A YANG Data Model for Collection Interval Capabilities
draft-yoon-ippm-collection-interval-capabilities-00
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| Document | Type | Active Internet-Draft (individual) | |
|---|---|---|---|
| Authors | Bin Yeong Yoon , Youngkil You | ||
| Last updated | 2026-07-05 | ||
| RFC stream | (None) | ||
| Intended RFC status | (None) | ||
| Formats | |||
| Yang Validation | 0 errors, 0 warnings | ||
| Stream | Stream state | (No stream defined) | |
| Consensus boilerplate | Unknown | ||
| RFC Editor Note | (None) | ||
| IESG | IESG state | I-D Exists | |
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| Send notices to | (None) |
draft-yoon-ippm-collection-interval-capabilities-00
IPPM Working Group B. Y. Yoon
Internet-Draft ETRI
Intended status: Standards Track Y. You
Expires: 7 January 2027 woori-net
6 July 2026
A YANG Data Model for Collection Interval Capabilities
draft-yoon-ippm-collection-interval-capabilities-00
Abstract
This document defines a YANG data model, "ietf-pm-interval-
capabilities", that enables a server to advertise which collection
intervals it can support. A client reads this capability information
before configuring performance measurements, so that it selects only
sampling and collection intervals that the server can honour. The
capabilities are advertised by augmenting the "ietf-system-
capabilities" module defined in [RFC9196], so that a client discovers
them at the same well-known location used for subscription and
notification capabilities. The model imports the "profile-names"
type from the companion collection measurement model defined in
[I-D.yoon-ippm-collection-measure] and mirrors its profile-and-
parameter structure, ensuring direct alignment between capability
discovery and measurement configuration. The model does not define
measurement data structures or any delivery mechanism; those are
defined in the companion document.
About This Document
This note is to be removed before publishing as an RFC.
The latest revision of this draft can be found at
https://binyeongyoon-ietf.github.io/ietf-pm-streaming/draft-yoon-
ippm-collection-interval-capabilities.html. Status information for
this document may be found at https://datatracker.ietf.org/doc/draft-
yoon-ippm-collection-interval-capabilities/.
Source for this draft and an issue tracker can be found at
https://github.com/binyeongyoon-ietf/ietf-pm-streaming.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
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Internet-Drafts are working documents of the Internet Engineering
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This Internet-Draft will expire on 7 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
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provided without warranty as described in the Revised BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3
1.2. Relationship to Companion Documents . . . . . . . . . . . 4
2. Motivation . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.1. Monitoring Objectives Require Different Intervals . . . . 6
2.2. Equipment Performance Determines Achievable Intervals . . 6
2.3. Multi-Vendor Interoperability . . . . . . . . . . . . . . 7
3. Structure and the Sampling/Measurement Relationship . . . . . 7
4. Capability Discovery and Configuration Workflow . . . . . . . 8
5. Interval Capabilities Example . . . . . . . . . . . . . . . . 10
6. Tree Diagram . . . . . . . . . . . . . . . . . . . . . . . . 12
7. YANG Module . . . . . . . . . . . . . . . . . . . . . . . . . 12
8. Manageability Considerations . . . . . . . . . . . . . . . . 18
9. Security Considerations . . . . . . . . . . . . . . . . . . . 18
10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 19
11. References . . . . . . . . . . . . . . . . . . . . . . . . . 19
11.1. Normative References . . . . . . . . . . . . . . . . . . 19
11.2. Informative References . . . . . . . . . . . . . . . . . 20
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 21
Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . 21
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Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 21
1. Introduction
The collection measurement data model defined in
[I-D.yoon-ippm-collection-measure] allows a client to configure
sampling and collection intervals for performance parameters within
named parameter profiles. The same parameter may require different
intervals depending on its type and monitoring objective, and
different network elements support different ranges and granularities
of intervals. Without a prior discovery step, a client risks
configuring interval values that the server cannot honour, leading to
configuration errors or suboptimal monitoring.
This document defines a YANG data model [RFC7950], "ietf-pm-interval-
capabilities", for advertising the collection collection interval
capabilities a server supports. A client reads this information from
the operational datastore before it configures measurements. The
model mirrors the profile-and-parameter structure of the companion
collection measurement model and reuses its "profile-names" type, so
that capability discovery aligns directly with measurement
configuration.
Rather than defining a separate top-level container, this module
augments the "system-capabilities" container of the "ietf-system-
capabilities" module defined in [RFC9196]. RFC 9196 provides a
placeholder structure that other modules augment to expose YANG-
related system capabilities; the companion module "ietf-notification-
capabilities" (Section 3 of [RFC9196]) uses the same anchor to
advertise subscription and notification capabilities. By augmenting
the same anchor, this module lets a NETCONF or RESTCONF client
discover the measurement interval capabilities and the subscription
capabilities through a single, standardised query, without prior
knowledge of this module's own layout.
This document does not define measurement data structures, collection
types, threshold events, or any delivery mechanism. All of those are
defined in the companion document [I-D.yoon-ippm-collection-measure].
1.1. Terminology
The terms "client", "server", "datastore", and "operational state"
are used as defined in [RFC6241] and [RFC8342].
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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. Relationship to Companion Documents
This document and [I-D.yoon-ippm-collection-measure] together provide
the functional coverage that was originally combined in a single
document, draft-yoon-ccamp-pm-streaming. The original document
defined both the PM collection data model and the interval capability
model in one place and focused on push-based streaming as the
delivery mechanism. The two documents have been separated to achieve
cleaner separation of concerns and to make the models delivery-
mechanism neutral.
The functional division is as follows.
[I-D.yoon-ippm-collection-measure] defines "ietf-pm-collection",
which covers:
* Parameter profiles and PM parameter groupings
* Three collection types: Counts, Snapshot, and Tidemarks (per ITU-T
G.7710 [G7710])
* Configurable sampling and collection intervals
* Threshold event notifications (periodic and non-periodic)
* Data structures accessible via pull-based retrieval (NETCONF,
RESTCONF) or push-based subscription (YANG-Push)
This document defines "ietf-pm-interval-capabilities", which covers:
* Read-only advertisement of the sampling and collection interval
ranges, units, defaults, and granularity that a server supports
* Hierarchical alignment with the companion model's profile-and-
parameter structure
* Capability discovery prior to measurement configuration
The separation of concerns is:
* "What data is collected and how it is structured" is in
[I-D.yoon-ippm-collection-measure].
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* "Which interval configurations the server can support" is in this
document.
Figure 1 illustrates the relationship between the two YANG modules.
+------------------------------------------+
| ietf-pm-interval-capabilities |
| (this document) |
| |
| pm-interval-capabilities |
| parameter-profile [profile-names] -+ |
| pm-parameter | |
| interval-relationships | |
| sampling-interval | |
| collection-interval | |
+------------------------------|----------+
| imports profile-names
v
+------------------------------------------+
| ietf-pm-collection |
| (draft-yoon-ippm-collection-measure-00) |
| |
| pm-periodic-collection |
| parameter-profile [profile-names] |
| pm-parameter |
| sampling-interval |
| collection-interval |
| collection-types |
| counts / snapshot / |
| tidemarks |
+------------------------------------------+
Figure 1: Relationship between ietf-pm-interval-capabilities and
ietf-pm- collection
2. Motivation
ITU-T G.7710 [G7710] does not include a clause that mandates a
capability-discovery mechanism for configurable measurement timing
parameters. However, because sampling and collection intervals are
configurable, a client needs to know in advance which intervals a
given server can support, so that requests can be built without
violating implementation constraints. This module provides that
advertisement.
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2.1. Monitoring Objectives Require Different Intervals
The same PM parameter may need to be collected simultaneously at
multiple sampling and collection interval combinations, each serving
a distinct operational objective. As illustrated by the use cases in
[I-D.yoon-ippm-collection-measure], Errored Seconds (ES) sampled
every second may be aggregated over a 1-minute interval for rapid
fault detection in a Network Operations Center (NOC), over a
15-minute interval for routine maintenance monitoring aligned with
ITU-T G.7710 [G7710], and over a 24-hour interval for daily QoS
reporting -- all three objectives active concurrently on the same
parameter. Similarly, latency parameters may be sampled at sub-
second granularity with short collection intervals for digital twin
synchronization, or at longer intervals for AI/ML model training.
A client wishing to configure all of these combinations for all
parameters in a profile must first verify that the target server
supports every required interval. Without a capability discovery
step, the client has no way to know whether a desired combination is
valid on the specific server, and may submit configurations that the
server silently truncates, rejects, or rounds to the nearest
supported value.
2.2. Equipment Performance Determines Achievable Intervals
Beyond monitoring objective, the processing capacity of the network
element itself directly determines which interval configurations are
feasible for a given parameter. Network elements vary significantly
in their measurement engines and hardware resources.
High-performance network elements with dedicated measurement
processors can support short minimum sampling intervals and fine-
grained collection interval steps, enabling high-resolution
monitoring for demanding use cases such as real-time fault detection,
network digital twins, and AI-driven analytics. For example, such a
device may support a 100-millisecond sampling interval for ES, with
collection intervals as short as 1 minute and a 5-second granularity
step.
Lower-specification network elements, constrained by processing
resources or hardware architecture, may support only longer minimum
intervals and coarser granularity steps. The same ES parameter on
such a device might have a minimum sampling interval of 1 second and
a minimum collection interval of 15 minutes, adequate for traditional
operations and maintenance monitoring but insufficient for sub-minute
analytics.
Table 1 shows an example comparison for the ES parameter.
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+===================+===============+=============+=============+
| Equipment class | Min. sampling | Min. | Granularity |
| | | measurement | |
+===================+===============+=============+=============+
| High-performance | 100 ms | 1 min | 5 s |
+-------------------+---------------+-------------+-------------+
| Standard | 1 s | 1 min | 1 min |
+-------------------+---------------+-------------+-------------+
| Low-specification | 1 s | 15 min | 15 min |
+-------------------+---------------+-------------+-------------+
Table 1: Example interval capabilities by equipment class (ES
parameter)
A client operating across a heterogeneous network cannot assume a
uniform interval floor and must discover the capabilities of each
network element individually. The interval capability model enables
a client to select the highest-resolution intervals a given server
supports for each operational objective, rather than applying a
conservative lowest-common-denominator configuration across all
devices.
2.3. Multi-Vendor Interoperability
Equipment from different vendors supports different ranges and
granularities of intervals, and may impose implementation-specific
constraints on the relationship between sampling and collection
intervals. In multi-vendor networks, clients must adapt to the
capabilities of each element. Without a discovery mechanism, clients
risk configuration failures, suboptimal monitoring, or system
instability. A standardised capability model addresses these
challenges and enables interoperability across diverse network
environments.
3. Structure and the Sampling/Measurement Relationship
The module follows a hierarchical structure that mirrors the
measurement configuration model defined in
[I-D.yoon-ippm-collection-measure], ensuring consistency between
capability discovery and actual configuration. It has three levels:
parameter profiles (collections of related parameters such as "itu-
transport-maintenance-15min"), PM parameters (individual parameters
such as ES, SES, BBE), and interval capabilities (supported sampling
and collection intervals for each parameter).
The model defines a key relationship: a collection interval MUST be a
multiple of its corresponding sampling interval. This ensures that
aggregation periods align with the data collection frequency. For
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example, if a server supports a 5-second sampling interval, valid
collection intervals are 5s, 10s, 15s, 30s, 60s, and so on. The
relationship is expressed structurally by nesting collection
intervals within their corresponding sampling interval entry.
For each interval, the model advertises:
* min-value: minimum supported numeric value
* max-value: maximum supported numeric value
* units: list of supported time units (e.g., second, minute)
* default-value: recommended default numeric value
* default-unit: recommended default time unit
* granularity: step size; valid values must be multiples of this
Once a client knows the supported intervals, it can pair a single
supported sampling interval with several supported collection
intervals to serve different operational purposes for the same
parameter. The "Use Cases" section of
[I-D.yoon-ippm-collection-measure] gives concrete examples of such
combinations, which motivate the ranges and granularities a server
advertises here.
4. Capability Discovery and Configuration Workflow
A client performs the following three steps to configure and access
collection measurements correctly. Steps 2 and 3 use the companion
model defined in [I-D.yoon-ippm-collection-measure]; Step 1 uses the
model defined in this document.
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+-----------+ +-----------+
| Client | | Server |
| (NMS/Ctrl)| | (NE) |
+-----+-----+ +-----+-----+
| |
| Step 1: Discover intervals |
| [ietf-pm-interval-capabilities] |
|---NETCONF get-data--------------> |
|<--pm-interval-capabilities-------- |
| |
| Step 2: Configure measurement |
| [ietf-pm-collection] |
|---NETCONF edit-config-----------> |
|<--OK------------------------------ |
| |
| Step 3: Access data |
| [ietf-pm-collection] |
| |
| Option A: Pull (polling) |
|---NETCONF get-data--------------> |
|<--collection-value--------------- |
| |
| Option B: Push (YANG-Push) |
|---establish-subscription--------> |
|<--periodic-notifications---------- |
| |
Figure 2: Combined Capability Discovery and Data Access Workflow
*Step 1 -- Discover interval capabilities (this document).* On
session establishment, the server's YANG Library [RFC8525] and
capability information indicate whether "ietf-pm-collection" and
"ietf-pm-interval-capabilities" are both supported. The client
queries the "pm-interval-capabilities" container, which this module
augments into the "system-capabilities" container of "ietf-system-
capabilities" [RFC9196]. Because that container is "config false",
the augmented nodes inherit "config false" and reside in the
operational datastore per the Network Management Datastore
Architecture (NMDA) [RFC8342]. Querying the same anchor also returns
any subscription and notification capabilities advertised there by
"ietf-notification-capabilities" (Section 3 of [RFC9196]). From it,
the client retrieves the supported sampling and collection intervals
for each parameter and profile, including the minimum and maximum
values, allowed units, and granularity. This runtime exposure
follows the model described in [RFC9196] for advertising capabilities
in operational state. The same information MAY also be published as
static instance data using the format defined in [RFC9195]. The
interval ranges advertised here correspond to the Measurement Timing
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aspect of the Performance Metric Specification described in
Section 5.4.2 of [RFC6390]; this document provides the runtime
discovery of those timing constraints, which the companion model
[I-D.yoon-ippm-collection-measure] then applies when measurements are
configured.
*Step 2 -- Configure measurements (companion document).* The client
configures the "pm-periodic-collection" container defined in "ietf-
pm-collection" [I-D.yoon-ippm-collection-measure], selecting only
sampling and collection interval values that Step 1 confirmed the
server supports. This avoids configuration errors such as an
unsupported interval being rejected during collection setup or
subscription establishment.
*Step 3 -- Access data (companion document).* The client accesses the
collected PM data using either pull-based retrieval or push-based
subscription, both supported by "ietf-pm- collection". For pull-
based access, the client issues NETCONF "get-data" or RESTCONF GET
operations against the operational datastore to read current
measurement values. For push-based access, the client establishes a
YANG-Push subscription per [RFC8639], [RFC8641], [RFC8640] to receive
periodic or threshold-triggered notifications.
5. Interval Capabilities Example
Figure 3 shows a NETCONF <get> request that retrieves the interval
capabilities for the ES parameter in the "itu-transport-maintenance-
15min" profile.
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<rpc xmlns="urn:ietf:params:xml:ns:netconf:base:1.0"
xmlns:sysc=
"urn:ietf:params:xml:ns:yang:ietf-system-capabilities"
xmlns:ipc=
"urn:ietf:params:xml:ns:yang:ietf-pm-interval-capabilities"
message-id="301">
<get>
<filter>
<sysc:system-capabilities>
<ipc:pm-interval-capabilities>
<parameter-profile>
<name>itu-transport-maintenance-15min</name>
<pm-parameter>
<name>es</name>
<interval-relationships>
<sampling-interval>
<id>1s</id>
<min-value>1</min-value>
<max-value>1</max-value>
<units>second</units>
<default-value>1</default-value>
<default-unit>second</default-unit>
<granularity>1</granularity>
<collection-interval>
<id>collection-range</id>
<min-value>5</min-value>
<max-value>1440</max-value>
<units>minute</units>
<default-value>15</default-value>
<default-unit>minute</default-unit>
<granularity>5</granularity>
</collection-interval>
</sampling-interval>
</interval-relationships>
</pm-parameter>
</parameter-profile>
</ipc:pm-interval-capabilities>
</sysc:system-capabilities>
</filter>
</get>
</rpc>
Figure 3: Interval Capabilities Discovery Request Example
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The response indicates that the server supports 1-second sampling and
a collection interval range of 5 to 1440 minutes with 5-minute
granularity, with a default of 15 minutes. Using this information,
the client can configure the ES parameter in "ietf-pm-collection"
with any collection interval that is a multiple of 5 within the range
5 to 1440 minutes, knowing the server will accept the configuration.
6. Tree Diagram
The following tree diagram, using the notation defined in [RFC8340],
shows the structure of the "ietf-pm-interval-capabilities" module.
module: ietf-pm-interval-capabilities
augment /sysc:system-capabilities:
+--ro pm-interval-capabilities
+--ro parameter-profile* [name]
+--ro name pm-coll:profile-names
+--ro pm-parameter* [name]
+--ro name string
+--ro interval-relationships
+--ro sampling-interval* [id]
+--ro id string
+--ro min-value? uint32
+--ro max-value? uint32
+--ro units* interval-unit
+--ro default-value? uint32
+--ro default-unit? interval-unit
+--ro granularity? uint32
+--ro collection-interval* [id]
+--ro id string
+--ro min-value? uint32
+--ro max-value? uint32
+--ro units* interval-unit
+--ro default-value? uint32
+--ro default-unit? interval-unit
+--ro granularity? uint32
Figure 4: Tree Diagram of ietf-pm-interval-capabilities
7. YANG Module
<CODE BEGINS> file "ietf-pm-interval-capabilities@2026-06-11.yang"
module ietf-pm-interval-capabilities {
yang-version 1.1;
namespace
"urn:ietf:params:xml:ns:yang:ietf-pm-interval-capabilities";
prefix ipc;
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import ietf-pm-collection {
prefix pm-coll;
reference
"RFC XXXX: A YANG Data Model for Collection Measurement";
}
import ietf-system-capabilities {
prefix sysc;
reference
"RFC 9196: YANG Modules Describing Capabilities for
Systems and Datastore Update Notifications";
}
organization
"IETF IP Performance Metrics (ippm) Working Group";
contact
"WG Web: <https://datatracker.ietf.org/wg/ippm/>
Editor: Bin Yeong Yoon <mailto:byyun@etri.re.kr>";
description
"This YANG module defines a data model for advertising
performance management (PM) collection interval capabilities
in network equipment. The module enables clients to discover
which sampling and collection intervals a server supports
for different performance parameters within various parameter
profiles, before configuring collection measurements.
This module provides hierarchical interval capability
discovery where collection intervals must be multiples of
their corresponding sampling intervals, and each parameter
can have different interval capabilities within each
parameter profile.
This module imports the profile-names type from
ietf-pm-collection and mirrors its profile-and-parameter
structure. It does not define measurement data structures,
collection types, or any delivery mechanism; those are
defined in ietf-pm-collection.
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.
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
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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
(https://www.rfc-editor.org/info/rfcXXXX); see the RFC itself
for full legal notices.";
revision 2026-06-11 {
description
"Initial revision as standalone interval capability module,
separated from the combined PM streaming document and
updated to import ietf-pm-collection. The interval
capabilities are advertised by augmenting the
system-capabilities container defined in RFC 9196.";
reference
"RFC XXXX: A YANG Data Model for Collection
Interval Capabilities";
}
/*
* TYPEDEFs
*/
typedef interval-unit {
type enumeration {
enum millisecond {
description "Time interval in milliseconds.";
}
enum second {
description "Time interval in seconds.";
}
enum minute {
description "Time interval in minutes.";
}
enum hour {
description "Time interval in hours.";
}
enum day {
description "Time interval in days.";
}
}
description "Supported units for expressing time intervals.";
}
/*
* GROUPINGS
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*/
grouping interval-constraints {
description
"Capability constraints for a single interval type,
covering the supported range, units, default, and
granularity. Used for both sampling intervals and
collection intervals.";
leaf min-value {
type uint32;
description
"Minimum supported value for this interval.";
}
leaf max-value {
type uint32;
description
"Maximum supported value for this interval.";
}
leaf-list units {
type interval-unit;
description
"List of supported time units for this interval.";
}
leaf default-value {
type uint32;
description
"Default value recommended for this interval.";
}
leaf default-unit {
type interval-unit;
description
"Default unit recommended for this interval.";
}
leaf granularity {
type uint32;
description
"Granularity step for interval values. Only values
that are multiples of this granularity are supported.
For example, if granularity is 5, valid values are
5, 10, 15, 20, and so on.";
}
}
grouping parameter-interval-capabilities {
description
"Interval capabilities for a single PM parameter within
a profile. The structure nests collection intervals
within their corresponding sampling interval, reflecting
the constraint that collection intervals must be
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multiples of their sampling interval.";
leaf name {
type string;
description
"Name of the performance parameter (e.g., es, ses,
bbe). This value corresponds to the pm-parameter
name leaf in ietf-pm-collection.";
}
container interval-relationships {
description
"Hierarchical relationships between sampling and
collection intervals for this parameter.
Collection intervals MUST be multiples of their
corresponding sampling intervals.";
list sampling-interval {
key "id";
description
"List of supported sampling intervals and their
compatible collection intervals.";
leaf id {
type string;
description
"Unique identifier for this sampling interval
capability entry.";
}
uses interval-constraints;
list collection-interval {
key "id";
description
"List of supported collection intervals for
this sampling interval.";
leaf id {
type string;
description
"Unique identifier for this collection
interval capability entry.";
}
uses interval-constraints;
}
}
}
}
grouping profile-parameter-capabilities {
description
"Interval capabilities for all PM parameters within a
single parameter profile.";
leaf name {
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type pm-coll:profile-names;
description
"Name of the parameter profile. This value
corresponds to the parameter-profile name leaf in
ietf-pm-collection (e.g.,
itu-transport-maintenance-15min).";
}
list pm-parameter {
key "name";
description
"List of PM parameters and their interval capabilities
within this profile.";
uses parameter-interval-capabilities;
}
}
/*
* AUGMENTATION OF ietf-system-capabilities (RFC 9196)
*
* The interval capabilities are advertised by augmenting the
* "system-capabilities" container defined in RFC 9196. This
* places the PM measurement interval capabilities at the same
* well-known location at which a NETCONF/RESTCONF client
* discovers subscription and notification capabilities
* (ietf-notification-capabilities, RFC 9196 Section 3), so that
* both can be retrieved in a single, standardised query. The
* "pm-interval-capabilities" wrapper container cleanly separates
* this capability group from other capabilities augmented into
* the same anchor. All augmented nodes inherit "config false"
* from sysc:system-capabilities and therefore reside in the
* operational datastore.
*/
augment "/sysc:system-capabilities" {
description
"Augments the system capabilities with PM collection
interval capabilities, advertising the sampling and
collection intervals that this server supports, organised
by parameter profile and PM parameter.";
container pm-interval-capabilities {
description
"Read-only advertisement of the sampling and collection
interval capabilities of this server, organised by
parameter profile and PM parameter. A client reads this
container to determine which interval values are valid
before configuring measurements in ietf-pm-collection.";
list parameter-profile {
key "name";
description
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"List of parameter profiles and their per-parameter
interval capabilities.";
uses profile-parameter-capabilities;
}
}
}
}
<CODE ENDS>
8. Manageability Considerations
A server SHOULD ensure that the capabilities advertised in "pm-
interval-capabilities" remain consistent with its actual ability to
honour interval configurations in "ietf-pm-collection". If a
server's resources change dynamically (e.g., due to load), it SHOULD
update the operational datastore accordingly, and clients that have
already configured measurements using previously advertised values
SHOULD be notified through standard NETCONF or YANG-Push mechanisms.
Operators SHOULD verify that the interval values configured in "ietf-
pm-collection" fall within the ranges advertised in this module
before deploying measurement configurations in production.
9. Security Considerations
The YANG module defined in this document defines data nodes that are
designed to be accessed via network management protocols such as
NETCONF [RFC6241] or RESTCONF. The module augments the "system-
capabilities" container of "ietf-system-capabilities" [RFC9196],
which is "config false"; all nodes added by this module therefore
inherit "config false" and reside in the operational datastore.
Following the guidance in [RFC9196], this section documents the
security considerations of the augmented nodes.
The lowest NETCONF layer is the secure transport layer, and the
mandatory-to-implement secure transport is Secure Shell (SSH). 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.
Although all nodes are read-only, the capability information they
expose can reveal vendor-specific implementation details about the
equipment, such as supported interval ranges and granularities.
Operators SHOULD restrict read access to authorised management
clients to prevent unintended disclosure of device implementation
characteristics.
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10. IANA Considerations
This document requests IANA to register the following URI in the "ns"
subregistry within the "IETF XML Registry" [RFC3688]:
URI: urn:ietf:params:xml:ns:yang:ietf-pm-interval-capabilities
Registrant Contact: The IESG. XML: N/A; the requested URI is an XML
namespace.
This document requests IANA to register the following YANG module in
the "YANG Module Names" registry [RFC6020]:
Name: ietf-pm-interval-capabilities Namespace:
urn:ietf:params:xml:ns:yang:ietf-pm-interval-capabilities Prefix: ipc
Reference: RFC XXXX
11. References
11.1. Normative References
[G7710] ITU-T, "Common Equipment Management Function
Requirements", ITU-T Recommendation G.7710, November 2025,
<https://www.itu.int/rec/T-REC-G.7710>.
[I-D.yoon-ippm-collection-measure]
Yoon, B. Y., "A YANG Data Model for Collection
Measurement", Work in Progress, Internet-Draft, draft-
yoon-ippm-collection-measure-00, 2026,
<https://datatracker.ietf.org/doc/html/draft-yoon-ippm-
collection-measure-00>.
[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>.
[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>.
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[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>.
[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>.
[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>.
[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>.
[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/rfc/rfc8342>.
[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/rfc/rfc8525>.
[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/rfc/rfc8639>.
[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/rfc/rfc8640>.
[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/rfc/rfc8641>.
[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/rfc/rfc9196>.
11.2. Informative References
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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/rfc/rfc3688>.
[RFC6390] Clark, A. and B. Claise, "Guidelines for Considering New
Performance Metric Development", BCP 170, RFC 6390,
DOI 10.17487/RFC6390, October 2011,
<https://www.rfc-editor.org/rfc/rfc6390>.
[RFC9195] Lengyel, B. and B. Claise, "A File Format for YANG
Instance Data", RFC 9195, DOI 10.17487/RFC9195, February
2022, <https://www.rfc-editor.org/rfc/rfc9195>.
Acknowledgments
The interval capability model in this document is derived from the PM
interval capabilities work originally defined in draft-yoon-ccamp-pm-
streaming, and has been separated into this standalone document to
complement the collection measurement model in draft-yoon-ippm-
collection-measure.
Contributors
Kwangkoog Lee
KT
Email: kwangkoog.lee@kt.com
Jongyoon Shin
SK Telecom
Email: jongyoon.shin@sk.com
Sungyong Nam
LGU+
Email: sy.nam@lguplus.co.kr
Authors' Addresses
Bin Yeong Yoon
ETRI
Email: byyun@etri.re.kr
Youngkil You
woori-net
Email: young@woori-net.com
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