?
+--rw stop-time?
| yang:date-and-time
+--rw dscp?
| inet:dscp {dscp}?
+--rw weighting? uint8
| {qos}?
+--rw dependency?
| subscription-id {qos}?
+--rw transport?
| transport {configured}?
+--rw encoding?
| encoding
+--rw purpose? string
| {configured}?
+--rw (notification-message-origin)? {configured}?
| +--:(interface-originated)
| | +--rw source-interface?
| | if:interface-ref {interface-designation}?
| +--:(address-originated)
| +--rw source-vrf?
| | -> /ni:network-instances/network-instance/name
| | {supports-vrf}?
| +--rw source-address?
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| inet:ip-address-no-zone
+--ro configured-subscription-state?
| enumeration {configured}?
+--rw receivers
| +--rw receiver* [name]
| +--rw name string
| +--ro sent-event-records?
| | yang:zero-based-counter64
| +--ro excluded-event-records?
| | yang:zero-based-counter64
| +--ro state enumeration
| +---x reset {configured}?
| +--ro output
| +--ro time yang:date-and-time
+--rw (yp:update-trigger)?
| +--:(yp:periodic)
| | +--rw yp:periodic!
| | +--rw yp:period centiseconds
| | +--rw yp:anchor-time? yang:date-and-time
| +--:(yp:on-change) {on-change}?
| +--rw yp:on-change!
| +--rw yp:dampening-period? centiseconds
| +--rw yp:sync-on-start? boolean
| +--rw yp:excluded-change* change-type
+--rw ypr:module-version-subs* [name]
+--rw ypr:name yang:yang-identifier
+--rw (ypr:revision-version)?
+--:(ypr:revision)
| +--rw ypr:revision? rev:revision-date
+--:(ypr:version)
+--rw ypr:version? ysv:version
rpcs:
+---x establish-subscription
| +---w input
| | +---w (target)
| | | +--:(stream)
| | | | +---w (stream-filter)?
| | | | | +--:(by-reference)
| | | | | | +---w stream-filter-name
| | | | | | stream-filter-ref
| | | | | +--:(within-subscription)
| | | | | +---w (filter-spec)?
| | | | | +--:(stream-subtree-filter)
| | | | | | +---w stream-subtree-filter?
| | | | | | <anydata> {subtree}?
| | | | | +--:(stream-xpath-filter)
| | | | | +---w stream-xpath-filter?
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| | | | | yang:xpath1.0 {xpath}?
| | | | +---w stream
| | | | | stream-ref
| | | | +---w replay-start-time?
| | | | yang:date-and-time {replay}?
| | | +--:(yp:datastore)
| | | +---w yp:datastore
| | | | identityref
| | | +---w (yp:selection-filter)?
| | | +--:(yp:by-reference)
| | | | +---w yp:selection-filter-ref
| | | | selection-filter-ref
| | | +--:(yp:within-subscription)
| | | +---w (yp:filter-spec)?
| | | +--:(yp:datastore-subtree-filter)
| | | | +---w yp:datastore-subtree-filter?
| | | | <anydata> {sn:subtree}?
| | | +--:(yp:datastore-xpath-filter)
| | | +---w yp:datastore-xpath-filter?
| | | yang:xpath1.0 {sn:xpath}?
| | +---w stop-time?
| | | yang:date-and-time
| | +---w dscp?
| | | inet:dscp {dscp}?
| | +---w weighting?
| | | uint8 {qos}?
| | +---w dependency?
| | | subscription-id {qos}?
| | +---w encoding?
| | | encoding
| | +---w (yp:update-trigger)?
| | | +--:(yp:periodic)
| | | | +---w yp:periodic!
| | | | +---w yp:period centiseconds
| | | | +---w yp:anchor-time? yang:date-and-time
| | | +--:(yp:on-change) {on-change}?
| | | +---w yp:on-change!
| | | +---w yp:dampening-period? centiseconds
| | | +---w yp:sync-on-start? boolean
| | | +---w yp:excluded-change* change-type
| | +---w ypr:module-version-subs* [name]
| | +---w ypr:name yang:yang-identifier
| | +---w (ypr:revision-version)?
| | +--:(ypr:revision)
| | | +---w ypr:revision? rev:revision-date
| | +--:(ypr:version)
| | +---w ypr:version? ysv:version
| +--ro output
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| +--ro id subscription-id
| +--ro replay-start-time-revision? yang:date-and-time
| {replay}?
+---x modify-subscription
| +---w input
| +---w id
| | subscription-id
| +---w (target)
| | +--:(stream)
| | | +---w (stream-filter)?
| | | +--:(by-reference)
| | | | +---w stream-filter-name
| | | | stream-filter-ref
| | | +--:(within-subscription)
| | | +---w (filter-spec)?
| | | +--:(stream-subtree-filter)
| | | | +---w stream-subtree-filter?
| | | | <anydata> {subtree}?
| | | +--:(stream-xpath-filter)
| | | +---w stream-xpath-filter?
| | | yang:xpath1.0 {xpath}?
| | +--:(yp:datastore)
| | +---w yp:datastore
| | | identityref
| | +---w (yp:selection-filter)?
| | +--:(yp:by-reference)
| | | +---w yp:selection-filter-ref
| | | selection-filter-ref
| | +--:(yp:within-subscription)
| | +---w (yp:filter-spec)?
| | +--:(yp:datastore-subtree-filter)
| | | +---w yp:datastore-subtree-filter?
| | | <anydata> {sn:subtree}?
| | +--:(yp:datastore-xpath-filter)
| | +---w yp:datastore-xpath-filter?
| | yang:xpath1.0 {sn:xpath}?
| +---w stop-time?
| | yang:date-and-time
| +---w (yp:update-trigger)?
| | +--:(yp:periodic)
| | | +---w yp:periodic!
| | | +---w yp:period centiseconds
| | | +---w yp:anchor-time? yang:date-and-time
| | +--:(yp:on-change) {on-change}?
| | +---w yp:on-change!
| | +---w yp:dampening-period? centiseconds
| +---w ypr:module-version-subs* [name]
| +---w ypr:name yang:yang-identifier
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| +---w (ypr:revision-version)?
| +--:(ypr:revision)
| | +---w ypr:revision? rev:revision-date
| +--:(ypr:version)
| +---w ypr:version? ysv:version
+---x delete-subscription
| +---w input
| +---w id subscription-id
+---x kill-subscription
+---w input
+---w id subscription-id
notifications:
+---n replay-completed {replay}?
| +--ro id subscription-id
+---n subscription-completed {configured}?
| +--ro id subscription-id
+---n subscription-modified
| +--ro id
| | subscription-id
| +--ro (target)
| | +--:(stream)
| | | +--ro (stream-filter)?
| | | | +--:(by-reference)
| | | | | +--ro stream-filter-name
| | | | | stream-filter-ref
| | | | +--:(within-subscription)
| | | | +--ro (filter-spec)?
| | | | +--:(stream-subtree-filter)
| | | | | +--ro stream-subtree-filter?
| | | | | <anydata> {subtree}?
| | | | +--:(stream-xpath-filter)
| | | | +--ro stream-xpath-filter?
| | | | yang:xpath1.0 {xpath}?
| | | +--ro stream
| | | | stream-ref
| | | +--ro replay-start-time?
| | | yang:date-and-time {replay}?
| | +--:(yp:datastore)
| | +--ro yp:datastore
| | | identityref
| | +--ro (yp:selection-filter)?
| | +--:(yp:by-reference)
| | | +--ro yp:selection-filter-ref
| | | selection-filter-ref
| | +--:(yp:within-subscription)
| | +--ro (yp:filter-spec)?
| | +--:(yp:datastore-subtree-filter)
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| | | +--ro yp:datastore-subtree-filter?
| | | <anydata> {sn:subtree}?
| | +--:(yp:datastore-xpath-filter)
| | +--ro yp:datastore-xpath-filter?
| | yang:xpath1.0 {sn:xpath}?
| +--ro stop-time?
| | yang:date-and-time
| +--ro dscp?
| | inet:dscp {dscp}?
| +--ro weighting? uint8
| | {qos}?
| +--ro dependency?
| | subscription-id {qos}?
| +--ro transport?
| | transport {configured}?
| +--ro encoding?
| | encoding
| +--ro purpose? string
| | {configured}?
| +--ro (yp:update-trigger)?
| | +--:(yp:periodic)
| | | +--ro yp:periodic!
| | | +--ro yp:period centiseconds
| | | +--ro yp:anchor-time? yang:date-and-time
| | +--:(yp:on-change) {on-change}?
| | +--ro yp:on-change!
| | +--ro yp:dampening-period? centiseconds
| | +--ro yp:sync-on-start? boolean
| | +--ro yp:excluded-change* change-type
| +--ro ypr:module-version* [name]
| | +--ro ypr:name yang:yang-identifier
| | +--ro ypr:revision rev:revision-date
| | +--ro ypr:version? ysv:version
| +--ro ypr:yang-library-content-id?
| -> /yanglib:yang-library/content-id
+---n subscription-resumed
| +--ro id subscription-id
+---n subscription-started {configured}?
| +--ro id
| | subscription-id
| +--ro (target)
| | +--:(stream)
| | | +--ro (stream-filter)?
| | | | +--:(by-reference)
| | | | | +--ro stream-filter-name
| | | | | stream-filter-ref
| | | | +--:(within-subscription)
| | | | +--ro (filter-spec)?
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| | | | +--:(stream-subtree-filter)
| | | | | +--ro stream-subtree-filter?
| | | | | <anydata> {subtree}?
| | | | +--:(stream-xpath-filter)
| | | | +--ro stream-xpath-filter?
| | | | yang:xpath1.0 {xpath}?
| | | +--ro stream
| | | | stream-ref
| | | +--ro replay-start-time?
| | | | yang:date-and-time {replay}?
| | | +--ro replay-previous-event-time?
| | | yang:date-and-time {replay}?
| | +--:(yp:datastore)
| | +--ro yp:datastore
| | | identityref
| | +--ro (yp:selection-filter)?
| | +--:(yp:by-reference)
| | | +--ro yp:selection-filter-ref
| | | selection-filter-ref
| | +--:(yp:within-subscription)
| | +--ro (yp:filter-spec)?
| | +--:(yp:datastore-subtree-filter)
| | | +--ro yp:datastore-subtree-filter?
| | | <anydata> {sn:subtree}?
| | +--:(yp:datastore-xpath-filter)
| | +--ro yp:datastore-xpath-filter?
| | yang:xpath1.0 {sn:xpath}?
| +--ro stop-time?
| | yang:date-and-time
| +--ro dscp?
| | inet:dscp {dscp}?
| +--ro weighting? uint8
| | {qos}?
| +--ro dependency?
| | subscription-id {qos}?
| +--ro transport?
| | transport {configured}?
| +--ro encoding?
| | encoding
| +--ro purpose? string
| | {configured}?
| +--ro (yp:update-trigger)?
| | +--:(yp:periodic)
| | | +--ro yp:periodic!
| | | +--ro yp:period centiseconds
| | | +--ro yp:anchor-time? yang:date-and-time
| | +--:(yp:on-change) {on-change}?
| | +--ro yp:on-change!
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| | +--ro yp:dampening-period? centiseconds
| | +--ro yp:sync-on-start? boolean
| | +--ro yp:excluded-change* change-type
| +--ro ypr:module-version* [name]
| | +--ro ypr:name yang:yang-identifier
| | +--ro ypr:revision rev:revision-date
| | +--ro ypr:version? ysv:version
| +--ro ypr:yang-library-content-id?
| -> /yanglib:yang-library/content-id
+---n subscription-suspended
| +--ro id subscription-id
| +--ro reason identityref
+---n subscription-terminated
+--ro id subscription-id
+--ro reason identityref
5.2. YANG Module
The YANG module has two leafs augmenting the model of Subscription to
YANG Notifications [RFC8639] and imports YANG modules defined in
[RFC9911], [RFC8525], [RFC9196],
[I-D.ietf-netmod-yang-module-versioning] and
[I-D.ietf-netmod-yang-semver].
<CODE BEGINS> file "ietf-yang-push-revision@2026-07-02.yang"
module ietf-yang-push-revision {
yang-version 1.1;
namespace
"urn:ietf:params:xml:ns:yang:ietf-yang-push-revision";
prefix ypr;
import ietf-subscribed-notifications {
prefix sn;
reference
"RFC 8639: Subscription to YANG Notifications";
}
import ietf-yang-revisions {
prefix rev;
reference
"RFC YYYY: draft-ietf-netmod-yang-module-versioning-13,
Updated YANG Module Revision Handling";
}
import ietf-yang-types {
prefix yang;
rev:recommended-min-date "2025-12-22";
reference
"RFC 9911: Common YANG Data Types.";
}
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import ietf-yang-semver {
prefix ysv;
reference
"RFC ZZZZ: draft-ietf-netmod-yang-semver-23, YANG Semantic
Versioning";
}
import ietf-yang-library {
prefix yanglib;
reference
"RFC 8525: YANG Library";
}
import ietf-system-capabilities {
prefix sysc;
reference
"RFC 9196: YANG Modules Describing Capabilities for
Systems and Datastore Update Notifications";
}
import ietf-notification-capabilities {
prefix notc;
reference
"RFC 9196: YANG Modules Describing Capabilities for
Systems and Datastore Update Notifications";
}
organization "IETF NETCONF (Network Configuration) Working Group";
contact
"WG Web: <http:/tools.ietf.org/wg/netconf/>
WG List: <mailto:netconf@ietf.org>
Authors: Thomas Graf
<mailto:thomas.graf@swisscom.com>
Benoit Claise
<mailto:benoit.claise@huawei.com>
Alex Huang Feng
<mailto:alex.huang-feng@t-systems.com>";
description
"Defines YANG-Push event notification header with the revision
and the version. Adds the support of the revision and
version selection in the YANG-Push subscription RPCs.
Copyright (c) 2026 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
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Relating to IETF Documents
(https://trustee.ietf.org/license-info).
All revisions of IETF and IANA published modules can be found
at the YANG Parameters registry
(https://www.iana.org/assignments/yang-parameters).
This version of this YANG module is part of RFC XXXX; see the RFC
itself for full legal notices.
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 (RFC 2119) (RFC 8174) when, and only when,
they appear in all capitals, as shown here.";
revision 2026-07-02 {
description
"First revision";
reference
"RFC XXXX: Support of Versioning in YANG Notifications
Subscription";
}
// Identities
identity revision-unsupported {
base sn:establish-subscription-error;
base sn:modify-subscription-error;
description
"Revision not supported. This failure can be due to
subscribing to a specific revision not supported by the
publisher.";
}
identity version-unsupported {
base sn:establish-subscription-error;
base sn:modify-subscription-error;
description
"Specific version not supported. This failure can be due to
subscribing to a specific version not supported by the
publisher.";
}
identity incompatible-revision-and-version {
base sn:establish-subscription-error;
base sn:modify-subscription-error;
description
"The combination of revision and version are
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incompatible. This failure happens when the revision and the
version are both specified in the RPC and the YANG
module supported by the publisher does not support one of them.";
}
grouping yang-push-module-version-subs {
description
"This grouping combines the module name, the revision and
version leafs. This grouping is to be used for
configuration and the leafs are not mandatory.";
leaf name {
type yang:yang-identifier;
description
"This references the YANG module name.";
}
choice revision-version {
description
"Specifies the revision or version of the YANG module sent
in the subscription.";
case revision {
leaf revision {
type rev:revision-date;
description
"This references the YANG module revision to be sent in the
subscription.";
}
}
case version {
leaf version {
type ysv:version;
description
"This references the YANG module semantic version to be sent
in the subscription.";
}
}
}
}
grouping yang-push-module-version-notif {
description
"This grouping combines the module name, the revision and
version leafs. This grouping is to be used for
read-only cases such as the content of YANG-Push Notifications.
The name and revision are mandatory and MUST be present
in the data.";
leaf name {
type yang:yang-identifier;
config false;
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mandatory true;
description
"This references the YANG module name.";
}
leaf revision {
type rev:revision-date;
config false;
mandatory true;
description
"This references the YANG module revision of the sent
notification message.";
}
leaf version {
type ysv:version;
description
"This references the YANG module semantic version of the
sent notification message.";
}
}
grouping yang-push-module-version-notif-list {
description
"This grouping defines a list of yang-push-module-version-notif
grouping.";
list module-version {
key "name";
config false;
description
"List of yang-push-module-version grouping. The revision is
not configurable.";
uses ypr:yang-push-module-version-notif;
}
leaf yang-library-content-id {
type leafref {
path "/yanglib:yang-library/yanglib:content-id";
}
config false;
description
"Contains the YANG library content identifier
information.";
reference
"RFC 8525: YANG Library";
}
}
grouping yang-push-module-version-subs-list {
description
"This grouping defines a list of yang-push-module-version-subs
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grouping.";
list module-version-subs {
key "name";
description
"List of yang-push-module-version-subs grouping. The
revision is configurable.";
uses ypr:yang-push-module-version-subs;
}
}
// Subscription parameters
augment "/sn:establish-subscription/sn:input" {
description
"Augment the establish-subscription RPC from the
ietf-subscribed-notifications YANG module with the
yang-push-module-version-subs-list grouping.";
uses ypr:yang-push-module-version-subs-list;
}
augment "/sn:modify-subscription/sn:input" {
description
"Augment the modify-subscription RPC from the
ietf-subscribed-notifications YANG module with the
yang-push-module-version-subs-list grouping.";
uses ypr:yang-push-module-version-subs-list;
}
// Subscription notifications
augment "/sn:subscription-started" {
description
"Augment the subscription-started notification from the
ietf-subscribed-notifications YANG module with the
yang-push-module-version-notif-list grouping.";
uses ypr:yang-push-module-version-notif-list;
}
augment "/sn:subscription-modified" {
description
"Augment the subscription-modified notification from the
ietf-subscribed-notifications YANG module with the
yang-push-module-version-notif-list grouping.";
uses ypr:yang-push-module-version-notif-list;
}
// Subscription container
augment "/sn:subscriptions/sn:subscription" {
description
"Augment the subscriptions RPC container from the
ietf-subscribed-notifications YANG module with the
yang-push-module-version-subs-list grouping.";
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uses ypr:yang-push-module-version-subs-list;
}
// Subscription capabilities
augment "/sysc:system-capabilities/notc:subscription-capabilities" {
description
"Add system level capabilities";
leaf yang-push-module-revision-supported {
type boolean;
default true;
description
"Specifies whether the publisher supports exporting
revision and version in YANG-Push subscription state change
notifications. If set to true, publisher supports. If set to
false, publisher does not support.";
reference
"RFC XXXX: Support of Versioning in YANG Notifications
Subscription";
}
}
}
<CODE ENDS>
6. IANA Considerations
6.1. IETF XML Registry
This document registers the following URIs in the "IETF XML Registry"
[RFC3688]:
URI: urn:ietf:params:xml:ns:yang:ietf-yang-push-revision
Registrant Contact: The IESG.
XML: N/A; the requested URI is an XML namespace.
6.2. YANG Module Name
This document registers the following YANG modules in the 'YANG
Module Names' registry [RFC6020]:
name: ietf-yang-push-revision
namespace: urn:ietf:params:xml:ns:yang:ietf-yang-push-revision
prefix: ypr
reference: RFC-to-be
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7. Operational Considerations
The solution described in this document allows Subscription policies
to be constrained to a particular module revisions/versions that are
used by the Publisher before a Subscription is initiated. The
augmentations to the Subscription state change Notifications also
gives the Receiver additional context and confidence of the current
schema associated with a Subscription.
Section 2.5.1 of [RFC8639] describes the Subscription state machine
for Configured YANG-Push Subscriptions. It states that
'subscription-modified' condition is triggered when the Subscription
policy is being changed. Since this document proposes YANG version
and revision extensions in Subscription configuration and state
change notifications, it is expected that changes in YANG version and
revision of a Subscription during Subscription lifecycle accounts for
changes in Subscription policy and therefore MUST trigger
'subscription-modified' Subscription state change Notifications.
Note, that not all modules used or referenced under a Subscription
path are included in the Subscription state change Notification, and
hence, it is possible that the schema associated with a Subscription
MAY change without any corresponding change to the advertise module
revisions or versions. Therefore, the YANG Library content-id that
is also included in the Subscription state change Notifications
allows the Receiver to detect if there were changes to the device
schema. This includes changes not related to the Subscription path
as well. Take Figure 6 as example. The Subscription path is '/ietf-
interfaces:interfaces' and the listed YANG module name is 'ietf-
interfaces' with revision '2018-02-20' and version '2.0.0'. The
'ietf-interfaces' YANG module defined in Section 5 of [RFC8343] and
imports 'ietf-yang-types' YANG module. If 'ietf-interfaces' YANG
module version or revision would change during the Subscription
lifecycle, a YANG-Push Receiver would recognize the change since the
revision or version in the module-version and the YANG library
content-id has changed. However, if 'ietf-yang-types' YANG module
version or revision would change, a YANG-Push Receiver would only be
able to recognize the change using the YANG library content-id.
A YANG package [I-D.ietf-netmod-yang-packages], specifies a versioned
organizational structure used to manage a set of YANG modules that
collectively defines a package schema. For example, a YANG package
could contain a set of YANG modules required to implement a L3VPN
service on a network node. It offers therefore a complementary
information to the solution in this draft by describing how one
specific YANG module revision is part of a set of YANG modules.
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8. Implementation Status
Note to the RFC-Editor: Please remove this section before publishing.
8.1. Huawei VRP
Huawei implemented in Notification the 'module', 'revision' and
'version' extension as described in Section 3 for a YANG-Push
Publisher on UDP-based Transport for Configured Subscriptions
[I-D.ietf-netconf-udp-notif] in their VRP platform.
8.2. 6WIND VSR
6WIND implemented in Notification 'module', 'revision' and 'library-
content-id' extension as described in Section 3 for a YANG-Push
Publisher on UDP-based Transport for Configured Subscriptions
[I-D.ietf-netconf-udp-notif] in their VSR platform.
8.3. Cisco IOS XR
Cisco implemented in Notification 'module', 'revision' and 'library-
content-id' extension as described in Section 3 and 'module' and
'revision' in Subscription as described in Section 2 for a YANG-Push
Publisher on UDP-based Transport for Configured Subscriptions
[I-D.ietf-netconf-udp-notif] in their IOS XR platform.
9. Security Considerations
This section uses the template described in Section 3.7.1 of
[RFC9907].
The "ietf-yang-push-revision" YANG module defines a data model that
is designed to be accessed via YANG-based management protocols, such
as NETCONF [RFC6241] and RESTCONF [RFC8040]. These YANG-based
management protocols (1) have to use a secure transport layer (e.g.,
SSH [RFC6242], 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 reasonably
sensitive or vulnerable in some network environments. Write
operations (e.g., edit-config) and delete operations to these data
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nodes without proper protection or authentication can have a negative
effect on network operations. The following subtrees and data nodes
have particular sensitivities/vulnerabilities:
* /sn:establish-subscription/sn:input/ypr:module-version-subs
* /sn:modify-subscription/sn:input/ypr:module-version-subs
* /sn:subscriptions/sn:subscription/ypr:module-version-subs
The entries in the list above allow in a YANG-Push Subscription to
define the revision or version of a YANG module name. Access control
MUST be set so that only someone with proper access permissions has
the ability to access and modify this resource.
10. Acknowledgements
The authors would like to thank Qiufang Ma, Robert Wilton, Jian Ping
Zhang, Robert Wills, Reshad Rahman, Camilo Cardona Holger Keller,
Gabriele Galimberti, Mohit P. Tahiliani and Per Andersson for their
review and valuable comments.
11. References
11.1. Normative References
[I-D.ietf-netmod-yang-module-versioning]
Wilton, R., Rahman, R., Lengyel, B., Clarke, J., and J.
Sterne, "Updated YANG Module Revision Handling", Work in
Progress, Internet-Draft, draft-ietf-netmod-yang-module-
versioning-17, 29 June 2026,
<https://datatracker.ietf.org/doc/html/draft-ietf-netmod-
yang-module-versioning-17>.
[I-D.ietf-netmod-yang-semver]
Clarke, J., Wilton, R., Rahman, R., Lengyel, B., Sterne,
J., and B. Claise, "YANG Semantic Versioning", Work in
Progress, Internet-Draft, draft-ietf-netmod-yang-semver-
26, 7 May 2026, <https://datatracker.ietf.org/doc/html/
draft-ietf-netmod-yang-semver-26>.
[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>.
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[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>.
[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>.
[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>.
[RFC8525] Bierman, A., Bjorklund, M., Schoenwaelder, J., Watsen, K.,
and R. Wilton, "YANG Library", RFC 8525,
DOI 10.17487/RFC8525, March 2019,
<https://www.rfc-editor.org/info/rfc8525>.
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[RFC8639] Voit, E., Clemm, A., Gonzalez Prieto, A., Nilsen-Nygaard,
E., and A. Tripathy, "Subscription to YANG Notifications",
RFC 8639, DOI 10.17487/RFC8639, September 2019,
<https://www.rfc-editor.org/info/rfc8639>.
[RFC8641] Clemm, A. and E. Voit, "Subscription to YANG Notifications
for Datastore Updates", RFC 8641, DOI 10.17487/RFC8641,
September 2019, <https://www.rfc-editor.org/info/rfc8641>.
[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/info/rfc9000>.
[RFC9196] Lengyel, B., Clemm, A., and B. Claise, "YANG Modules
Describing Capabilities for Systems and Datastore Update
Notifications", RFC 9196, DOI 10.17487/RFC9196, February
2022, <https://www.rfc-editor.org/info/rfc9196>.
[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/info/rfc9907>.
[RFC9911] Schönwälder, J., Ed., "Common YANG Data Types", RFC 9911,
DOI 10.17487/RFC9911, December 2025,
<https://www.rfc-editor.org/info/rfc9911>.
11.2. Informative References
[I-D.ietf-netconf-https-notif]
Jethanandani, M. and K. Watsen, "An HTTPS-based Transport
for YANG Notifications", Work in Progress, Internet-Draft,
draft-ietf-netconf-https-notif-16, 30 June 2026,
<https://datatracker.ietf.org/doc/html/draft-ietf-netconf-
https-notif-16>.
[I-D.ietf-netconf-udp-notif]
Feng, A. H., Francois, P., Zhou, T., Graf, T., and P.
Lucente, "UDP-based Transport for Configured
Subscriptions", Work in Progress, Internet-Draft, draft-
ietf-netconf-udp-notif-25, 28 January 2026,
<https://datatracker.ietf.org/doc/html/draft-ietf-netconf-
udp-notif-25>.
[I-D.ietf-netmod-yang-packages]
Wilton, R., Rahman, R., Clarke, J., and J. Sterne, "YANG
Packages", Work in Progress, Internet-Draft, draft-ietf-
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netmod-yang-packages-07, 2 March 2026,
<https://datatracker.ietf.org/doc/html/draft-ietf-netmod-
yang-packages-07>.
[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>.
[RFC8343] Bjorklund, M., "A YANG Data Model for Interface
Management", RFC 8343, DOI 10.17487/RFC8343, March 2018,
<https://www.rfc-editor.org/info/rfc8343>.
[RFC8640] Voit, E., Clemm, A., Gonzalez Prieto, A., Nilsen-Nygaard,
E., and A. Tripathy, "Dynamic Subscription to YANG Events
and Datastores over NETCONF", RFC 8640,
DOI 10.17487/RFC8640, September 2019,
<https://www.rfc-editor.org/info/rfc8640>.
[W3C.REC-xml-20081126]
Bray, T., Paoli, J., Sperberg-McQueen, M., Maler, E., and
F. Yergeau, "Extensible Markup Language (XML) 1.0 (Fifth
Edition)", World Wide Web Consortium Recommendation REC-
xml-20081126, November 2008,
<https://www.w3.org/TR/2008/REC-xml-20081126>.
Authors' Addresses
Thomas Graf
Swisscom
Binzring 17
CH-8045 Zurich
Switzerland
Email: thomas.graf@swisscom.com
Benoit Claise
Huawei
Email: benoit@everything-ops.net
Alex Huang-Feng
Deutsche Telekom
Barcelona
Spain
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Email: alex.huang-feng@t-systems.com
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