NETMOD Working Group Q. Wu
Internet-Draft Huawei
Intended status: Standards Track B. Claise
Expires: January 9, 2021 Cisco
L. Geng
Z. Du
China Mobile
July 8, 2020
Telemetry Data Self Explanation Tags
draft-tao-netmod-yang-node-tags-03
Abstract
This document defines a method to tag data node associated with
telemetry data in YANG Modules. This YANG data node tagging method
can be used to provide input, instruction, indication to selection
filter and filter queries of operational state on a server during a
"pub/sub" service for YANG datastore updates and provide multiple
dimensional network visibility analysis when the state of all
subscriptions of a particular Subscriber to be fetched is huge, so
that the amount of data to be streamed out to the destination can be
greatly reduced and only targeted to the characteristics data.
An extension statement to be used to indicate YANG data node self
explanation tags that SHOULD be added by the module implementation
automatically (i.e., outside of configuration).
A YANG module [RFC7950] is defined, which augments Module tag model
and provides a list of data node entries to allow for adding or
removing of data node self explanation tags as well as viewing the
set of self explanation tags associated with a YANG module.
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."
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This Internet-Draft will expire on January 9, 2021.
Copyright Notice
Copyright (c) 2020 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 Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Data Node tags Use Cases . . . . . . . . . . . . . . . . 4
1.1.1. Multiple Dimensional Performance Measurement
Information Tagging . . . . . . . . . . . . . . . . . 4
1.1.2. Correlated Information Tagging . . . . . . . . . . . 7
1.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 8
2. Data Node Tag Values . . . . . . . . . . . . . . . . . . . . 8
2.1. IETF Tags Prefix . . . . . . . . . . . . . . . . . . . . 8
2.2. Vendor Tags Prefix . . . . . . . . . . . . . . . . . . . 8
2.3. User Tags Prefix . . . . . . . . . . . . . . . . . . . . 8
2.4. Reserved Tags Prefix . . . . . . . . . . . . . . . . . . 8
3. Data Node Tag Management . . . . . . . . . . . . . . . . . . 9
3.1. Module Design Tagging . . . . . . . . . . . . . . . . . . 9
3.2. Implementation Tagging . . . . . . . . . . . . . . . . . 9
3.3. User Tagging . . . . . . . . . . . . . . . . . . . . . . 9
4. Tags Module Structure . . . . . . . . . . . . . . . . . . . . 9
4.1. Tags Module Tree . . . . . . . . . . . . . . . . . . . . 9
5. YANG Module . . . . . . . . . . . . . . . . . . . . . . . . . 10
6. Guidelines to Model Writers . . . . . . . . . . . . . . . . . 18
6.1. Define Standard Tags . . . . . . . . . . . . . . . . . . 18
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 19
7.1. YANG Data Node Tag Prefixes Registry . . . . . . . . . . 19
7.2. IETF YANG Data Node Tags Registry . . . . . . . . . . . . 20
7.3. Updates to the IETF XML Registry . . . . . . . . . . . . 25
7.4. Updates to the YANG Module Names Registry . . . . . . . . 25
8. Security Considerations . . . . . . . . . . . . . . . . . . . 25
9. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 26
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 26
10.1. Normative References . . . . . . . . . . . . . . . . . . 26
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10.2. Informative References . . . . . . . . . . . . . . . . . 26
Appendix A. Targeted data object subscription example . . . . . 27
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 29
1. Introduction
As described [I.D-ietf-netmod-module-tags], the use of tags for
classification and organization is fairly ubiquitous not only within
IETF protocols, but in the internet itself (e.g., "#hashtags"). A
module tag defined in [I.D-ietf-netmod-module-tags] is a string
associated only with a module name at module level.
At the time of writing this document (2020), there are many data
models that have been specified or are being specified by various
different SDOs and Open Souce community. They cover many of the
networking protocols and techniques. However data objects defined by
these technology specific data models might represent a portion of
fault, configuration, accounting, performance, security management
categories information (e.g., performance metric specific data object
type) in various different ways, lack consistent classification
criteria and representation granularity,e.g., sensor data in hardware
model is defined with fine granularity with value scale and value
precision while interface model only provides statistics data for
specific interface type.
This document defines data node self explanation tags and associates
them with data nodes within YANG module, which
o Provide dictionary meaning for specific targeted data nodes;
o Indicate relationship between data nodes within the same YANG
module or from different YANG modules;
o Identify key performance metric scale, precision, statistics
operation;
o Identify specific service or feature, data source.
The data node self explanation tags can be used by the client to
provide input, instruction, indication to selection filter and filter
queries of configuration or operational state on a server based on
these data node tags,.e.g.,return specific object type of operational
state related to system-management. NETCONF clients can discover
data objects with data node self explanation tags supported by a
NETCONF server via <get-schema> operation. The data node self
explanation tag capability can also be advertised via capability
notification Model [I-D.netconf-notification-capabilities] by the
NETCONF server or some place where offline document are kept. These
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self explanation tags may be registered as well as assigned during
the module definition; assigned by implementations; or dynamically
defined and set by users.
This document defines a YANG module [RFC7950] which augments module
tag model and provides a list of data node entries to allow for
adding or removing of self explanation tags as well as viewing the
set of self explanation tags associated with a data node within YANG
modules.
This document defines an extension statement to be used to indicate
self explanation tags that SHOULD be added by the module
implementation automatically (i.e., outside of configuration).
The YANG data model in this document conforms to the Network
Management Datastore Architecture defined in [RFC8342].
1.1. Data Node tags Use Cases
The following is a list of already implemented and potential use
cases.
1.1.1. Multiple Dimensional Performance Measurement Information Tagging
Data node tags can be used to express multiple dimensional
performance metric and properties associated with YANG data nodes or
data objects modelled with YANG (See Figure 1).
----- -----
// \\ // \\
| Property+------+ +-------+ Property|
\\ A // | | \\ B //
-----+ +--V----------------V---+ -----
| YANG Data Node |
| /Data Object |
/---\ +--^----------------^---+ /---\
/ \ | | / \
|Metric +-------+ +--------|Metric |
\ A / +-------------+ \ B /
\-+-/ | | \-+-/
| | Metric Group| |
-------------| |---------------
+-------------+
Figure 1
The use of data node tags would be to help filter different discrete
categories of YANG data nodes across YANG modules supported by a
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device. If data nodes across YANG modules are suitably tagged and
learnt by the client from a live server, then an XPath query can be
used by the client to list all related data nodes supported by a
device with the same characteristics. Data node tags can also be
used to help coordination when clients are interacting with various
different devices with the same categories of YANG data node across
different YANG modules. For example, one management client could
mark some specific data node across modules implemented in various
different devices with the same metric group tag, so consistent
representation and reporting can be provided for YANG data nodes
belonging to the same metric group (see Figure 2).
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+-----------+---------------+-----------+-----------------------+
| Object | Property | Metric | Metric Module |
| Name | Name | Group | Name |
| | | | |
|tunnel-svc | name | - | - tunnel |
| | | | |
|tunnel-svc | create-time | - | - tunnel |
| | | | |
|tunnel-svc | modified-time | - | - |
| | | | |
|tunnel-svc | - |lsp-ping-pm| avg-latency tunnel-pm|
| | | | |
|tunnel-svc | - |lsp-ping-pm| packet-loss tunnel-pm|
| | | | |
|tunnel-svc | - |lsp-ping-pm| min-latency tunnel-pm|
| | | | |
|tunnel-svc | - |lsp-ping-pm| max-latency tunnel-pm|
| | | |transmitted |
|tunnel-svc | - |lsp-ping-pm| -packet tunnel-pm|
+-----------+---------------+-----------+-----------------------+
+---------------------------------------------------------+
| Metric Metric Metric Metric Metric |
| Group Name Precision Scale Unit |
| |
| lsp-ping-pm avg- 1 1 ms |
| latency |
| |
| lsp-ping-pm packet- 1 1 percentile |
| loss |
| |
| |
| lsp-ping-pm min- 1 1 ms |
| latency |
| |
| |
| lsp-ping-pm max- 1 1 ms |
| latency |
| |
| |
| lsp-ping-pm transmitted 1 1 |
+---------------------------------------------------------+
Figure 2
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1.1.2. Correlated Information Tagging
Another example is the management client could mark some data node
across different level of YANG modules implemented in the device, the
management system with the same service tag (e.g., L3VPN Service), so
root cause can be identified efficiently during service-level
agreements and performance monitoring or network failure
troubleshooting.
+--------------+
| Parent object|
+-------^------+
|
----- +-----+-----+ -----
// \\ |Service Tag| // \\
| Property+------+ ++--------+-+ +-------+ Property|
\\ A // | | | | \\ B //
-----+ +--V---V-+ +-V---V--+ -----
| Child | | Child |
|ObjectA | |ObjectB |
/---\ +--^-----+ +-----^--+ /---\
/ \ | | / \
|Metric +-------+ +--------|Metric |
\ A / \ B /
\---/ \---/
+-----------------------------------------------------------+
| Service Metric Metric Module Level |
| Tag Group Name |
| |
| L3VPN L3VPN maximum L3VPN Service |
| -routes |
| |
| L3VPN OSPF-Process total-active OSPF Device |
| routes |
| |
| total-active |
| L3VPN RIP-Process routes RIP Device |
| |
| total-active |
| L3VPN BGP-Process routes BGP Device |
| |
+-----------------------------------------------------------+
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1.2. 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.
2. Data Node Tag Values
All data node tags SHOULD begin with a prefix indicating who owns
their definition. An IANA registry (Section 7.1) is used to support
registering data node tag prefixes. Currently 3 prefixes are
defined.
No further structure is imposed by this document on the value
following the registered prefix, and the value can contain any YANG
type 'string' characters except carriage-returns, newlines and tabs.
Therefore, designers, implementers, and users are free to add or not
add any structure they may require to their own tag values.
2.1. IETF Tags Prefix
An IETF tag is a data node tag that has the prefix "ietf:". All IETF
data node tags are registered with IANA in a registry defined later
in this document (Section 7.2).
2.2. Vendor Tags Prefix
A vendor tag is a tag that has the prefix "vendor:". These tags are
defined by the vendor that implements the module, and are not
registered; however, it is RECOMMENDED that the vendor include extra
identification in the tag to avoid collisions such as using the
enterpise or organization name following the "vendor:" prefix (e.g.,
vendor:vendor-defined-classifier).
2.3. User Tags Prefix
A user tag is any tag that has the prefix "user:". These tags are
defined by the user/administrator and are not meant to be registered.
Users are not required to use the "user:" prefix; however, doing so
is RECOMMENDED as it helps avoid prefix collisions.
2.4. Reserved Tags Prefix
Any tag not starting with the prefix "ietf:", "vendor:" or "user:" is
reserved for future use. These tag values are not invalid, but
simply reserved in the context of specifications (e.g., RFCs).
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3. Data Node Tag Management
Tags can become associated with a data node within YANG module in a
number of ways. Tags may be defined and associated at module design
time, at implementation time without the need of live server, or via
user administrative control . As the main consumer of data node tags
are users, users may also remove any tag from a live server, no
matter how the tag became associated with a data node within a YANG
module.
3.1. Module Design Tagging
A data node definition MAY indicate a set of data node tags to be
added by the module implementer. These design time tags are
indicated using the node-tag extension statement.
If the data node is defined in an IETF standards track document, the
data node tags MUST be IETF Tags (2.1). Thus, new data node can
drive the addition of new IETF tags to the IANA registry defined in
Section 7.2, and the IANA registry can serve as a check against
duplication.
3.2. Implementation Tagging
An implementation MAY include additional tags associated with data
node within a YANG module. These tags SHOULD be IETF Tags (i.e.,
registered) or vendor specific tags.
3.3. User Tagging
Data node tags of any kind, with or without a prefix, can be assigned
and removed by the user from a live server using normal configuration
mechanisms. In order to remove a data node tag from the operational
datastore, the user adds a matching "masked-tag" entry for a given
data node within the ietf-data-node-tags Module.
4. Tags Module Structure
4.1. Tags Module Tree
The tree associated with the "ietf-data-node-tags" module follows.
The meaning of the symbols can be found in [RFC8340].
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module: ietf-data-node-tags
augment /tags:module-tags/tags:module:
+--rw self-explanation-node-tags
+--rw self-explanation-node* [node-name]
+--rw node-name nacm:node-instance-identifier
+--rw opm-tag tags:tag
+--rw metric-precision tags:tag
+--rw metric-scale tags:tag
+--rw operation-type tags:tag
+--rw service-tag* tags:tag
+--rw task-tag* tags:tag
+--rw multi-source-tag tags:tag
+--rw data-source tags:tag
5. YANG Module
<CODE BEGINS> file "ietf-self-explanation-node-tags@2019-05-03.yang"
module ietf-self-explanation-node-tags {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-self-explanation-node-tags";
prefix ntags;
import ietf-netconf-acm { prefix nacm; }
import ietf-module-tags { prefix tags; }
organization
"IETF NetMod Working Group (NetMod)";
contact
"WG Web: <https://tools.ietf.org/wg/netmod/>
WG List: <mailto:netmod@ietf.org>
Editor: Qin Wu <mailto:bill.wu@huawei.com>
Editor: Benoit Claise <mailto:bclaise@cisco.com>
Editor: Liang Geng <mailto:gengliang@chinamobile.com>
Editor: Zongpeng Du <mailto:duzongpeng@chinamobile.com>";
// RFC Ed.: replace XXXX with actual RFC number and
// remove this note.
description
"This module describes a mechanism associating self-explanation
tags with YANG data node within YANG modules. Tags may be IANA
assigned or privately defined.
Copyright (c) 2020 IETF Trust and the persons identified as
authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or
without modification, is permitted pursuant to, and subject to
the license terms contained in, the Simplified BSD License set
forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
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(https://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX
(https://tools.ietf.org/html/rfcXXXX); see the RFC itself for
full legal notices.";
// RFC Ed.: update the date below with the date of RFC publication
// and RFC number and remove this note.
revision 2019-05-03 {
description
"Initial revision.";
reference "RFC XXXX: YANG Data Node Tags";
}
typedef tag {
type string {
length "1..max";
pattern '[a-zA-Z_][a-zA-Z0-9\-_]*:[\S ]+';
}
description
"A tag value is composed of a standard prefix followed by any type
'string' value that does not include carriage return, newline or
tab characters.";
}
typedef metric-precision {
type int8 {
range "-8 .. 9";
}
description
"A node using this data type represents a sensor value
precision range.
A node of this type SHOULD be defined together with nodes of
type measurement-units and type measurement-scale. Together,
associated nodes of these three types are used to identify the
semantics of a node of type sensor-value.
If a node of this type contains a value in the range 1 to 9,
it represents the number of decimal places in the fractional
part of an associated sensor-value fixed-point number.
If a node of this type contains a value in the range -8 to -1,
it represents the number of accurate digits in the associated
sensor-value fixed-point number.
The value zero indicates the associated sensor-value node is
not a fixed-point number.
Server implementers must choose a value for the associated
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sensor-value-precision node so that the precision and accuracy
of the associated sensor-value node is correctly indicated.
For example, a component representing a temperature sensor
that can measure 0 to 100 degrees C in 0.1 degree
increments, +/- 0.05 degrees, would have a
sensor-value-precision value of '1', a sensor-value-scale
value of 'units', and a sensor-value ranging from '0' to
'1000'. The sensor-value would be interpreted as
'degrees C * 10'.";
reference
"RFC 3433: Entity Sensor Management Information Base -
EntitySensorPrecision";
}
typedef metric-scale {
type enumeration {
enum yocto {
value 1;
description
"Measurement scaling factor of 10^-24.";
}
enum zepto {
value 2;
description
"Measurement scaling factor of 10^-21.";
}
enum atto {
value 3;
description
"Measurement scaling factor of 10^-18.";
}
enum femto {
value 4;
description
"Measurement scaling factor of 10^-15.";
}
enum pico {
value 5;
description
"Measurement scaling factor of 10^-12.";
}
enum nano {
value 6;
description
"Measurement scaling factor of 10^-9.";
}
enum micro {
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value 7;
description
"Measurement scaling factor of 10^-6.";
}
enum milli {
value 8;
description
"Measurement scaling factor of 10^-3.";
}
enum units {
value 9;
description
"Measurement scaling factor of 10^0.";
}
enum kilo {
value 10;
description
"Measurement scaling factor of 10^3.";
}
enum mega {
value 11;
description
"Measurement scaling factor of 10^6.";
}
enum giga {
value 12;
description
"Measurement scaling factor of 10^9.";
}
enum tera {
value 13;
description
"Measurement scaling factor of 10^12.";
}
enum peta {
value 14;
description
"Measurement scaling factor of 10^15.";
}
enum exa {
value 15;
description
"Measurement scaling factor of 10^18.";
}
enum zetta {
value 16;
description
"Measurement scaling factor of 10^21.";
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}
enum yotta {
value 17;
description
"Measurement scaling factor of 10^24.";
}
}
description
"A node using this data type represents a data scaling factor,
represented with an International System of Units (SI) prefix.
The actual data units are determined by examining a node of
this type together with the associated sensor-value-type.
A node of this type SHOULD be defined together with nodes of
type sensor-value-type and type sensor-value-precision.
Together, associated nodes of these three types are used to
identify the semantics of a node of type sensor-value.";
reference
"RFC 3433: Entity Sensor Management Information Base -
EntitySensorDataScale";
}
identity metric-unit {
description
"Base identity for measurement unit.";
}
identity ac-volts {
base metric-unit;
description
"Identity for a measure of electric potential (alternating current).";
}
identity dc-volts {
base metric-unit;
description
"Identity for a measure of electric potential (direct current).";
}
identity amperes {
base metric-unit;
description
"Identity for a measure of electric current.";
}
identity power {
base metric-unit;
description
"Identity for a measure of power.";
}
identity hertz {
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base metric-unit;
description
"Identity for a measure of frequency.";
}
identity celsius {
base metric-unit;
description
"Identity for a measure of temperature.";
}
identity rpm {
base metric-unit;
description
"Identity for a measure of shaft revolutions per minute.";
}
extension opm-tag {
argument tag;
description
"The argument 'tag' is of type 'tag'. This extension statement
is used by module authors to indicate the opm tags that SHOULD be
added automatically by the system. As such the origin of the
value for the pre-defined tags should be set to 'system'
[RFC8342].";
}
extension metric-scale{
argument tag;
description
"The argument 'tag' is of type 'tag'.The metric-scale can be
used to provide an additional metric scale (e.g., Measurement
scaling factor of 10^0, 10^-3,10^3) information associated with
the performance metric data node tag.";
}
extension metric-precision {
argument tag;
description
"The argument 'tag' is of type 'tag'.The metric-precision can be
used to provide an additional metric precision (e.g., the range -8 to -1,
0, the range 1 to 9) information associated with the performance metric
data node tag.";
}
extension statistics-operation {
argument tag;
description
"The argument 'tag' is of type 'tag'.The statistics-operation can be
used to provide an additional statistics operation type(e.g., sum,
min, max,last) information associated with the performance metric
data node tag.";
}
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extension service-tag {
argument tag;
description
"The argument 'tag' is of type 'tag'.The service-tag can be
used to provide a service classification information (e.g., tunnel,
l3vpn,l2vpn) information associated with YANG data node.";
}
extension task-tag {
argument tag;
description
"The argument 'tag' is of type 'tag'.The task-tag can be
used to provide a task classification information (e.g., fault management,
performance measurement) information associated with YANG data node.";
}
extension data-source {
argument tag;
description
"The argument 'tag' is of type 'tag'.The data-source-type can be
used to provide an additional data source type (e.g., connectivity,
resource, hardware,qos,policy) information associated with
the performance metric data node tag.";
}
extension multi-source-tag {
argument tag;
description
"The argument 'tag' is of type 'tag'.The multi-source-tag can be
used to provide an additional multiple source aggregation
information associated with the performance metric data node
or interface related data node.";
}
augment "/tags:module-tags/tags:module" {
description
"Augment the Tags module with data node tag attributes";
container self-explanation-node-tags {
description
"Contains the list of data nodes and their associated tags";
list self-explanation-node {
key "node-name";
description
"A list of self-explanation nodes and their associated tags";
leaf node-name {
type nacm:node-instance-identifier;
mandatory true;
description
"The YANG data node name.";
}
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leaf opm-tag {
type tags:tag;
description
"Tags associated with the data node within YANG module. See
the IANA 'YANG Data Node Tag Prefixes' registry for reserved
prefixes and the IANA'IETF YANG Data Node Tags' registry for
IETF tags.
The 'operational' state [RFC8342] view of this list is
constructed using the following steps:
1) System tags (i.e., tags of 'system' origin) are added.
2) User configured tags (i.e., tags of 'intended' origin)
are added.
3) Any tag that is equal to a masked-tag is removed.";
}
leaf metric-precision {
type tags:tag;
description
"The numeric expression precision of performance
metric related data node.";
}
leaf metric-scale {
type tags:tag;
description
"The measurement scale of performance
metric related data node.";
}
leaf operation-type{
type tags:tag;
description
"Statistics operation of performance metric related
data node, e.g., average,min, max,sum, threshold.
If the operation type is threshold type, the corresponding
data object support threshold handling,e.g.,scan all interfaces
for a certain type every 5 seconds and check the counters or
status to cross threshold, return an array of interface entries
that match the search.If the operation type is average,min,max, sum,
it indicate the data object supports statistics operation, e.g.,
scan all interfaces for a certain type every 5 seconds up to 60 seconds,
only return min, average, max, sum value of specific data object rather than
the values that are current at the end of 60 seconds.";
}
leaf service-tag {
type tags:tag;
description
"The node-service-tag can be used to provide a service
classification information (e.g., tunnel, l3vpn,l2vpn)
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information associated with YANG data node.";
}
leaf task-tag {
type tags:tag;
description
"The node-task-tag can be used to provide a task
classification information (e.g., fault management,
performance measurement) information associated with
YANG data node.";
}
leaf multi-source-tag {
type tags:tag;
description
"The mulitple source tag can be used to identify multiple source
aggregation tye(e.g., line card,member link in an aggregated
Ethernet interface) related to performance metric related
data node or interface related to data node). Two source
aggregation source types are supported, one is aggregation
which groups data from two or multiple different data objects,
the other is membership which identitfy each data object(e.g.,
linecard, member link from multiple source aggregation.";
}
leaf data-source {
type tags:tag;
description
"The data source type (e.g., connectivity,resource, hardware
,qos,policy) associated with the performance metric data node
within YANG module.";
}
}
}
}
}
<CODE ENDS>
6. Guidelines to Model Writers
This section updates [RFC8407].
6.1. Define Standard Tags
A module MAY indicate, using node-tag extension statements, a set of
tags that are to be automatically associated with it (i.e., not added
through configuration).
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module example-module-A {
//...
import ietf-data-node-tags { prefix ntags; }
container top {
ntags:opm-tag "ietf:object-type";
list X {
leaf foo {
ntags:opm-tag "ietf:property";
}
}
container Y {
ntags:opm-tag "ietf:metric";
leaf bar {
ntags:statistics-operation "ietf:avg";
ntags:metric-scale "ietf:milli";
}
}
}
// ...
}
The module writer can use existing standard tags, or use new tags
defined in the model definition, as appropriate. For IETF
standardized modules new data node tags MUST be assigned in the IANA
registry defined below, see Section Section 7.2.
7. IANA Considerations
7.1. YANG Data Node Tag Prefixes Registry
IANA is asked to create a new registry "YANG Data Node Tag Prefixes"
grouped under a new "Protocol" category named "YANG Data Node Tag
Prefixes".
This registry allocates tag prefixes. All YANG data node tags SHOULD
begin with one of the prefixes in this registry.
Prefix entries in this registry should be short strings consisting of
lowercase ASCII alpha-numeric characters and a final ":" character.
The allocation policy for this registry is Specification Required
[RFC8126]. The Reference and Assignee values should be sufficient to
identify and contact the organization that has been allocated the
prefix.
The initial values for this registry are as follows.
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+----------+----------------------------------+-----------+----------+
| Prefix | Description | Reference | Assignee |
+----------+----------------------------------+-----------+----------+
| ietf: | IETF Tags allocated in the IANA | [This | IETF |
| | IETF YANG Data Node Tags registry| document] | |
| | | | |
|vendor: | Non-registered tags allocated by | [This | IETF |
| | the module implementer. | document] | |
| | | | |
| user: | Non-registered tags allocated by | [This | IETF |
| | and for the user. | document] | |
+----------+----------------------------------+-----------+----------+
Other standards organizations (SDOs) wishing to allocate their own
set of tags should allocate a prefix from this registry.
7.2. IETF YANG Data Node Tags Registry
IANA is asked to create four new registries "IETF YANG Data Node
Tags","IETF Metric Precision Tags","IETF Statistics Operation
Tags","Node Service Tag" grouped under a new "Protocol" category
"IETF YANG Data Node Tags". These four registries should be included
below "YANG Data Node Tag Prefixes" when listed on the same page.
Four registries allocate tags that have the registered prefix
"ietf:". New values should be well considered and not achievable
through a combination of already existing IETF tags.
The allocation policy for these four registries is IETF Review
[RFC8126].
The initial values for these eight registries are as follows.
+----------------------------+--------------------------+-----------+
| Data Node Tag | Description | Reference |
+----------------------------+--------------------------+-----------+
| | | |
| ietf:object-type | Relates to object type | [This |
| | (e.g., interfaces). | document] |
| | | |
| ietf:metric | Relates to performance | [This |
| | metric info | document] |
| | (e.g., ifstatistics). | |
| | | |
| ietf:metric-group | Represent metric group | [This |
| | (e.g., flow statistics). | document] |
| | | |
| ietf:property | Represents a object | [This |
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| | property | document] |
| | (e.g.,ifindex). | |
+----------------------------+--------------------------+-----------+
+----------------------------+--------------------------+-----------+
| Metric Precision | Description | Reference |
+----------------------------+--------------------------+-----------+
|ietf:minus-eight |Relates to metric precision [This |
| | of performance metric | document] |
| | | |
|ietf:minus-seven |Relates to metric precision [This |
| | of performance metric | document] |
| | | |
|ietf:minus-sixe |Relates to metric precision [This |
| | of performance metric | document] |
| | | |
|ietf:minus-five |Relates to metric precision [This |
| | of performance metric | document] |
| | | |
|ietf:minus-four |Relates to metric precision [This |
| | of performance metric | document] |
| | | |
|ietf:minus-three |Relates to metric precision [This |
| | of performance metric | document] |
| | | |
|ietf:minus-two |Relates to metric precision [This |
| | of performance metric | document] |
| | | |
|ietf:minus-one |Relates to metric precision [This |
| | of performance metric | document] |
| | | |
|ietf:zero |Relates to metric precision [This |
| | of performance metric | document] |
| | | |
|ietf:one |Relates to metric precision [This |
| | of performance metric | document] |
| | | |
|ietf:two |Relates to metric precision [This |
| | of performance metric | document] |
| | | |
|ietf:three |Relates to metric precision [This |
| | of performance metric | document] |
| | | |
|ietf:four | Relates to metric precision [This |
| | of performance metric | document] |
| | | |
|ietf:five | Relates to metric precision [This |
| | of performance metric | document] |
| | | |
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|ietf:six | Relates to metric precision [This |
| | of performance metric | document] |
| | | |
|ietf:seven | Relates to metric precision [This |
| | of performance metric | document] |
| | | |
|ietf:eight | Relates to metric precision [This |
| | of performance metric | document] |
| | | |
|ietf:nine | Relates to metric precision [This |
| | of performance metric | document] |
+----------------------------+--------------------------+-----------+
+----------------------------+--------------------------+-----------+
| Metric scale | Description | Reference |
+----------------------------+--------------------------+-----------+
|ietf:yocto | Relates to metric scale | [This |
| | of performance metric | document] |
| | | |
|ietf:zepto | Relates to metric scale | [This |
| | of performance metric | document] |
| | | |
|ietf:atto | Relates to metric scale | [This |
| | of performance metric | document] |
| | | |
|ietf: femto | Relates to metric scale | [This |
| | of performance metric | document] |
| | | |
|ietf: pico | Relates to metric scale | [This |
| | of performance metric | document] |
| | | |
|ietf: nano | Relates to metric scale | [This |
| | of performance metric | document] |
| | | |
|ietf: micro | Relates to metric scale | [This |
| | of performance metric | document] |
| | | |
|ietf: milli | Relates to metric scale | [This |
| | of performance metric | document] |
| | | |
|ietf: units | Relates to metric scale | [This |
| | of performance metric | document] |
| | | |
|ietf: kilo | Relates to metric scale | [This |
| | of performance metric | document] |
| | | |
|ietf: mega | Relates to metric scale | [This |
| | of performance metric | document] |
| | | |
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|ietf: giga | Relates to metric scale | [This |
| | of performance metric | document] |
| | | |
|ietf: tera | Relates to metric scale | [This |
| | of performance metric | document] |
| | | |
|ietf: peta | Relates to metric scale | [This |
| | of performance metric | document] |
| | | |
|ietf: exa | Relates to metric scale | [This |
| | of performance metric | document] |
| | | |
|ietf: zetta | Relates to metric scale | [This |
| | of performance metric | document] |
| | | |
|ietf: yotta | Relates to metric scale | [This |
| | of performance metric | document] |
+----------------------------+--------------------------+-----------+
+----------------------------+--------------------------+-----------+
| Operation Type Tag | Description | Reference |
+----------------------------+--------------------------+-----------+
|ietf:avg | Relates to statistics | [This |
| | operation(e.g.,average, | document] |
| | min, max, sum,etc) | |
|ietf:sum | Relates to statistics | [This |
| | operation(e.g.,average, | document] |
| | min, max, sum,etc) | |
|ietf:min | Relates to statistics | [This |
| | operation(e.g.,average, | document] |
| | min, max, sum,etc) | |
|ietf:max | Relates to statistics | [This |
| | operation(e.g.,average, | document] |
| | min, max, sum,etc) | |
|ietf:threshold | Relates to statistics | [This |
| | operation(e.g.,average, | document] |
| | min, max, threshold,etc) | |
+----------------------------+--------------------------+-----------+
+----------------------------+--------------------------+-----------+
| Parent Tag | Description | Reference |
+----------------------------+--------------------------+-----------+
|ietf:member |Relates to multiple source| [This |
| |aggregation type(e.g., | document] |
| |lag, linecard, sub inf) | |
| | | |
|ietf:agg |Relates to multiple source| [This |
| |aggregation type(e.g.,agg)| document] |
+----------------------------+--------------------------+-----------+
+----------------------------+--------------------------+-----------+
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| Data Source | Description | Reference |
+----------------------------+--------------------------+-----------+
| | | |
| ietf:service-flow | Relates to data source | [This |
| | type(e.g., microburst). | document] |
| | | |
| ietf:topo | Relates to data source | [This |
| | type(e.g., topology). | document] |
| | | |
| ietf:resource | Relates to data source | [This |
| | type info | document] |
| | (e.g., interface,queue). | |
| | | |
| ietf:policy | Relates to data source | [This |
| | type info | document] |
| |(e.g., acl, routing policy| |
| | | |
| ietf:hardware | Relates to data source | [This |
| | type | document] |
| | (e.g.,optical module). | |
+----------------------------+--------------------------+-----------+
+----------------------------+--------------------------+-----------+
| Service Tag | Description | Reference |
+----------------------------+--------------------------+-----------+
|ietf:l3vpn | Relates to service | [This |
| | offering(e.g.,l3vpn | document] |
| | l2vpn,tunnel,etc) | |
|ietf:l2vpn | Relates to service | [This |
| | offering(e.g.,l3vpn | document] |
| | l2vpn,tunnel,etc) | |
|ietf:te-tunnel | Relates to service | [This |
| | offering(e.g.,l3vpn | document] |
| | l2vpn,tunnel,etc) | |
+----------------------------+--------------------------+-----------+
+----------------------------+--------------------------+-----------+
| Task Tag | Description | Reference |
+----------------------------+--------------------------+-----------+
|ietf:vpn-diag | Relates to vpn serivce | [This |
| | diagonostic function | document] |
| | | |
|ietf:vpn-fullfilment | Relates to vpn service | [This |
| | fullfillment function | document] |
| | | |
|ietf:vpn-assurance | Relates to vpn service | [This |
| | assurance function | document] |
+----------------------------+--------------------------+-----------+
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7.3. Updates to the IETF XML Registry
This document registers a URI in the "IETF XML Registry" [RFC3688].
Following the format in [RFC3688], the following registration has
been made:
URI:
urn:ietf:params:xml:ns:yang:ietf-self-explaination-node-tags
Registrant Contact:
The IESG.
XML:
N/A; the requested URI is an XML namespace.
7.4. Updates to the YANG Module Names Registry
This document registers one YANG module in the "YANG Module Names"
registry [RFC6020]. Following the format in [RFC6020], the following
registration has been made:
name:
ietf-self-explaination-node-tags
namespace:
urn:ietf:params:xml:ns:yang:ietf-self-explaination-node-tags
prefix:
ntags
reference:
RFC XXXX (RFC Ed.: replace XXX with actual RFC number and remove
this note.)
8. Security Considerations
The YANG module defined in this memo is designed to be accessed via
the NETCONF protocol [RFC6241]. The lowest NETCONF layer is the
secure transport layer and the mandatory-to-implement secure
transport is SSH [RFC6242].
This document adds the ability to associate data node tag meta-data
with YANG modules. This document does not define any actions based
on these associations, and none are yet defined, and therefore it
does not by itself introduce any new security considerations.
Users of the data node tag-meta data may define various actions to be
taken based on the data node tag meta-data. These actions and their
definitions are outside the scope of this document. Users will need
to consider the security implications of any actions they choose to
define.
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9. Contributors
The authors would like to thank Ran Tao for his major contributions
to the initial modeling and use cases.
10. References
10.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[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>.
[RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for
Writing an IANA Considerations Section in RFCs", BCP 26,
RFC 8126, DOI 10.17487/RFC8126, June 2017,
<https://www.rfc-editor.org/info/rfc8126>.
[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>.
[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>.
[RFC8407] Bierman, A., "Guidelines for Authors and Reviewers of
Documents Containing YANG Data Models", BCP 216, RFC 8407,
DOI 10.17487/RFC8407, October 2018,
<https://www.rfc-editor.org/info/rfc8407>.
10.2. Informative References
[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>.
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[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>.
[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>.
Appendix A. Targeted data object subscription example
The following subsections provides targeted data object subscription
example.The subscription "id" values of 22 used below is just an
example. In production, the actual values of "id" might not be small
integers.
+-----------+ +-----------+
| Subscriber| | Publisher |
+------+----+ +-----+-----+
| |
| |
|Telemery data Tagging Advertisement
| (node-selector, opm-tag = metric)
|<---------------------------------|
| |
| establish-subscription |
| (datasore,node-selector) |
|--------------------------------->|
| |
| |
| |
| RPC Reply: OK, id = 22 |
|<---------------------------------|
| |
| |
| |
| Notification Message (for 22) |
| <--------------------------------|
| |
| |
| |
The publisher advertise telemetry data node capability to the
subscriber to instruct the receiver to subscribe targeted data object
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with specific characteristics (e.g., performance metric related data
object) and specific data path corresponding to the targeted data
object.
The following XML example [W3C.REC-xml-20081126] illustrates the
advertisment of the list of available target objects:
<?xml version="1.0" encoding="UTF-8"?>
<instance-data-set xmlns=\
"urn:ietf:params:xml:ns:yang:ietf-yang-instance-data">
<name>acme-router-notification-capabilities</name>
<content-schema>
<module>ietf-system-capabilities@2020-03-23</module>
<module>ietf-notification-capabilities@2020-03-23</module>
<module>ietf-data-export-capabilities@2020-03-23</module>
</content-schema>
<!-- revision date, contact, etc. -->
<description>Defines the notification capabilities of an acme-router.
The router only has running, and operational datastores.
Every change can be reported on-change from running, but
only config=true nodes and some config=false data from operational.
Statistics are not reported based on timer based trigger and counter
threshold based trigger.
</description>
<content-data>
<system-capabilities \
xmlns="urn:ietf:params:xml:ns:yang:ietf-system-capabilities" \
xmlns:inc=\
"urn:ietf:params:xml:ns:yang:ietf-notification-capabilities" \
xmlns:ds="urn:ietf:params:xml:ns:yang:ietf-datastores">
<datastore-capabilities>
<datastore>ds:operational</datastore>
<per-node-capabilities>
<node-selector>\
/if:interfaces/if:interface/if:statistics/if:in-errors\
</node-selector>
<sec:self-describing-capabilities>
<sec:self-tag-id>bandwith</sec:self-tag-id>
<sec:opm-tag>metric</sec:opm-tag>
</sec:self-describing-capabilities>
</per-node-capabilities>
</datastore-capabilities>
</system-capabilities>
</content-data>
</instance-data-set>
With telemetry data tagging information carried in the Telemetry data
Tagging Advertisement, the subscriber identifies targeted data object
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and associated data path to the datastore node and sends a establish-
subscription RPC to subscribe specific data objects that are
interests to the client application from the publisher.
<netconf: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">
<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">
/if:interfaces/if:interface/if:statistics/if:in-errors
</yp:datastore-xpath-filter>
<yp:periodic>
<yp:period>500</yp:period>
</yp:periodic>
</establish-subscription>
</netconf:rpc>
The publisher returns specific object type of operational state
related to the subscriber.
Authors' Addresses
Qin Wu
Huawei
101 Software Avenue, Yuhua District
Nanjing, Jiangsu 210012
China
Email: bill.wu@huawei.com
Benoit Claise
Cisco
De Kleetlaan 6a b1
Diegem 1831
Belgium
Email: bclaise@cisco.com
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Liang Geng
China Mobile
32 Xuanwumen West St, Xicheng District
Beijing 10053
Email: gengliang@chinamobile.com
Zongpeng Du
China Mobile
32 Xuanwumen West St, Xicheng District
Beijing 10053
Email: duzongpeng@chinamobile.com
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