rfc9196.original		rfc9196.txt
	NETCONF B. Lengyel		Internet Engineering Task Force (IETF) B. Lengyel
	Internet-Draft Ericsson		Request for Comments: 9196 Ericsson
	Intended status: Standards Track A. Clemm		Category: Standards Track A. Clemm
	Expires: 18 April 2022 Futurewei		ISSN: 2070-1721 Futurewei
	B. Claise		B. Claise
	Huawei		Huawei
	15 October 2021		February 2022
	YANG Modules describing Capabilities for Systems and Datastore Update		YANG Modules Describing Capabilities for Systems and Datastore Update
	Notifications		Notifications
	draft-ietf-netconf-notification-capabilities-21
	Abstract		Abstract
	This document defines two YANG modules,"ietf-system-capabilities" and		This document defines two YANG modules, "ietf-system-capabilities"
	"ietf-notification-capabilities".		and "ietf-notification-capabilities".
	The module "ietf-system-capabilities" provides a placeholder		The module "ietf-system-capabilities" provides a placeholder
	structure that can be used to discover YANG related system		structure that can be used to discover YANG-related system
	capabilities for servers. The module can be used to report		capabilities for servers. The module can be used to report
	capability information from the server at run time or at		capability information from the server at runtime or at
	implementation time, by making use of the YANG Instance Data File		implementation time by making use of the YANG instance data file
	Format.		format.
	The module "ietf-notification-capabilities" augments "ietf-system-		The module "ietf-notification-capabilities" augments "ietf-system-
	capabilities" to specify capabilities related to Subscription to YANG		capabilities" to specify capabilities related to "Subscription to
	Notifications for Datastore Updates.		YANG Notifications for Datastore Updates" (RFC 8641).
	Status of This Memo		Status of This Memo
	This Internet-Draft is submitted in full conformance with the		This is an Internet Standards Track document.
	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		This document is a product of the Internet Engineering Task Force
	and may be updated, replaced, or obsoleted by other documents at any		(IETF). It represents the consensus of the IETF community. It has
	time. It is inappropriate to use Internet-Drafts as reference		received public review and has been approved for publication by the
	material or to cite them other than as "work in progress."		Internet Engineering Steering Group (IESG). Further information on
			Internet Standards is available in Section 2 of RFC 7841.
	This Internet-Draft will expire on 18 April 2022.		Information about the current status of this document, any errata,
			and how to provide feedback on it may be obtained at
			https://www.rfc-editor.org/info/rfc9196.
	Copyright Notice		Copyright Notice
	Copyright (c) 2021 IETF Trust and the persons identified as the		Copyright (c) 2022 IETF Trust and the persons identified as the
	document authors. All rights reserved.		document authors. All rights reserved.
	This document is subject to BCP 78 and the IETF Trust's Legal		This document is subject to BCP 78 and the IETF Trust's Legal
	Provisions Relating to IETF Documents (https://trustee.ietf.org/		Provisions Relating to IETF Documents
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	and restrictions with respect to this document. Code Components		carefully, as they describe your rights and restrictions with respect
	extracted from this document must include Simplified BSD License text		to this document. Code Components extracted from this document must
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	provided without warranty as described in the Simplified BSD License.		Trust Legal Provisions and are provided without warranty as described
			in the Revised BSD License.
	Table of Contents		Table of Contents
	1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2		1. Introduction
	1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 4		1.1. Terminology
	2. Providing System Capability Information . . . . . . . . . . . 4		2. Providing System Capability Information
	3. Providing YANG-Push Notification Capabilities Information . . 5		3. Providing YANG-Push Notification Capabilities Information
	4. System Capabilities Model . . . . . . . . . . . . . . . . . . 6		4. System Capabilities Model
	4.1. Tree Diagram . . . . . . . . . . . . . . . . . . . . . . 7		4.1. Tree Diagram
	4.2. YANG Module . . . . . . . . . . . . . . . . . . . . . . . 7		4.2. YANG Module
	5. Notification Capabilities Model . . . . . . . . . . . . . . . 11		5. Notification Capabilities Model
	5.1. Tree Diagram . . . . . . . . . . . . . . . . . . . . . . 11		5.1. Tree Diagram
	5.2. YANG Module . . . . . . . . . . . . . . . . . . . . . . . 12		5.2. YANG Module
	6. Security Considerations . . . . . . . . . . . . . . . . . . . 18		6. Security Considerations
	7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 19		7. IANA Considerations
	7.1. The IETF XML Registry . . . . . . . . . . . . . . . . . . 19		7.1. The IETF XML Registry
	7.2. The YANG Module Names Registry . . . . . . . . . . . . . 19		7.2. The YANG Module Names Registry
	8. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 20		8. References
	9. References . . . . . . . . . . . . . . . . . . . . . . . . . 20		8.1. Normative References
	9.1. Normative References . . . . . . . . . . . . . . . . . . 20		8.2. Informative References
	9.2. Informative References . . . . . . . . . . . . . . . . . 21		Appendix A. Instance Data Example #1
	Appendix A. Instance data example #1 . . . . . . . . . . . . . . 22		Appendix B. Instance Data Example #2
	Appendix B. Instance data example #2 . . . . . . . . . . . . . . 24		Acknowledgments
	Appendix C. Changes between revisions . . . . . . . . . . . . . 25		Authors' Addresses
	Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 29
	1. Introduction		1. Introduction
	Servers and/or publishers often have capabilities, values describing		Servers and/or publishers often have capabilities, which can be
	operational behavior, that need to be conveyed to clients, which is		represented by values that designate operational behavior, that need
	enabled by the YANG modules described in this document.		to be conveyed to clients. The YANG modules that are defined in this
			document facilitate this.
	There is a need to publish this capability information as it is part		There is a need to publish this capability information as it is part
	of the API contract between the server and client. Examples include		of the API contract between the server and client. Examples include
	maximum size of data that can be stored or transferred, information		the maximum size of data that can be stored or transferred,
	about counters (whether a node supports "on-change" telemetry), etc.		information about counters (whether a node supports "on-change"
	Such capabilities are often dependent on a vendor's implementation or		telemetry), etc. Such capabilities are often dependent on a vendor's
	the available resources at deployment. Many such capabilities are		implementation or the available resources at deployment. Many such
	specific to the complete system, individual YANG datastores		capabilities are specific to the complete system, individual YANG
	[RFC8342], specific parts of the YANG schema, or even individual data		datastores [RFC8342], specific parts of the YANG schema, or even
	nodes. It is a goal of this document to provide a common way of		individual data nodes. It is a goal of this document to provide a
	representing such capabilities in a format that is:		common way to represent such capabilities in a format that is:
	* vendor independent		* vendor independent,
	* machine-readable		* machine readable, and
	* available in an identical format both at implementation time and		* available in an identical format both at implementation time and
	at run time.		at runtime.
	Implementation-time information is needed by Network Management		Implementation-time information is needed by Network Management
	System (NMS) implementers. An NMS implementation that supports		System (NMS) implementers. An NMS implementation that supports
	notifications needs the information about a system's capability so it		notifications needs information about a system's capability so it can
	can send "on-change" notifications. If the information is not		send "on-change" notifications. If the information is not documented
	documented in a way that is readily available to the NMS designer,		in a way that is readily available to the NMS designer, but only as
	but only as instance data from the network node once it is deployed,		instance data from the network node once it is deployed, the NMS
	the NMS implementation will be delayed, because it has to wait for		implementation will be delayed because it has to wait for the network
	the network node to be ready. In addition, the assumption that all		node to be ready. In addition, the assumption that all NMS
	NMS implementers will have a correctly configured network node		implementers will have a correctly configured network node available
	available to retrieve data from is an expensive proposition and may		from which to retrieve data is an expensive proposition and may not
	not always hold. (An NMS may need to be able to handle many dozens		always hold. (An NMS may need to be able to handle many dozens of
	of network node types.) Often a fully functional NMS is a		network node types.) Often, a fully functional NMS is a requirement
	requirement for introducing a new network node type into a network,		for introducing a new network node type into a network, so delaying
	so delaying NMS readiness effectively also delays the time at which a		NMS readiness effectively also delays the time at which a new network
	new network node type can be introduced into the network.		node type can be introduced into the network.
	Implementation-time information is needed by system integrators.		Implementation-time information is needed by system integrators.
	When introducing a network node type into their network, operators		When introducing a network node type into their network, operators
	often need to integrate the node type into their own management		often need to integrate the node type into their own management
	system. The NMS may have management functions that depend on "on-		system. The NMS may have management functions that depend on "on-
	change" notifications. The network operators need to plan their		change" notifications. The network operators need to plan their
	management practices and NMS implementation before they decide to buy		management practices and NMS implementation before they decide to buy
	the specific network node type. Moreover, the decision to buy the		the specific network node type. Moreover, the decision to buy the
	node type sometimes depends on these management possibilities.		node type sometimes depends on these management possibilities.
	Run-time capability information is needed:		Runtime capability information is needed:
	* for any "purely model driven" application, e.g., a NETCONF-		* for any "purely model-driven" application, e.g., a NETCONF
	browser. Such applications depend on reading models and		browser. Such applications depend on reading models and
	capabilities at run time to support all the publisher's available		capabilities at runtime to support all the publisher's available
	functionality.		functionality.
	* in case the capability might change during run time e.g., due to		* in case the capability might change during runtime, e.g., due to
	licensing, HW constraints etc.		licensing, hardware constraints, etc.
	* to check that capability information provided earlier, at		* to check that that capability information provided earlier, at
	implementation time, is what the publisher has implemented.		implementation time, is what the publisher has implemented.
	1.1. Terminology		1.1. Terminology
	The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",		The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
	"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and		"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
	"OPTIONAL" in this document are to be interpreted as described in BCP		"OPTIONAL" in this document are to be interpreted as described in
	14 [RFC2119] [RFC8174] when, and only when, they appear in all		BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
	capitals, as shown here.		capitals, as shown here.
	The terms "YANG-Push", "on-change subscription" and "periodic		The terms "YANG-Push", "on-change subscription", and "periodic
	subscription" are used as defined in [RFC8641].		subscription" are used as defined in [RFC8641].
	The terms "subscriber", "publisher" and "receiver" are used as		The terms "subscriber", "publisher", and "receiver" are used as
	defined in [RFC8639].		defined in [RFC8639].
	The term "server" is used as defined in [RFC8342].		The term "server" is used as defined in [RFC8342].
	The terms "YANG instance data file format", "instance data", and		The terms "YANG instance data file format", "instance data", and
	"instance data set" are used as defined in		"instance data set" are used as defined in [RFC9195].
	[I-D.ietf-netmod-yang-instance-file-format].
	In addition, this document defines the following terms:		In addition, this document defines the following terms:
	"Implementation-time information": Information about the server's		Implementation-time information: Information about the server's
	behavior that is made available during the implementation of the		behavior that is made available during the implementation of the
	server, available from a source other than a running server.		server, available from a source other than a running server.
	"Run-time information": Information about the server's behavior that		Runtime information: Information about the server's behavior that is
	is available from the running server via management protocols such as		available from the running server via management protocols such as
	NETCONF [RFC6241] or RESTCONF [RFC8040].		NETCONF [RFC6241] or RESTCONF [RFC8040].
	2. Providing System Capability Information		2. Providing System Capability Information
	Capability information is represented by instance-data based on one		Capability information is represented by instance data based on one
	or more "capability defining YANG modules". This allows a user to		or more "capability-defining YANG modules". This allows a user to
	discover capabilities both at implementation time and at run time.		discover capabilities both at implementation time and at runtime.
	* For the implementation-time use case: Capabilities SHOULD be		For the implementation-time use case: Capabilities SHOULD be
	provided by the implementer as YANG instance data files complying		provided by the implementer as YANG instance data files complying
	to [I-D.ietf-netmod-yang-instance-file-format]. When provided,		with [RFC9195]. When provided, the file MUST already be available
	the file MUST be available already at implementation time,		at implementation time and retrievable in a way that does not
	retrievable in a way that does not depend on a live network node.		depend on a live network node, e.g., downloading from a product
	E.g., download from product website.		website.
	* For the run-time use case: Capabilities SHOULD be available via		For the runtime use case: Capabilities SHOULD be available via
	NETCONF [RFC6241] or RESTCONF [RFC8040] from the live server		NETCONF [RFC6241] or RESTCONF [RFC8040] from the live server
	(implementing the publisher) during run time. Implementations		(implementing the publisher) during runtime. Implementations that
	that support changing these capabilities at run time SHOULD		support changing these capabilities at runtime SHOULD support "on-
	support "on-change" notifications about the system-capabilities		change" notifications about the system-capabilities container.
	container.
	The module "ietf-system-capabilities" provides a placeholder		The module "ietf-system-capabilities" provides a placeholder
	structure to be used to specify any YANG related system capability.		structure to be used to specify any YANG-related system capability.
	The module "ietf-notification-capabilities" is defined to allow a		The module "ietf-notification-capabilities" is defined to allow a
	publisher to specify capabilities related to "Subscription to YANG		publisher to specify capabilities related to "Subscription to YANG
	Notifications for Datastore Updates" [RFC8641], also known as YANG-		Notifications for Datastore Updates" [RFC8641], also known as YANG-
	Push, augmenting "ietf-system-capabilities".		Push, augmenting "ietf-system-capabilities".
	The YANG data models in this document conform to the Network		The YANG data models in this document conform to the Network
	Management Datastore Architecture (NMDA) defined in [RFC8342].		Management Datastore Architecture (NMDA) defined in [RFC8342].
	3. Providing YANG-Push Notification Capabilities Information		3. Providing YANG-Push Notification Capabilities Information
	A specific case is the need to specify capabilities in the YANG-Push		A specific case is the need to specify capabilities in the YANG-Push
	functionality. As defined in [RFC8641] a publisher may allow		functionality. As defined in [RFC8641], a publisher may allow
	subscribers to subscribe to updates from a datastore and will		subscribers to subscribe to updates from a datastore and will
	subsequently push such update notifications to the receiver.		subsequently push such update notifications to the receiver.
	Notifications may be sent periodically or "on-change" (more or less		Notifications may be sent periodically or "on change" (more or less
	immediately after each change).		immediately after each change).
	A publisher supporting YANG-Push has a number of capabilities defined		A publisher supporting YANG-Push has a number of capabilities defined
	in [RFC8641] that are often determined during the implementation of		in [RFC8641] that are often determined during the implementation of
	the publisher. These include:		the publisher. These include:
	* Supported (reporting) periods for "periodic" subscriptions		* supported (reporting) periods for "periodic" subscriptions.
	* Maximum number of objects that can be sent in an update		* the maximum number of objects that can be sent in an update.
	* The set of datastores or data nodes for which "periodic"		* the set of datastores or data nodes for which "periodic"
	notification is supported.		notification is supported.
	Additional capabilities if the optional "on-change" feature is		Additional capabilities if the optional "on-change" feature is
	supported include:		supported include:
	* Supported dampening periods for "on-change" subscriptions		* supported dampening periods for "on-change" subscriptions.
	* The set of datastores or data nodes for which "on-change"		* the set of datastores or data nodes for which "on-change"
	notification is supported		notification is supported.
	Publishers might have some capabilities (or limitations) to document.		Publishers might have some capabilities (or limitations) to document
	For example, how many update notifications and how many datastore		-- for example, how many update notifications and how many datastore
	node updates they can send out in a certain time-period. Other		node updates they can send out in a certain time period. Other
	publishers might not support "periodic" subscriptions to all		publishers might not support "periodic" subscriptions to all
	datastores. In some cases, a publisher supporting "on-change"		datastores. In some cases, a publisher supporting "on-change"
	notifications will not be able to push updates for some object types		notifications will not be able to push updates for some object types
	"on-change". Reasons for this might be that the value of the		"on change". Reasons for this might be that the value of the
	datastore node changes frequently (e.g., in-octets counter), that		datastore node changes frequently (e.g., in-octet counter), that
	small object changes are frequent and irrelevant to the receiver		small object changes are frequent and irrelevant to the receiver
	(e.g., a temperature gauge changing 0.1 degrees within a		(e.g., a temperature gauge changing 0.1 degrees within a
	predetermined and acceptable range), or that the implementation is		predetermined and acceptable range), or that the implementation is
	not capable of on-change notification for a particular object. In		not capable of on-change notification for a particular object. In
	all those cases, it will be important for subscriber applications to		all those cases, it will be important for subscriber applications to
	have a way to identify which objects "on-change" notifications are		have a way to identify the objects for which "on-change"
	supported and for which ones not.		notifications are supported and the objects for which they are not.
	Faced with the reality that support for "on-change" notification does		Support for "on-change" notifications does not mean that such
	not mean that such notifications will be sent for any specific data		notifications will be sent for any specific data node, as the ability
	node, subscriber/management applications can not rely on the "on-		to do so may not be supported for every data node. Therefore,
	change" functionality unless the subscriber has some means to		subscriber/management applications cannot rely on the "on-change"
	identify which objects "on-change" notifications are supported for.		functionality unless the subscriber has some means to identify the
	YANG models are meant to be used as an interface contract. Without		objects for which "on-change" notifications are in fact supported.
	identification of the data nodes actually supporting "on-change",		YANG data models are meant to be used as an interface contract.
	this contract would be incomplete.		Without identification of the data nodes actually supporting "on-
			change" notifications, this contract would be incomplete.
	Clients of a server (and subscribers to a publisher, as subscribers		Clients of a server (and subscribers to a publisher, as subscribers
	are also clients) need a method to gather capability information.		are also clients) need a method to gather capability information.
	4. System Capabilities Model		4. System Capabilities Model
	The module "ietf-system-capabilities" is defined to provide a		The module "ietf-system-capabilities" is defined to provide a
	structure that can be used to discover (as read-only operational		structure that can be used to discover (as a read-only operational
	state) any YANG related system capability.		state) any YANG-related system capability.
	This module itself does not contain any capabilities; it provides		This module itself does not contain any capabilities; it provides
	augmentation points for capabilities to be defined in subsequent YANG		augmentation points for capabilities to be defined in subsequent YANG
	modules. The ietf-system-capabilies is used by other modules to		modules. "ietf-system-capabilities" is used by other modules to
	augment in specific capability information. Every set of such		augment in specific capability information. Every set of such
	capabilities MUST be wrapped in a container under the augment		capabilities MUST be wrapped in a container under the augment
	statement to cleanly separate different groups of capabilities.		statement to cleanly separate different groups of capabilities.
	These "wrapper containers" SHALL be augmented in at /sysc:system-		These "wrapper containers" SHALL be augmented at /sysc:system-
	capabilities and /sysc:system-capabilities/sysc:datastore-		capabilities and /sysc:system-capabilities/sysc:datastore-
	capabilities/sysc:per-node-capabilities.		capabilities/sysc:per-node-capabilities.
	Capability values can be specified on system level, datastore level		Capability values can be specified at the system level, at the
	(by selecting all nodes in the datastore) or for specific data nodes		datastore level (by selecting all nodes in the datastore), or for
	of a specific datastore (and their contained sub-trees). Capability		specific data nodes of a specific datastore (and their contained
	values specified for a specific datastore or node-set override values		subtrees). Capability values specified for a specific datastore or
	specified on the system level.		node-set override values specified at the system level.
	Note: The solution is usable for both NMDA and non-NMDA systems. For		Note: The solution is usable for both NMDA and non-NMDA systems.
	non-NMDA servers "config false" data is considered as if it were part		For non-NMDA servers, "config false" data is considered as if it
	of the running datastore.		were part of the running datastore.
	4.1. Tree Diagram		4.1. Tree Diagram
	The following tree diagram [RFC8340] provides an overview of the data		The following tree diagram [RFC8340] provides an overview of the data
	model.		model.
	module: ietf-system-capabilities		module: ietf-system-capabilities
	+--ro system-capabilities		+--ro system-capabilities
	+--ro datastore-capabilities* [datastore]		+--ro datastore-capabilities* [datastore]
	+--ro datastore -> /yanglib:yang-library/datastore/name		+--ro datastore -> /yanglib:yang-library/datastore/name
	+--ro per-node-capabilities* []		+--ro per-node-capabilities* []
	+--ro (node-selection)?		+--ro (node-selection)?
	+--:(node-selector)		+--:(node-selector)
	+--ro node-selector? nacm:node-instance-identifier		+--ro node-selector? nacm:node-instance-identifier
	4.2. YANG Module		4.2. YANG Module
	This YANG module imports typedefs from [RFC8341] and a reference path		This YANG module imports typedefs from [RFC8341] and a reference path
	from [RFC8525].		from [RFC8525].
	<CODE BEGINS> file "ietf-system-capabilities@2021-10-12.yang"		<CODE BEGINS> file "ietf-system-capabilities@2022-01-21.yang"
	module ietf-system-capabilities {		module ietf-system-capabilities {
	yang-version 1.1;		yang-version 1.1;
	namespace "urn:ietf:params:xml:ns:yang:ietf-system-capabilities";		namespace "urn:ietf:params:xml:ns:yang:ietf-system-capabilities";
	prefix sysc;		prefix sysc;
	import ietf-netconf-acm {		import ietf-netconf-acm {
	prefix nacm;		prefix nacm;
	reference		reference
	"RFC 8341: Network Configuration Access Control Model";		"RFC 8341: Network Configuration Access Control Model";
	}		}
	skipping to change at page 8, line 4 ¶		skipping to change at line 325 ¶
	"RFC 8341: Network Configuration Access Control Model";		"RFC 8341: Network Configuration Access Control Model";
	}		}
	import ietf-yang-library {		import ietf-yang-library {
	prefix yanglib;		prefix yanglib;
	description		description
	"This module requires ietf-yang-library to be implemented.		"This module requires ietf-yang-library to be implemented.
	Revision 2019-01-04 or a revision derived from it		Revision 2019-01-04 or a revision derived from it
	is REQUIRED.";		is REQUIRED.";
	reference		reference
	"RFC8525: YANG Library";		"RFC8525: YANG Library";
	}		}
	organization		organization
	"IETF NETCONF (Network Configuration) Working Group";		"IETF NETCONF (Network Configuration) Working Group";
	contact		contact
	"WG Web: <https://datatracker.ietf.org/wg/netconf/>		"WG Web: <https://datatracker.ietf.org/wg/netconf/>
	WG List: <mailto:netconf@ietf.org>		WG List: <mailto:netconf@ietf.org>
	Editor: Balazs Lengyel		Editor: Balazs Lengyel
	<mailto:balazs.lengyel@ericsson.com>";		<mailto:balazs.lengyel@ericsson.com>";
	description		description
	"This module specifies a structure to specify system		"This module specifies a structure to specify system
	capabilities for a server or a publisher. System capabilities		capabilities for a server or a publisher. System capabilities
	may include capabilities of a NETCONF or RESTCONF server or a		may include capabilities of a NETCONF or RESTCONF server or a
	notification publisher.		notification publisher.
	This module does not contain any specific capabilities, it only		This module does not contain any specific capabilities; it only
	provides a structure where containers containing the actual		provides a structure where containers containing the actual
	capabilities are augmented in.		capabilities are augmented in.
	Capability values can be specified on system level,		Capability values can be specified at the system level, at the
	datastore level (by selecting all nodes in the datastore) or		datastore level (by selecting all nodes in the datastore), or
	for specific data nodes of a specific datastore (and their		for specific data nodes of a specific datastore (and their
	contained sub-trees).		contained subtrees).
	Capability values specified for a specific datastore or		Capability values specified for a specific datastore or
	node-set override values specified on the system/publisher level.		node-set override values specified on the system/publisher
			level.
	The same grouping MUST be used to define hierarchical capabilities		The same grouping MUST be used to define hierarchical
	supported both at the system level and datastore/data node level.		capabilities supported both at the system level and at the
			datastore/data-node level.
	To find a capability value for a specific data node in a		To find a capability value for a specific data node in a
	specific datastore the user SHALL:		specific datastore, the user SHALL:
	1) search for a datastore-capabilities list entry for		1) search for a datastore-capabilities list entry for
	the specific datastore. When stating a specific capability, the		the specific datastore. When stating a specific capability, the
	relative path for any specific capability must be the same		relative path for any specific capability must be the same
	under the system-capabilities container and under the		under the system-capabilities container and under the
	per-node-capabilities list.		per-node-capabilities list.
	2) If the datastore entry is found within that entry, process all		2) If the datastore entry is found within that entry, process
	per-node-capabilities entries in the order they appear in the list.		all per-node-capabilities entries in the order they appear in
	The first entry that specifies the specific capability and has a		the list. The first entry that specifies the specific
	node-selector selecting the specific data node defines the		capability and has a node-selector selecting the specific data
	capability value.		node defines the capability value.
	3) If the capability value is not found above and the specific		3) If the capability value is not found above and the specific
	capability is specified under the system-capabilities container		capability is specified under the system-capabilities container
	(outside the datastore-capabilities list), this value shall be		(outside the datastore-capabilities list), this value shall be
	used.		used.
	4) If no values are found in the previous steps, the		4) If no values are found in the previous steps, the
	system/publisher is not capable of providing a value. Possible		system/publisher is not capable of providing a value. Possible
	reasons are: it is unknown, the capability is changing for some		reasons are that it is unknown, the capability is changing for
	reason, there is no specified limit, etc. In this case the		some reason, there is no specified limit, etc. In this case,
	system's behavior is unspecified.		the system's behavior is unspecified.
	The key words 'MUST', 'MUST NOT', 'REQUIRED', 'SHALL',		The key words 'MUST', 'MUST NOT', 'REQUIRED', 'SHALL',
	'SHALL NOT', 'SHOULD', 'SHOULD NOT', 'RECOMMENDED',		'SHALL NOT', 'SHOULD', 'SHOULD NOT', 'RECOMMENDED',
	'NOT RECOMMENDED', 'MAY', and 'OPTIONAL' in this document		'NOT RECOMMENDED', 'MAY', and 'OPTIONAL' in this document
	are to be interpreted as described in BCP 14 (RFC 2119)		are to be interpreted as described in BCP 14 (RFC 2119)
	(RFC 8174) when, and only when, they appear in all		(RFC 8174) when, and only when, they appear in all
	capitals, as shown here.		capitals, as shown here.
	Copyright (c) 2021 IETF Trust and the persons identified as		Copyright (c) 2022 IETF Trust and the persons identified as
	authors of the code. All rights reserved.		authors of the code. All rights reserved.
	Redistribution and use in source and binary forms, with or		Redistribution and use in source and binary forms, with or
	without modification, is permitted pursuant to, and subject to		without modification, is permitted pursuant to, and subject to
	the license terms contained in, the Simplified BSD License set		the license terms contained in, the Revised BSD License set
	forth in Section 4.c of the IETF Trust's Legal Provisions		forth in Section 4.c of the IETF Trust's Legal Provisions
	Relating to IETF Documents		Relating to IETF Documents
	(https://trustee.ietf.org/license-info).		(https://trustee.ietf.org/license-info).
	This version of this YANG module is part of RFC XXXX		This version of this YANG module is part of RFC 9196
	(https://www.rfc-editor.org/info/rfcXXXX); see the RFC itself		(https://www.rfc-editor.org/info/rfc9196); see the RFC itself
	for full legal notices.";		for full legal notices.";
	// RFC Ed.: replace XXXX with actual RFC number and remove this		revision 2022-01-21 {
	// note.
	revision 2021-10-12 {
	description		description
	"Initial version		"Initial version";
	NOTE TO RFC EDITOR:
	(1)Please replace the above revision date to
	the date of RFC publication when published.
	(2) Please replace the date in the file name
	(ietf-system-capabilities@2021-10-12.yang)
	to the date of RFC publication.
	(3) Please replace the following reference
	with RFC number when published
	(i.e. RFC xxxx).";
	reference		reference
	"RFC XXXX: YANG Modules describing Capabilities for Systems		"RFC 9196: YANG Modules Describing Capabilities for Systems
	and Datastore Update Notifications";		and Datastore Update Notifications";
	}		}
	container system-capabilities {		container system-capabilities {
	config false;		config false;
	description		description
	"System capabilities.		"System capabilities.
	Capability values specified here at the system level		Capability values specified here at the system level
	are valid for all datastores and are used when the		are valid for all datastores and are used when the
	capability is not specified on the datastore level		capability is not specified at the datastore level
	or for specific data nodes.";		or for specific data nodes.";
	/*		/*
	* "Augmentation point for system level capabilities."		* "Augmentation point for system-level capabilities."
	*/		*/
	list datastore-capabilities {		list datastore-capabilities {
	key "datastore";		key "datastore";
	description		description
	"Capabilities values per datastore.		"Capabilities values per datastore.
	For non-NMDA servers/publishers 'config false' data is		For non-NMDA servers/publishers, 'config false' data is
	considered as if it was part of the running datastore.";		considered as if it were part of the running datastore.";
	leaf datastore {		leaf datastore {
	type leafref {		type leafref {
	path		path
	"/yanglib:yang-library/yanglib:datastore/yanglib:name";		"/yanglib:yang-library/yanglib:datastore/yanglib:name";
	}		}
	description		description
	"The datastore for which capabilities are defined.		"The datastore for which capabilities are defined.
	Only one specific datastore can be specified		Only one specific datastore can be specified,
	e.g., ds:conventional, which represents a set of		e.g., ds:conventional must not be used, as it
	configuration datastores, must not be used.";		represents a set of configuration datastores.";
	}		}
	list per-node-capabilities {		list per-node-capabilities {
	description		description
	"Each list entry specifies capabilities for the selected		"Each list entry specifies capabilities for the selected
	data nodes. The same capabilities apply for the data nodes		data nodes. The same capabilities apply to the data nodes
	in the subtree below the selected nodes.		in the subtree below the selected nodes.
	The system SHALL order the entries according to their		The system SHALL order the entries according to their
	precedence. The order of the entries MUST NOT change unless		precedence. The order of the entries MUST NOT change
	the underlying capabilities also change.		unless the underlying capabilities also change.
	Note that the longest patch matching can be achieved		Note that the longest patch matching can be achieved
	by ordering more specific matches before less		by ordering more specific matches before less
	specific ones.";		specific ones.";
	choice node-selection {		choice node-selection {
	description		description
	"A method to select some or all nodes within a datastore.";		"A method to select some or all nodes within a
			datastore.";
	leaf node-selector {		leaf node-selector {
	type nacm:node-instance-identifier;		type nacm:node-instance-identifier;
	description		description
	"Selects the data nodes for which capabilities are		"Selects the data nodes for which capabilities are
	specified. The special value '/' denotes all data nodes		specified. The special value '/' denotes all data
	in the datastore, consistent with the path leaf node on		nodes in the datastore, consistent with the path
	page 41 [RFC8341].";		leaf node on page 41 of [RFC8341].";
	reference		reference
	"RFC 8341: Network Configuration Access Control Model";		"RFC 8341: Network Configuration Access Control Model";
	}		}
	}		}
	/*		/*
	* "Augmentation point for datastore or data node level		* "Augmentation point for datastore- or data-node-level
	* capabilities."		* capabilities."
	*/		*/
	}		}
	}		}
	}		}
	}		}
	<CODE ENDS>		<CODE ENDS>
	<CODE ENDS>
	5. Notification Capabilities Model		5. Notification Capabilities Model
	The YANG module "ietf-notification-capabilities" provides YANG-Push		The YANG module "ietf-notification-capabilities" provides information
	related capability information.		related to the YANG-Push capability.
	5.1. Tree Diagram		5.1. Tree Diagram
	The following tree diagram [RFC8340] provides an overview of the data		The following tree diagram [RFC8340] provides an overview of the data
	model.		model.
	module: ietf-notification-capabilities		module: ietf-notification-capabilities
	augment /sysc:system-capabilities:		augment /sysc:system-capabilities:
	+--ro subscription-capabilities		+--ro subscription-capabilities
	+--ro max-nodes-per-update? uint32		+--ro max-nodes-per-update? uint32
	skipping to change at page 12, line 44 ¶		skipping to change at line 528 ¶
	| {yp:on-change}?		| {yp:on-change}?
	+--ro supported-excluded-change-type* union		+--ro supported-excluded-change-type* union
	{yp:on-change}?		{yp:on-change}?
	5.2. YANG Module		5.2. YANG Module
	This YANG module imports a feature and typedefs from [RFC8641] and		This YANG module imports a feature and typedefs from [RFC8641] and
	also imports the "ietf-system-capabilities" specified in this		also imports the "ietf-system-capabilities" specified in this
	document.		document.
	<CODE BEGINS> file "ietf-notification-capabilities@2021-10-12.yang"		<CODE BEGINS> file "ietf-notification-capabilities@2022-01-21.yang"
	module ietf-notification-capabilities {		module ietf-notification-capabilities {
	yang-version 1.1;		yang-version 1.1;
	namespace		namespace
	"urn:ietf:params:xml:ns:yang:ietf-notification-capabilities";		"urn:ietf:params:xml:ns:yang:ietf-notification-capabilities";
	prefix notc;		prefix notc;
	import ietf-yang-push {		import ietf-yang-push {
	prefix yp;		prefix yp;
	description		description
	"This module requires ietf-yang-push to be implemented.";		"This module requires ietf-yang-push to be implemented.";
	reference		reference
	"RFC 8641: Subscription to YANG Notifications for Datastore		"RFC 8641: Subscription to YANG Notifications for
	Updates";		Datastore Updates";
	}		}
	import ietf-system-capabilities {		import ietf-system-capabilities {
	prefix sysc;		prefix sysc;
	description		description
	"This module requires ietf-system-capabilities to be		"This module requires ietf-system-capabilities to be
	implemented.";		implemented.";
	reference		reference
	"RFC XXXX: YANG Modules describing Capabilities for Systems		"RFC 9196: YANG Modules Describing Capabilities for Systems
	and Datastore Update Notifications";		and Datastore Update Notifications";
	}		}
	// RFC Ed.: replace the above XXXX with actual RFC number
	// and remove this note.
	organization		organization
	"IETF NETCONF (Network Configuration) Working Group";		"IETF NETCONF (Network Configuration) Working Group";
	contact		contact
	"WG Web: <https://datatracker.ietf.org/wg/netconf/>		"WG Web: <https://datatracker.ietf.org/wg/netconf/>
	WG List: <mailto:netconf@ietf.org>		WG List: <mailto:netconf@ietf.org>
	Editor: Balazs Lengyel		Editor: Balazs Lengyel
	<mailto:balazs.lengyel@ericsson.com>";		<mailto:balazs.lengyel@ericsson.com>";
	description		description
	"This module specifies YANG-Push [RFC 8641] related publisher		"This module specifies publisher capabilities related to
	capabilities.		YANG-Push (RFC 8641).
	The module contains:		The module contains:
	- specification of which data nodes support 'on-change' or		- a specification of the data nodes that support 'on-change' or
	'periodic' notifications.		'periodic' notifications.
	- capabilities related to the throughput of notification data		- capabilities related to the throughput of notification data
	that the publisher can support. (Note that for a specific		that the publisher can support. (Note that for a specific
	subscription, the publisher MAY allow only longer periods		subscription, the publisher MAY allow only longer periods
	or smaller updates depending on, e.g., actual load conditions.)		or smaller updates depending on, e.g., actual load conditions.)
	Capability values can be specified on system/publisher level,		Capability values can be specified at the system/publisher
	datastore level or for specific data nodes of a specific		level, at the datastore level, or for specific data nodes of
	datastore (and their contained sub-trees), as defined in the		a specific datastore (and their contained subtrees), as defined
	ietf-system-capabilities module.		in the ietf-system-capabilities module.
	If different data nodes covered by a single subscription		If different data nodes covered by a single subscription
	have different values for a specific capability, then using		have different values for a specific capability, then using
	values that are only acceptable for some of these data nodes,		values that are only acceptable for some of these data nodes,
	but not for others, may result in the rejection of the		but not for others, may result in the rejection of the
	subscription.		subscription.
	The key words 'MUST', 'MUST NOT', 'REQUIRED', 'SHALL',		The key words 'MUST', 'MUST NOT', 'REQUIRED', 'SHALL',
	'SHALL NOT', 'SHOULD', 'SHOULD NOT', 'RECOMMENDED',		'SHALL NOT', 'SHOULD', 'SHOULD NOT', 'RECOMMENDED',
	'NOT RECOMMENDED', 'MAY', and 'OPTIONAL' in this document		'NOT RECOMMENDED', 'MAY', and 'OPTIONAL' in this document
	are to be interpreted as described in BCP 14 (RFC 2119)		are to be interpreted as described in BCP 14 (RFC 2119)
	(RFC 8174) when, and only when, they appear in all		(RFC 8174) when, and only when, they appear in all
	capitals, as shown here.		capitals, as shown here.
	Copyright (c) 2021 IETF Trust and the persons identified as		Copyright (c) 2022 IETF Trust and the persons identified as
	authors of the code. All rights reserved.		authors of the code. All rights reserved.
	Redistribution and use in source and binary forms, with or		Redistribution and use in source and binary forms, with or
	without modification, is permitted pursuant to, and subject to		without modification, is permitted pursuant to, and subject to
	the license terms contained in, the Simplified BSD License set		the license terms contained in, the Revised BSD License set
	forth in Section 4.c of the IETF Trust's Legal Provisions		forth in Section 4.c of the IETF Trust's Legal Provisions
	Relating to IETF Documents		Relating to IETF Documents
	(https://trustee.ietf.org/license-info).		(https://trustee.ietf.org/license-info).
	This version of this YANG module is part of RFC XXXX		This version of this YANG module is part of RFC 9196
	(https://www.rfc-editor.org/info/rfcXXXX); see the RFC itself		(https://www.rfc-editor.org/info/rfc9196); see the RFC itself
	for full legal notices.";		for full legal notices.";
	// RFC Ed.: replace XXXX with actual RFC number and remove this		revision 2022-01-21 {
	// note.
	revision 2021-10-12 {
	description		description
	"Initial version";		"Initial version";
	reference		reference
	"RFC XXXX: YANG Modules describing Capabilities for Systems		"RFC 9196: YANG Modules Describing Capabilities for Systems
	and Datastore Update Notifications";		and Datastore Update Notifications";
	}		}
	// RFC Ed.: replace XXXX with actual RFC number and remove this
	// note.
	grouping subscription-capabilities {		grouping subscription-capabilities {
	description		description
	"Capabilities related to YANG-Push subscriptions		"Capabilities related to YANG-Push subscriptions
	and notifications";		and notifications";
	container subscription-capabilities {		container subscription-capabilities {
	description		description
	"Capabilities related to YANG-Push subscriptions		"Capabilities related to YANG-Push subscriptions
	and notifications";		and notifications";
	typedef notification-support {		typedef notification-support {
	type bits {		type bits {
	bit config-changes {		bit config-changes {
	description		description
	"The publisher is capable of sending		"The publisher is capable of sending
	notifications for 'config true' nodes for the		notifications for 'config true' nodes for the
	relevant scope and subscription type.";		relevant scope and subscription type.";
	}		}
	bit state-changes {		bit state-changes {
	description		description
	"The publisher is capable of sending		"The publisher is capable of sending
	notifications for 'config false' nodes for the relevant		notifications for 'config false' nodes for the
	scope and subscription type.";		relevant scope and subscription type.";
	}		}
	}		}
	description		description
	"Type for defining whether 'on-change' or		"Type for defining whether 'on-change' or
	'periodic' notifications are supported for all data nodes,		'periodic' notifications are supported for all data nodes,
	'config false' data nodes, 'config true' data nodes, or		'config false' data nodes, 'config true' data nodes, or
	no data nodes.		no data nodes.
	If the bit config-changes or state-changes is set		The bits config-changes or state-changes have no effect
	for a datastore, or a set of nodes that does not contain		when they are set for a datastore or for a set of nodes
	nodes with the indicated config value, this has no		that does not contain nodes with the indicated config
	effect, as if no support was declared. E.g. indicating		value. In those cases, the effect is the same as if no
	support for state-changes for a candidate datastore has		support was declared. One example of this is indicating
	no effect.";		support for state-changes for a candidate datastore that
			has no effect.";
	}		}
	leaf max-nodes-per-update {		leaf max-nodes-per-update {
	type uint32 {		type uint32 {
	range "1..max";		range "1..max";
	}		}
	description		description
	"Maximum number of data nodes that can be sent		"Maximum number of data nodes that can be sent
	in an update. The publisher MAY support more data nodes,		in an update. The publisher MAY support more data nodes
	but SHOULD support at least this number.		but SHOULD support at least this number.
	May be used to avoid the 'update-too-big' error		May be used to avoid the 'update-too-big' error
	during subscription.";		during subscription.";
	reference		reference
	"RFC 8641: Subscription to YANG Notifications for Datastore		"RFC 8641: Subscription to YANG Notifications for
	Updates, the 'update-too-big' error/identity";		Datastore Updates, the 'update-too-big' error/identity";
	}		}
	leaf periodic-notifications-supported {		leaf periodic-notifications-supported {
	type notification-support;		type notification-support;
	description		description
	"Specifies whether the publisher is capable of		"Specifies whether the publisher is capable of
	sending 'periodic' notifications for the selected		sending 'periodic' notifications for the selected
	data nodes including any subtrees that may exist		data nodes, including any subtrees that may exist
	below them.";		below them.";
	reference		reference
	"RFC 8641: Subscription to YANG Notifications for Datastore		"RFC 8641: Subscription to YANG Notifications for
	Updates, 'periodic' subscription concept";		Datastore Updates, 'periodic' subscription concept";
	}		}
	choice update-period {		choice update-period {
	description		description
	"Supported update period value or values for		"Supported update period value or values for
	'periodic' subscriptions.";		'periodic' subscriptions.";
	leaf minimum-update-period {		leaf minimum-update-period {
	type uint32;		type uint32;
	units "centiseconds";		units "centiseconds";
	description		description
	"Indicates the minimal update period that is		"Indicates the minimal update period that is
	supported for a 'periodic' subscription.		supported for a 'periodic' subscription.
	A subscription request to the selected data nodes with		A subscription request to the selected data nodes with
	a smaller period than what this leaf specifies is		a smaller period than what this leaf specifies is
	likely to result in a 'period-unsupported' error.";		likely to result in a 'period-unsupported' error.";
	reference		reference
	"RFC 8641: Subscription to YANG Notifications for Datastore		"RFC 8641: Subscription to YANG Notifications for
	Updates, the period leaf in the ietf-yang-push YANG		Datastore Updates, the period leaf in the ietf-yang-push
	module";		YANG module";
	}		}
	leaf-list supported-update-period {		leaf-list supported-update-period {
	type uint32;		type uint32;
	units "centiseconds";		units "centiseconds";
	description		description
	"Supported update period values for a 'periodic'		"Supported update period values for a 'periodic'
	subscription.		subscription.
	A subscription request to the selected data nodes with a		A subscription request to the selected data nodes with a
	period not included in the leaf-list will result in a		period not included in the leaf-list will result in a
	'period-unsupported' error.";		'period-unsupported' error.";
	reference		reference
	"RFC 8641: Subscription to YANG Notifications for Datastore		"RFC 8641: Subscription to YANG Notifications for
	Updates, the period leaf in the ietf-yang-push YANG		Datastore Updates, the period leaf in the ietf-yang-push
	module";		YANG module";
	}		}
	}		}
	leaf on-change-supported {		leaf on-change-supported {
	if-feature "yp:on-change";		if-feature "yp:on-change";
	type notification-support;		type notification-support;
	description		description
	"Specifies whether the publisher is capable of		"Specifies whether the publisher is capable of
	sending 'on-change' notifications for the selected		sending 'on-change' notifications for the selected
	data nodes and the subtree below them.";		data nodes and the subtree below them.";
	reference		reference
	"RFC 8641: Subscription to YANG Notifications for Datastore		"RFC 8641: Subscription to YANG Notifications for Datastore
	Updates, on-change concept";		Updates, on-change concept";
	}		}
	leaf minimum-dampening-period {		leaf minimum-dampening-period {
	if-feature "yp:on-change";		if-feature "yp:on-change";
	type uint32;		type uint32;
	units "centiseconds";		units "centiseconds";
	description		description
	"The minimum dampening-period supported for 'on-change'		"The minimum dampening period supported for 'on-change'
	subscriptions for the selected data nodes.		subscriptions for the selected data nodes.
	If this value is present and greater than zero,		If this value is present and greater than zero,
	that implies dampening is mandatory.";		that implies dampening is mandatory.";
	reference		reference
	"RFC 8641: Subscription to YANG Notifications for		"RFC 8641: Subscription to YANG Notifications for
	Datastore Updates, the dampening-period leaf in the		Datastore Updates, the dampening-period leaf in the
	ietf-yang-push YANG module";		ietf-yang-push YANG module";
	}		}
	leaf-list supported-excluded-change-type {		leaf-list supported-excluded-change-type {
	skipping to change at page 18, line 17 ¶		skipping to change at line 782 ¶
	refine		refine
	"subscription-capabilities/supported-excluded-change-type" {		"subscription-capabilities/supported-excluded-change-type" {
	default "none";		default "none";
	}		}
	}		}
	}		}
	augment "/sysc:system-capabilities/sysc:datastore-capabilities"		augment "/sysc:system-capabilities/sysc:datastore-capabilities"
	+ "/sysc:per-node-capabilities" {		+ "/sysc:per-node-capabilities" {
	description		description
	"Add datastore and node level capabilities";		"Add datastore and node-level capabilities";
	uses subscription-capabilities {		uses subscription-capabilities {
	refine		refine
	"subscription-capabilities/supported-excluded-change-type" {		"subscription-capabilities/supported-excluded-change-type" {
	default "none";		default "none";
	}		}
	}		}
	}		}
	}		}
	<CODE ENDS>		<CODE ENDS>
	skipping to change at page 19, line 4 ¶		skipping to change at line 817 ¶
	RESTCONF users to a preconfigured subset of all available NETCONF or		RESTCONF users to a preconfigured subset of all available NETCONF or
	RESTCONF protocol operations and content.		RESTCONF protocol operations and content.
	This document outlines a framework for conveying system capability		This document outlines a framework for conveying system capability
	information that is inherently flexible and extensible. While the		information that is inherently flexible and extensible. While the
	full set of use cases is not known now, they may range as wide as		full set of use cases is not known now, they may range as wide as
	conveying the minimum update period for periodic subscription updates		conveying the minimum update period for periodic subscription updates
	and what protocols might be used for such notifications. Knowledge		and what protocols might be used for such notifications. Knowledge
	of this type of value might, for example, allow an attacker to gain		of this type of value might, for example, allow an attacker to gain
	insight into how long unauthorized configuration changes might be		insight into how long unauthorized configuration changes might be
	active prior to detection, and what communications channels might be		active prior to detection and what communications channels might be
	disrupted to extend the period of non-detection. Documents adding		disrupted to extend the period of non-detection. Documents adding
	additional capabilities via augmenting this module are encouraged to		additional capabilities via augmenting this module are encouraged to
	document the security considerations of the new YANG nodes, according		document the security considerations of the new YANG nodes, according
	to the guidance in BCP 216.		to the guidance in BCP 216 [RFC8407].
	All protocol-accessible data nodes in augmented modules are read-only		All protocol-accessible data nodes in augmented modules are read-only
	and cannot be modified. The data in these modules is not security		and cannot be modified. Access control may be configured to avoid
	sensitive. Access control may be configured, to avoid exposing the		exposing any read-only data that is defined by the augmenting module
	read-only data.		documentation as being security sensitive.
	When that data is in file format, data should be protected against		When that data is in file format, the data should be protected
	modification or unauthorized access using normal file handling		against modification or unauthorized access using normal file-
	mechanisms. The data in file format also inherits all the security		handling mechanisms. The data in file format also inherits all the
	considerations of [I-D.ietf-netmod-yang-instance-file-format] which		security considerations of [RFC9195], which includes additional
	has additional considerations about read protections; and		considerations about read protections and distinguishes between data
	distinguishes between data at rest and in motion.		at rest and in motion.
	7. IANA Considerations		7. IANA Considerations
	7.1. The IETF XML Registry		7.1. The IETF XML Registry
	This document registers two URIs in the IETF XML registry [RFC3688].		This document registers the following URIs in the "IETF XML Registry"
	Following the format in [RFC3688], the following registrations are		[RFC3688]:
	requested:
	URI: urn:ietf:params:xml:ns:yang:ietf-system-capabilities		URI: urn:ietf:params:xml:ns:yang:ietf-system-capabilities
	Registrant Contact: The NETCONF WG of the IETF.		Registrant Contact: The IESG.
	XML: N/A, the requested URI is an XML namespace.		XML: N/A, the requested URI is an XML namespace.
	URI: urn:ietf:params:xml:ns:yang:ietf-notification-capabilities		URI: urn:ietf:params:xml:ns:yang:ietf-notification-capabilities
	Registrant Contact: The NETCONF WG of the IETF.		Registrant Contact: The IESG.
	XML: N/A, the requested URI is an XML namespace.		XML: N/A, the requested URI is an XML namespace.
	7.2. The YANG Module Names Registry		7.2. The YANG Module Names Registry
	This document registers two YANG modules in the YANG Module Names		This document registers the following YANG modules in the "YANG
	registry [RFC6020]. Following the format in [RFC6020], the following		Module Names" registry [RFC6020]:
	registrations are requested:
	name: ietf-system-capabilities
	namespace: urn:ietf:params:xml:ns:yang:ietf-system-capabilities
	prefix: sysc
	reference: RFC XXXX
	name: ietf-notification-capabilities
	namespace:
	urn:ietf:params:xml:ns:yang:ietf-notification-capabilities
	prefix: notc
	reference: RFC XXXX
	8. Acknowledgments
	For their valuable comments, discussions, and feedback, we wish to		name: ietf-system-capabilities
	acknowledge Andy Bierman, Juergen Schoenwaelder, Rob Wilton, Kent		namespace: urn:ietf:params:xml:ns:yang:ietf-system-capabilities
	Watsen, Eric Voit, Joe Clarke, Martin Bjorklund, Ladislav Lhotka, Qin		prefix: sysc
	Wu, Mahesh Jethanandani, Ran Tao, Reshad Rahman and other members of		reference: RFC 9196
	the Netmod WG.
	9. References		name: ietf-notification-capabilities
			namespace: urn:ietf:params:xml:ns:yang:ietf-notification-
			capabilities
			prefix: notc
			reference: RFC 9196
	9.1. Normative References		8. References
	[I-D.ietf-netmod-yang-instance-file-format]		8.1. Normative References
	Lengyel, B. and B. Claise, "YANG Instance Data File
	Format", Work in Progress, Internet-Draft, draft-ietf-
	netmod-yang-instance-file-format-19, 16 September 2021,
	<https://www.ietf.org/archive/id/draft-ietf-netmod-yang-
	instance-file-format-19.txt>.
	[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate		[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
	Requirement Levels", BCP 14, RFC 2119,		Requirement Levels", BCP 14, RFC 2119,
	DOI 10.17487/RFC2119, March 1997,		DOI 10.17487/RFC2119, March 1997,
	<https://www.rfc-editor.org/info/rfc2119>.		<https://www.rfc-editor.org/info/rfc2119>.
	[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,		[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
	DOI 10.17487/RFC3688, January 2004,		DOI 10.17487/RFC3688, January 2004,
	<https://www.rfc-editor.org/info/rfc3688>.		<https://www.rfc-editor.org/info/rfc3688>.
	[RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for		[RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for
	the Network Configuration Protocol (NETCONF)", RFC 6020,		the Network Configuration Protocol (NETCONF)", RFC 6020,
	DOI 10.17487/RFC6020, October 2010,		DOI 10.17487/RFC6020, October 2010,
	<https://www.rfc-editor.org/info/rfc6020>.		<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>.
			[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		[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
	2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,		2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
	May 2017, <https://www.rfc-editor.org/info/rfc8174>.		May 2017, <https://www.rfc-editor.org/info/rfc8174>.
	[RFC8341] Bierman, A. and M. Bjorklund, "Network Configuration		[RFC8341] Bierman, A. and M. Bjorklund, "Network Configuration
	Access Control Model", STD 91, RFC 8341,		Access Control Model", STD 91, RFC 8341,
	DOI 10.17487/RFC8341, March 2018,		DOI 10.17487/RFC8341, March 2018,
	<https://www.rfc-editor.org/info/rfc8341>.		<https://www.rfc-editor.org/info/rfc8341>.
	[RFC8342] Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K.,		[RFC8342] Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K.,
	and R. Wilton, "Network Management Datastore Architecture		and R. Wilton, "Network Management Datastore Architecture
	(NMDA)", RFC 8342, DOI 10.17487/RFC8342, March 2018,		(NMDA)", RFC 8342, DOI 10.17487/RFC8342, March 2018,
	<https://www.rfc-editor.org/info/rfc8342>.		<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.,		[RFC8525] Bierman, A., Bjorklund, M., Schoenwaelder, J., Watsen, K.,
	and R. Wilton, "YANG Library", RFC 8525,		and R. Wilton, "YANG Library", RFC 8525,
	DOI 10.17487/RFC8525, March 2019,		DOI 10.17487/RFC8525, March 2019,
	<https://www.rfc-editor.org/info/rfc8525>.		<https://www.rfc-editor.org/info/rfc8525>.
	[RFC8639] Voit, E., Clemm, A., Gonzalez Prieto, A., Nilsen-Nygaard,		[RFC8639] Voit, E., Clemm, A., Gonzalez Prieto, A., Nilsen-Nygaard,
	E., and A. Tripathy, "Subscription to YANG Notifications",		E., and A. Tripathy, "Subscription to YANG Notifications",
	RFC 8639, DOI 10.17487/RFC8639, September 2019,		RFC 8639, DOI 10.17487/RFC8639, September 2019,
	<https://www.rfc-editor.org/info/rfc8639>.		<https://www.rfc-editor.org/info/rfc8639>.
	[RFC8641] Clemm, A. and E. Voit, "Subscription to YANG Notifications		[RFC8641] Clemm, A. and E. Voit, "Subscription to YANG Notifications
	for Datastore Updates", RFC 8641, DOI 10.17487/RFC8641,		for Datastore Updates", RFC 8641, DOI 10.17487/RFC8641,
	September 2019, <https://www.rfc-editor.org/info/rfc8641>.		September 2019, <https://www.rfc-editor.org/info/rfc8641>.
	9.2. Informative References		[RFC9195] Lengyel, B. and B. Claise, "A File Format for YANG
			Instance Data", RFC 9195, DOI 10.17487/RFC9195, February
	[RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,		2022, <https://www.rfc-editor.org/info/rfc9195>.
	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>.
	[RFC8040] Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF		8.2. Informative References
	Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017,
	<https://www.rfc-editor.org/info/rfc8040>.
	[RFC8340] Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams",		[RFC8340] Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams",
	BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018,		BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018,
	<https://www.rfc-editor.org/info/rfc8340>.		<https://www.rfc-editor.org/info/rfc8340>.
	[RFC8446] Rescorla, E., "The Transport Layer Security (TLS) Protocol		[RFC8407] Bierman, A., "Guidelines for Authors and Reviewers of
	Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018,		Documents Containing YANG Data Models", BCP 216, RFC 8407,
	<https://www.rfc-editor.org/info/rfc8446>.		DOI 10.17487/RFC8407, October 2018,
			<https://www.rfc-editor.org/info/rfc8407>.
	[RFC8792] Watsen, K., Auerswald, E., Farrel, A., and Q. Wu,		[RFC8792] Watsen, K., Auerswald, E., Farrel, A., and Q. Wu,
	"Handling Long Lines in Content of Internet-Drafts and		"Handling Long Lines in Content of Internet-Drafts and
	RFCs", RFC 8792, DOI 10.17487/RFC8792, June 2020,		RFCs", RFC 8792, DOI 10.17487/RFC8792, June 2020,
	<https://www.rfc-editor.org/info/rfc8792>.		<https://www.rfc-editor.org/info/rfc8792>.
	Appendix A. Instance data example #1		Appendix A. Instance Data Example #1
	The following examples use artwork folding [RFC8792] for better		The following examples use artwork folding [RFC8792] for better
	formatting.		formatting.
	The following instance data example describes the notification		The following instance data example describes the notification
	capabilities of a hypothetical "acme-router". The router implements		capabilities of a hypothetical "acme-router". The router implements
	the running and operational datastores. Every change can be reported		the running and operational datastores. Every change can be reported
	"on-change" from the running datastore, but only "config false" nodes		"on-change" from the running datastore, but only "config false" nodes
	and some "config false" data from the operational datastore.		and some "config false" data can be reported on-change from the
	Interface statistics are not reported "on-change", only two important		operational datastore. Interface statistics are not reported "on-
	counters. Datastore subscription capabilities are not reported "on-		change"; only two important counters are. Datastore subscription
	change", as they never change on the acme-router during run time.		capabilities are not reported "on-change", as they never change on
			the acme-router during runtime.
	========== NOTE: '\' line wrapping per RFC 8792) ===========
	<?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@2021-10-12</module>
	<module>ietf-notification-capabilities@2021-10-12</module>
	</content-schema>
	<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 the running
	datastore, but only "config false" nodes and some "config
	false" data from the operational datastore. Statistics are
	not reported on-change except for two important counters,
	where a small dampening period is mandated.
	</description>
	<content-data>
	<system-capabilities \
	xmlns="urn:ietf:params:xml:ns:yang:ietf-system-capabilities" \
	xmlns:notc=\
	"urn:ietf:params:xml:ns:yang:ietf-notification-capabilities" \
	xmlns:ds="urn:ietf:params:xml:ns:yang:ietf-datastores">
	<notc:subscription-capabilities>
	<notc:minimum-update-period>500</notc:minimum-update-period>
	<notc:max-nodes-per-update>2000</notc:max-nodes-per-update>
	<notc:minimum-dampening-period>100</notc:minimum-dampening-period>
	<notc:periodic-notifications-supported>\
	config-changes state-changes\
	</notc:periodic-notifications-supported>
	<notc:on-change-supported>\
	config-changes state-changes\
	</notc:on-change-supported>		========== NOTE: '\' line wrapping per RFC 8792) ===========
	<notc:supported-excluded-change-type>\
	all\
	</notc:supported-excluded-change-type>
	</notc:subscription-capabilities>
	<datastore-capabilities>
	<datastore>ds:operational</datastore>
	<per-node-capabilities>
	<node-selector>\
	/if:interfaces/if:interface[if:name='lo']\
	</node-selector>
	<notc:subscription-capabilities>
	<notc:on-change-supported/>
	<notc:periodic-notifications-supported/>
	</notc:subscription-capabilities>
	</per-node-capabilities>
	<per-node-capabilities>
	<node-selector>\
	/if:interfaces/if:interface/if:statistics/if:in-octets\
	</node-selector>
	<notc:subscription-capabilities>
	<notc:minimum-dampening-period>10
	</notc:minimum-dampening-period>
	<notc:on-change-supported>\
	state-changes\
	</notc:on-change-supported>
	</notc:subscription-capabilities>
	</per-node-capabilities>
	<per-node-capabilities>
	<node-selector>\
	/if:interfaces/if:interface/if:statistics/if:out-octets\
	</node-selector>
	<notc:subscription-capabilities>
	<notc:minimum-dampening-period>10
	</notc:minimum-dampening-period>
	<notc:on-change-supported>\
	state-changes\
	</notc:on-change-supported>
	</notc:subscription-capabilities>
	</per-node-capabilities>
	<per-node-capabilities>
	<node-selector>\
	/if:interfaces/if:interface/if:statistics\
	</node-selector>
	<notc:subscription-capabilities>
	<notc:on-change-supported/>
	</notc:subscription-capabilities>
	</per-node-capabilities>
	</datastore-capabilities>		<?xml version="1.0" encoding="UTF-8"?>
	</system-capabilities>		<instance-data-set xmlns=\
	</content-data>		"urn:ietf:params:xml:ns:yang:ietf-yang-instance-data">
	</instance-data-set>		<name>acme-router-notification-capabilities</name>
			<content-schema>
			<module>ietf-system-capabilities@2022-01-21</module>
			<module>ietf-notification-capabilities@2022-01-21</module>
			</content-schema>
			<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 the
			running datastore, but only "config false" nodes and some
			"config false" data can be reported on-change from the
			operational datastore. Statistics
			are not reported on-change except for two important counters,
			where a small dampening period is mandated.
			</description>
			<content-data>
			<system-capabilities \
			xmlns="urn:ietf:params:xml:ns:yang:ietf-system-capabilities" \
			xmlns:notc=\
			"urn:ietf:params:xml:ns:yang:ietf-notification-capabilities" \
			xmlns:ds="urn:ietf:params:xml:ns:yang:ietf-datastores">
			<notc:subscription-capabilities>
			<notc:minimum-update-period>500</notc:minimum-update-period>
			<notc:max-nodes-per-update>2000</notc:max-nodes-per-update>
			<notc:minimum-dampening-period>\
			100\
			</notc:minimum-dampening-period>
			<notc:periodic-notifications-supported>\
			config-changes state-changes\
			</notc:periodic-notifications-supported>
			<notc:on-change-supported>\
			config-changes state-changes\
			</notc:on-change-supported>
			<notc:supported-excluded-change-type>\
			all\
			</notc:supported-excluded-change-type>
			</notc:subscription-capabilities>
			<datastore-capabilities>
			<datastore>ds:operational</datastore>
			<per-node-capabilities>
			<node-selector>\
			/if:interfaces/if:interface[if:name='lo']\
			</node-selector>
			<notc:subscription-capabilities>
			<notc:on-change-supported/>
			<notc:periodic-notifications-supported/>
			</notc:subscription-capabilities>
			</per-node-capabilities>
			<per-node-capabilities>
			<node-selector>\
			/if:interfaces/if:interface/if:statistics/if:in-octets\
			</node-selector>
			<notc:subscription-capabilities>
			<notc:minimum-dampening-period>10
			</notc:minimum-dampening-period>
			<notc:on-change-supported>\
			state-changes\
			</notc:on-change-supported>
			</notc:subscription-capabilities>
			</per-node-capabilities>
			<per-node-capabilities>
			<node-selector>\
			/if:interfaces/if:interface/if:statistics/if:out-octets\
			</node-selector>
			<notc:subscription-capabilities>
			<notc:minimum-dampening-period>10
			</notc:minimum-dampening-period>
			<notc:on-change-supported>\
			state-changes\
			</notc:on-change-supported>
			</notc:subscription-capabilities>
			</per-node-capabilities>
			<per-node-capabilities>
			<node-selector>\
			/if:interfaces/if:interface/if:statistics\
			</node-selector>
			<notc:subscription-capabilities>
			<notc:on-change-supported/>
			</notc:subscription-capabilities>
			</per-node-capabilities>
			</datastore-capabilities>
			</system-capabilities>
			</content-data>
			</instance-data-set>
	Figure 1: Notification Capabilities with data node specific settings		Figure 1: Notification Capabilities with Settings Specific to the
			Data Node
	Appendix B. Instance data example #2		Appendix B. Instance Data Example #2
	The following examples use artwork folding [RFC8792] for better		The following examples use artwork folding [RFC8792] for better
	formatting.		formatting.
	The following instance data example describes the notification		The following instance data example describes the notification
	capabilities of a hypothetical "acme-switch". The switch implements		capabilities of a hypothetical "acme-switch". The switch implements
	the running, candidate and operational datastores. Every change can		the running, candidate, and operational datastores. Every change can
	be reported "on-change" from the running datastore, nothing from the		be reported "on-change" from the running datastore, nothing can be
	candidate datastore and all "config false" data from the operational		reported on-change from the candidate datastore, and all "config
	datastore. "periodic" subscriptions are supported for running and		false" data can be reported on-change from the operational datastore.
	operational, but not for candidate datastores.		"Periodic" subscriptions are supported for running and operational
			but not for candidate datastores.
	========== NOTE: '\' line wrapping per RFC 8792) ===========
	<?xml version="1.0" encoding="UTF-8"?>
	<instance-data-set xmlns=\
	"urn:ietf:params:xml:ns:yang:ietf-yang-instance-data">
	<name>acme-switch-notification-capabilities</name>
	<content-schema>
	<module>ietf-system-capabilities@2021-10-12</module>
	<module>ietf-notification-capabilities@2021-10-12</module>
	</content-schema>
	<description>Notification capabilities of acme-switch.
	Acme-switch implements the running, candidate and operational
	datastores. Every change can be reported on-change from the
	running datastore, nothing from the candidate datastore and
	all "config false" data from the operational datastore. Periodic
	subscriptions are supported for running and operational, but not
	for candidate datastore.
	</description>
	<content-data>
	<system-capabilities \
	xmlns="urn:ietf:params:xml:ns:yang:ietf-system-capabilities" \
	xmlns:notc=\
	"urn:ietf:params:xml:ns:yang:ietf-notification-capabilities" \
	xmlns:ds="urn:ietf:params:xml:ns:yang:ietf-datastores">
	<notc:subscription-capabilities>
	<notc:minimum-update-period>500</notc:minimum-update-period>
	<notc:max-nodes-per-update>2000</notc:max-nodes-per-update>
	<notc:minimum-dampening-period>100</notc:minimum-dampening-period>
	<notc:periodic-notifications-supported>\
	config-changes state-changes\
	</notc:periodic-notifications-supported>
	</notc:subscription-capabilities>
	<datastore-capabilities>
	<datastore>ds:operational</datastore>
	<per-node-capabilities>
	<node-selector>/</node-selector>
	<notc:subscription-capabilities>
	<notc:on-change-supported>\
	state-changes\
	</notc:on-change-supported>
	</notc:subscription-capabilities>
	</per-node-capabilities>
	</datastore-capabilities>
	<datastore-capabilities>
	<datastore>ds:candidate</datastore>
	<per-node-capabilities>
	<node-selector>/</node-selector>
	<notc:subscription-capabilities>
	<notc:on-change-supported/>
	<notc:periodic-notifications-supported/>
	</notc:subscription-capabilities>
	</per-node-capabilities>
	</datastore-capabilities>
	<datastore-capabilities>
	<datastore>ds:running</datastore>
	<per-node-capabilities>
	<node-selector>/</node-selector>
	<notc:subscription-capabilities>
	<notc:on-change-supported>\
	config-changes\
	</notc:on-change-supported>
	</notc:subscription-capabilities>
	</per-node-capabilities>
	</datastore-capabilities>
	</system-capabilities>
	</content-data>
	</instance-data-set>
	Figure 2: Notification Capabilities with datastore level settings
	Appendix C. Changes between revisions
	Note to RFC Editor (To be removed by RFC Editor)
	v20 - v21
	* IESG review
	v19 - v20
	* IESG review
	v18 - v19
	* IESG review
	v17 - v18
	* IESG review
	v16 - v17
	* AD review comments addressed
	v15 - v16
	* Two editorial comments from document shepherd
	v14 - v15
	* Address the last comments from document shepherd
	v13 - v14
	* Updated according to sheperds review
	* Added to import, which imported modules need to be implemented.
	* Added notes to the RFC editor
	* Re-arrange the sections, for a better reading flow
	* Many editorial changes
	* Replace YANG module prefix
	v12 - v13
	* Rearranged order of notification capability leafs into 3 groups:
	generic, specific to periodic subscriptions, specific to on-
	change.
	* Introduced artwork folding in the examples
	* Updated to follow draft-ietf-netmod-yang-instance-file-format-10
	* Various editing changes
	v11 - v12
	* Updated max-nodes-per-update description
	* Reformatted YANG models with pyang -f yang --keep-comments --yang-
	line-length 69
	v10 - v11
	* Updated examples
	* Updated typedef notification-support
	v09 - v10
	* Removed description text from imports about the need for
	implementing the imported module.
	* Changed notification-support to bits with shorter names
	* Assigned enum values to supported-excluded-change-type
	* Made node-selector a choice to allow for future alternative
	selection methods.
	* Changed precedence of per-node-capabilities entries. Precedence
	is now according to the position of entries in the list.
	v08 - v09
	* Split the YANG module into two: ietf-system-capabilities and ietf-
	notification-capabilities. Restructured/updated the draft
	accordingly.
	v07 - v08
	* Prepared the YANG model to include other non-YANG-Push related
	capabilities.
	* Renamed the top level container to system-capabilities
	* Added a container subscription-capabilities to the grouping
	subscription-capabilities to contain all subscription related
	capabilities
	* Updated examples according to draft-ietf-netmod-yang-instance-
	file-format-06.
	v06 - v07
	* Updated examples according to draft-ietf-netmod-yang-instance-
	file-format-05.
	v05 - v06
	* Providing the capability data is only a "SHOULD" recommendation.
	Some reviewers wanted MUST some wanted much less.
	* The YANG module import statements now indicate the imported
	modules that must be implemented not just available as import as
	requested by the YangDoctors review.
	v04 - v05
	* Added new capabilities periodic-notifications-supported and
	supported-excluded-change-type.
	* Restructured YANG module to make the node-selector's usage similar
	to how NACM uses it: "/" means the whole datastore.
	* Small corrections, spelling, rewording
	* Replaced the term server with the term publisher except in cases
	where we speak about datastores and functionality based on get,
	getconfig operations. In this latter case it is really the server
	functionality that is discussed.
	v03 - v04
	* Clarified recommended support for on-change notifications about
	the datastore-subscription-capabilities.
	v02 - v03
	* Allow throughput related capabilities to be defined on top,
	datastore or data node level. Described that specific capability
	values always override generic ones.
	* Indicate that non-NMDA servers can also use this model.
	* Updated according to draft-ietf-netmod-yang-instance-file-
	format-04
	v01 - v02
	* Added instance data examples
	* On-change capability can be defined per datastore		========== NOTE: '\' line wrapping per RFC 8792) ===========
	* Added "if-feature yp:on-change" where relevant		<?xml version="1.0" encoding="UTF-8"?>
			<instance-data-set xmlns=\
			"urn:ietf:params:xml:ns:yang:ietf-yang-instance-data">
			<name>acme-switch-notification-capabilities</name>
			<content-schema>
			<module>ietf-system-capabilities@2022-01-21</module>
			<module>ietf-notification-capabilities@2022-01-21</module>
			</content-schema>
			<description>Notification capabilities of acme-switch.
			Acme-switch implements the running, candidate, and operational
			datastores. Every change can be reported on-change from the
			running datastore, nothing from the candidate datastore and
			all "config false" data from the operational datastore. Periodic
			subscriptions are supported for running and operational, but not
			for candidate datastore.
			</description>
			<content-data>
			<system-capabilities \
			xmlns="urn:ietf:params:xml:ns:yang:ietf-system-capabilities" \
			xmlns:notc=\
			"urn:ietf:params:xml:ns:yang:ietf-notification-capabilities" \
			xmlns:ds="urn:ietf:params:xml:ns:yang:ietf-datastores">
			<notc:subscription-capabilities>
			<notc:minimum-update-period>500</notc:minimum-update-period>
			<notc:max-nodes-per-update>2000</notc:max-nodes-per-update>
			<notc:minimum-dampening-period>\
			100\
			</notc:minimum-dampening-period>
			<notc:periodic-notifications-supported>\
			config-changes state-changes\
			</notc:periodic-notifications-supported>
			</notc:subscription-capabilities>
			<datastore-capabilities>
			<datastore>ds:operational</datastore>
			<per-node-capabilities>
			<node-selector>/</node-selector>
			<notc:subscription-capabilities>
			<notc:on-change-supported>\
			state-changes\
			</notc:on-change-supported>
			</notc:subscription-capabilities>
			</per-node-capabilities>
			</datastore-capabilities>
			<datastore-capabilities>
			<datastore>ds:candidate</datastore>
			<per-node-capabilities>
			<node-selector>/</node-selector>
			<notc:subscription-capabilities>
			<notc:on-change-supported/>
			<notc:periodic-notifications-supported/>
			</notc:subscription-capabilities>
			</per-node-capabilities>
			</datastore-capabilities>
			<datastore-capabilities>
			<datastore>ds:running</datastore>
			<per-node-capabilities>
			<node-selector>/</node-selector>
			<notc:subscription-capabilities>
			<notc:on-change-supported>\
			config-changes\
			</notc:on-change-supported>
			</notc:subscription-capabilities>
			</per-node-capabilities>
			</datastore-capabilities>
			</system-capabilities>
			</content-data>
			</instance-data-set>
	* Unified units used		Figure 2: Notification Capabilities with Datastore-Level Settings
	v00 - v01		Acknowledgments
	* Add more capabilities: minimum period, supported period max-number		For their valuable comments, discussions, and feedback, we wish to
	of objects, min dampening period, dampening supported		acknowledge Andy Bierman, Juergen Schoenwaelder, Rob Wilton, Kent
			Watsen, Eric Voit, Joe Clarke, Martin Bjorklund, Ladislav Lhotka, Qin
			Wu, Mahesh Jethanandani, Ran Tao, Reshad Rahman, and other members of
			the Netmod Working Group.
	Authors' Addresses		Authors' Addresses
	Balazs Lengyel		Balazs Lengyel
	Ericsson		Ericsson
	1117 Budapest		Budapest
	Magyar Tudosok korutja 11		Magyar Tudosok korutja 11
			1117
	Hungary		Hungary
	Email: balazs.lengyel@ericsson.com		Email: balazs.lengyel@ericsson.com
	Alexander Clemm		Alexander Clemm
	Futurewei		Futurewei
	2330 Central Expressway		2330 Central Expressway
	Santa Clara, CA 95050,		Santa Clara, CA 95050
	United States of America		United States of America
	Email: ludwig@clemm.org		Email: ludwig@clemm.org
	Benoit Claise		Benoit Claise
	Huawei		Huawei
			George's Court Townsend Street
			Dublin 2
			Ireland
	Email: benoit.claise@huawei.com		Email: benoit.claise@huawei.com
End of changes. 144 change blocks.
	663 lines changed or deleted		484 lines changed or added
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