draft-ietf-netmod-yang-model-classification-01.txt   draft-ietf-netmod-yang-model-classification-02.txt 
NETMOD D. Bogdanovic NETMOD D. Bogdanovic
Internet-Draft Internet-Draft Volta Networks, Inc.
Intended status: Informational B. Claise Intended status: Informational B. Claise
Expires: October 6, 2016 C. Moberg Expires: December 24, 2016 C. Moberg
Cisco Systems, Inc. Cisco Systems, Inc.
April 4, 2016 June 22, 2016
YANG Model Classification YANG Module Classification
draft-ietf-netmod-yang-model-classification-01 draft-ietf-netmod-yang-model-classification-02
Abstract Abstract
The YANG [RFC6020] data modeling language is currently being The YANG [RFC6020] data modeling language is currently being
considered for a wide variety of applications throughout the considered for a wide variety of applications throughout the
networking industry at large. Many standards-defining organizations networking industry at large. Many standards-defining organizations
(SDOs), open source software projects, vendors and users are using (SDOs), open source software projects, vendors and users are using
YANG to develop and publish models of configuration, state data and YANG to develop and publish YANG modules of configuration, state data
operations for a wide variety of applications. At the same time, and operations for a wide variety of applications. At the same time,
there is currently no well-known terminology to categorize various there is currently no well-known terminology to categorize various
types of YANG models. types of YANG modules.
A consistent terminology would help with the categorization of A consistent terminology would help with the categorization of YANG
models, assist in the analysis the YANG data modeling efforts in the modules, assist in the analysis the YANG data modeling efforts in the
IETF and other organizations, and bring clarity to the YANG-related IETF and other organizations, and bring clarity to the YANG-related
discussions between the different groups. discussions between the different groups.
This document describes a set of concepts and associated terms to This document describes a set of concepts and associated terms to
support consistent classification of YANG models. support consistent classification of YANG modules.
Status of This Memo Status of This Memo
This Internet-Draft is submitted in full conformance with the This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79. provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/. Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on October 6, 2016. This Internet-Draft will expire on December 24, 2016.
Copyright Notice Copyright Notice
Copyright (c) 2016 IETF Trust and the persons identified as the Copyright (c) 2016 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 Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of (http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. First Dimension: YANG Model Abstraction Layers . . . . . . . 3 1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 4
2.1. Network Service YANG Data Models . . . . . . . . . . . . 4 2. First Dimension: YANG Data Model Abstraction Layers . . . . . 4
2.2. Network Element YANG Data models . . . . . . . . . . . . 5 2.1. Network Service YANG Modules . . . . . . . . . . . . . . 6
3. Second Dimension: Model Types . . . . . . . . . . . . . . . . 6 2.2. Network Element YANG Modules . . . . . . . . . . . . . . 7
3.1. Standard YANG Models . . . . . . . . . . . . . . . . . . 6 3. Second Dimension: Module Types . . . . . . . . . . . . . . . 7
3.2. Vendor-specific YANG Models and Extensions . . . . . . . 6 3.1. Standard YANG Modules . . . . . . . . . . . . . . . . . . 8
3.3. User-specific YANG Models and Extensions . . . . . . . . 7 3.2. Vendor-specific YANG Modules and Extensions . . . . . . . 8
3.4. Adding Models to Catalogs . . . . . . . . . . . . . . . . 7 3.3. User-specific YANG Modules and Extensions . . . . . . . . 9
3.5. Security Considerations . . . . . . . . . . . . . . . . . 8 4. Adding The Classification Type to YANG Module Catalogs . . . 9
3.6. IANA Considerations . . . . . . . . . . . . . . . . . . . 8 5. Security Considerations . . . . . . . . . . . . . . . . . . . 10
3.7. Acknowledgements . . . . . . . . . . . . . . . . . . . . 8 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10
3.8. Change log [RFC Editor: Please remove] . . . . . . . . . 8 7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 10
4. References . . . . . . . . . . . . . . . . . . . . . . . . . 8 8. Change log [RFC Editor: Please remove] . . . . . . . . . . . 10
4.1. Normative References . . . . . . . . . . . . . . . . . . 8 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 11
4.2. Informative References . . . . . . . . . . . . . . . . . 8 9.1. Normative References . . . . . . . . . . . . . . . . . . 11
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 9 9.2. Informative References . . . . . . . . . . . . . . . . . 11
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 12
1. Introduction 1. Introduction
The Internet Engineering Steering Group (IESG) has been actively The Internet Engineering Steering Group (IESG) has been actively
encouraging IETF working groups to use the NETCONF [RFC6241] and YANG encouraging IETF working groups to use the YANG [RFC6020]
standards for configuration management purposes, especially in new [I-D.ietf-netmod-rfc6020bis] and NETCONF [RFC6241] and YANG standards
working group charters [Writable-MIB-Module-IESG-Statement]. for configuration management purposes, especially in new working
group charters [Writable-MIB-Module-IESG-Statement].
YANG is also gaining wide acceptance as the de-facto standard YANG is also gaining wide acceptance as the de-facto standard
modeling language in the broader industry. This extends beyond the modeling language in the broader industry. This extends beyond the
IETF, including many standards development organizations, industry IETF, including many standards development organizations, industry
consortia, ad hoc groups, open source projects, vendors, and end- consortia, ad hoc groups, open source projects, vendors, and end-
users. users.
There are currently no clear guidelines on how to classify the There are currently no clear guidelines on how to classify the
layering of YANG models according to abstraction, or how to classify layering of YANG modules according to abstraction, or how to classify
models along the continuum spanning formal standards publications, modules along the continuum spanning formal standards publications,
vendor-specific models and models provided by end-users. vendor-specific modules and modules provided by end-users.
This document presents a set of concepts and terms to form a useful This document presents a set of concepts and terms to form a useful
taxonomy for consistent classification of YANG models in two taxonomy for consistent classification of YANG modules in two
dimensions: dimensions:
o The layering of models based on their abstraction levels o The layering of modules based on their abstraction levels
o The type of model based on the nature and intent of the content o The type of module based on the nature and intent of the content
The two categories are covered in the next two sections. The intent of this document is to provide a taxonomy to simplify
human communication around YANG modules. The authors acknowledge
that the classification boundaries are at times blurry, but believe
that this document should provide a robust starting point as the YANG
community gain further experience with designing and deploying
modules. To be more explicit, the authors believe that the
classification criteria will change over time.
2. First Dimension: YANG Model Abstraction Layers An example of a type of module that have created substantial
discussion during the development of this document is topologies.
Topology models are useful both on the Network Element level (e.g.
link-state database content) as well as in the Network Service level
(e.g. network-wide, configured topologies). In the end, it is the
module developer that classifies the module according to the initial
intent of the module content.
Model developers have taken two approaches to developing YANG models: This document should provide benefits to multiple audiences:
top-down and bottom-up. The top-down approach starts with high level
abstractions modeling business or customer requirements and maps them o First, a common taxonomy helps with the different standards
to specific networking technologies. The bottom-up approach starts development organizations and industry consortia discussions,
with fundamental networking technologies and maps them into more whose goals are determined in their respective areas of work.
abstract constructs.
o Second, operators might look at the YANG module classification
type to understand which Network Service YANG modules and Network
Element YANG modules are available for their service composition.
It is difficult to determine the module type without inspecting
the YANG module itself. The YANG module name might provide some
useful information but is not a definite answer. For example, an
L2VPN YANG module might be a Network Service YANG module, ready to
be used by the operators. Alternatively, it might be a Network
Element YANG module that contains the L2VPN data definitions
required to be configured on a single device.
o And thirdly, this taxonomy would help equipment vendors (whether
physical or virtual), controller vendors, orchestrator vendors to
explain to their customers the relationship between the different
YANG modules they propose in their products. See Figure 1.
1.1. Terminology
RFC6020bis [I-D.ietf-netmod-rfc6020bis] specifies:
o data model: A data model describes how data is represented and
accessed.
o module: A YANG module defines a hierarchy of nodes that can be
used for NETCONF-based operations. With its definitions and the
definitions it imports or includes from elsewhere, a module is
self-contained and "compilable".
2. First Dimension: YANG Data Model Abstraction Layers
Model developers have taken two approaches to developing YANG
modules: top-down and bottom-up. The top-down approach starts with
high level abstractions modeling business or customer requirements
and maps them to specific networking technologies. The bottom-up
approach starts with fundamental networking technologies and maps
them into more abstract constructs.
There are currently no specific requirements on, or well-defined best There are currently no specific requirements on, or well-defined best
practices around the development of models. For the purpose of this practices around the development of YANG modules For the purpose of
document we assume that both approaches (bottom-up and top-down) will this document we assume that both approaches (bottom-up and top-down)
be used as they both provide benefits that appeal to different will be used as they both provide benefits that appeal to different
groups. groups.
For layering purposes, this document suggests the classification of For layering purposes, this document suggests the classification of
data models into two distinct abstraction layers: YANG modules into two distinct abstraction layers:
o Network Element YANG Models describe the configuration, state data o Network Element YANG Modules describe the configuration, state
and operations of specific device-centric technologies or features data and operations of specific device-centric technologies or
features
o Network Service YANG Models describe the configuration, state data o Network Service YANG Modules describe the configuration, state
and operations of an abstract representation of a service data and operations of an abstract representation of a service
implemented on one or multiple network elements implemented on one or multiple network elements
Figure 1 illustrates the application of YANG models at different Figure 1 illustrates the application of YANG modules at different
layers of abstraction. Layering of models allows for reusability of layers of abstraction. Layering of modules allows for reusability of
existing lower layer models by higher level models while limiting existing lower layer modules by higher level modules while limiting
duplication of features across layers. duplication of features across layers.
For model developers, per-layer modeling allows for separation of For module developers, per-layer modeling allows for separation of
concern across editing teams focusing on specific areas. concern across editing teams focusing on specific areas.
As an example, experience from the IETF shows that creating useful As an example, experience from the IETF shows that creating useful
network element YANG models for e.g. routing or switching protocols network element YANG modules for e.g. routing or switching protocols
requires teams that include developers with experience of requires teams that include developers with experience of
implementing those protocols. implementing those protocols.
On the other hand, network service models are best developed by On the other hand, network service YANG modules are best developed by
people experienced in defining network services for consumption by network operators experienced in defining network services for
programmers developing e.g. flow-through provisioning systems or consumption by programmers developing e.g. flow-through provisioning
self-service portals. systems or self-service portals.
+--------------------------+ +--------------------------+
| Operations and Business | | Operations and Business |
| Support Systems | | Support Systems |
| (OSS/BSS) | | (OSS/BSS) |
+--------------------------+ +--------------------------+
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Network Service YANG data models Network Service YANG Modules
+------------+ +-------------+ +-------------+ +------------+ +-------------+ +-------------+
| | | | | | | | | | | |
| - VPWS | | - VPLS | | L3VPN | | - L2VPN | | - L2VPN | | L3VPN |
| - L2VPN | | - L2VPN | | | | - VPWS | | - VPLS | | |
| | | | | | | | | | | |
+------------+ +-------------+ +-------------+ +------------+ +-------------+ +-------------+
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Network Element YANG data models Network Element YANG Modules
+------------+ +------------+ +-------------+ +------------+ +------------+ +------------+ +-------------+ +------------+
| | | | | | | | | | | | | | | |
| MPLS | | BGP | | IPv4 & IPv6 | | Ethernet | | MPLS | | BGP | | IPv4 / IPv6 | | Ethernet |
| | | | | | | | | | | | | | | |
+------------+ +------------+ +-------------+ +------------+ +------------+ +------------+ +-------------+ +------------+
Fig. 1 YANG Model Layers L2VPN: Layer 2 Virtual Private Network
L3VPN: Layer 3 Virtual Private Network
VPWS: Virtual Private Wire Service
VPLS: Virtual Private LAN Service
2.1. Network Service YANG Data Models Figure 1: YANG Module Layers
Network Service YANG Data Models describe the characteristics of a 2.1. Network Service YANG Modules
Network Service YANG Modules describe the characteristics of a
service, as agreed upon with consumers of that service. That is, a service, as agreed upon with consumers of that service. That is, a
service model does not expose the detailed configuration parameters service model does not expose the detailed configuration parameters
of all participating network elements and features, but describes an of all participating network elements and features, but describes an
abstract model that allows instances of the service to be decomposed abstract model that allows instances of the service to be decomposed
into instance data according to the Network Element data models of into instance data according to the Network Element Modules of the
the participating network elements. The service-to-element participating network elements. The service-to-element decomposition
decomposition is a separate process with details depending on how the is a separate process with details depending on how the network
network operator chooses to realize the service. For the purpose of operator chooses to realize the service. For the purpose of this
this document we will use the term "orchestrator" to describe a document we will use the term "orchestrator" to describe a system
system implementing such a process. implementing such a process.
As an example, the Network Service model included in As an example, the Network Service YANG Module included in
[YANG-Data-Model-for-L3VPN-service-delivery] provides an abstracted [YANG-Data-Model-for-L3VPN-service-delivery] provides an abstract
model for Layer 3 IP VPN service configuration. An orchestrator model for Layer 3 IP VPN service configuration. This model includes
receives operations on service instances according to the service e.g. the concept of a 'site-network-access' to represent bearer and
model and decomposes the data into specific Network Element models to connection parameters. An orchestrator receives operations on
configure the participating network elements to perform the intent of service instances according to the service model and decomposes the
the service. data into specific Network Element Modules to configure the
participating network elements to perform the intent of the service.
In the case of the L3VPN module, this would include translating the
'site-network-access' parameters to the appropriate parameters in the
Network Element YANG Module implemented on the constituent elements.
Network Service YANG models define services models to be consumed by Network Service YANG Modules define services models to be consumed by
external systems. These models are commonly designed, developed and external systems. These modules are commonly designed, developed and
deployed by network infrastructure teams. deployed by network infrastructure teams.
YANG allows for different design patterns to describe network YANG allows for different design patterns to describe network
services, ranging from monolithic to component-based approaches. services, ranging from monolithic to component-based approaches.
The monolithic approach captures the entire service in a single model The monolithic approach captures the entire service in a single
and does not put focus on reusability of internal data definitions module and does not put focus on reusability of internal data
and groupings. The monolithic approach has the advantages of single- definitions and groupings. The monolithic approach has the
purpose development including speed at the expense of reusability. advantages of single-purpose development including speed at the
expense of reusability.
The component-based approach captures device-centric features (e.g. The component-based approach captures device-centric features (e.g.
the definition of a VRF, routing protocols, or packet filtering) in a the definition of a VRF, routing protocols, or packet filtering) in a
vendor-independent manner. The components are designed for reuse vendor-independent manner. The components are designed for reuse
across many services. The set of components required for a specific across many service modules. The set of components required for a
service is then composed into the higher-level service. The specific service is then composed into the higher-level service. The
component-based approach has the advantages of modular development component-based approach has the advantages of modular development
including a higher degree of reusability at the expense of initial including a higher degree of reusability at the expense of initial
speed. speed.
As an example, an L2VPN service can be built on many different types As an example, an L2VPN service can be built on many different types
of transport network technologies, including e.g. MPLS or carrier of transport network technologies, including e.g. MPLS or carrier
ethernet. A component-based approach would allow for reuse of e.g. ethernet. A component-based approach would allow for reuse of e.g.
UNI-interface definitions independent of the underlying transport UNI-interface definitions independent of the underlying transport
network (e.g. MEF UNI interface or MPLS interface). The monolithic network (e.g. MEF UNI interface or MPLS interface). The monolithic
approach would assume a specific set of transport technologies and approach would assume a specific set of transport technologies and
interface definitions. interface definitions.
2.2. Network Element YANG Data models 2.2. Network Element YANG Modules
Network Element YANG Data Models describe the configuration, state Network Element YANG Modules describe the configuration, state data
data and operations of a network device as defined by the vendor of and operations of a network device as defined by the vendor of that
that device. The models are commonly structured around features of device. The modules are commonly structured around features of the
the device, e.g. interface configuration [RFC7223], OSPF device, e.g. interface configuration [RFC7223], OSPF configuration
configuration [I-D.ietf-ospf-yang], and firewall rules definitions [I-D.ietf-ospf-yang], and firewall rules definitions
[I-D.ietf-netmod-acl-model]. The model provides a coherent data [I-D.ietf-netmod-acl-model].
model representation of what is commonly a very mixed software
environment consisting of the operating system and applications
running on the device.
The decomposition, ordering, and execution of changes to the The module provides a coherent data model representation of what is
operating system and application configuration is the task of the commonly a very mixed software environment consisting of the
management framework that implements the YANG model. operating system and applications running on the device. The
decomposition, ordering, and execution of changes to the operating
system and application configuration is the task of the management
framework that implements the YANG module.
3. Second Dimension: Model Types 3. Second Dimension: Module Types
This document suggests classifying YANG model types as either This document suggests classifying YANG module types as either
standard YANG models, vendor-specific YANG models and extensions, and standard YANG modules, vendor-specific YANG modules and extensions,
user-specific YANG models and extensions and user-specific YANG modules and extensions
The suggested classification applies to both Network Element YANG The suggested classification applies to both Network Element YANG
Data Models and Network Service YANG Data Models. Modules and Network Service YANG Modules.
It is to be expected that real-world implementations of both Network It is to be expected that real-world implementations of both Network
Service and Network Element models will include a mix of all three Service and Network Element YANG Modules will include a mix of all
types of models. three types of modules.
3.1. Standard YANG Models Figure 2 illustrates the relationship between the three types of
modules.
Standard YANG models are published by standards-defining +--------------+
| User |
| Extensions |
+------+-------+
Augments
+------+-------+ +--------------+ +--------------+
| Vendor | | User | | User |
| Extensions | | Extensions | | Extensions |
+------+-------+ +------+-------+ +------+-------+
Augments Augments Augments
+------+-----------------+-------+ +------+-------+ +--------------+
| Standard | | Vendor | | User |
| Models | | Models | | Models |
+--------------------------------+ +--------------+ +--------------+
Figure 2: YANG Module Types
3.1. Standard YANG Modules
Standard YANG Modules are published by standards-defining
organizations (SDOs). While there is no formal definition of what organizations (SDOs). While there is no formal definition of what
construes an SDO, a common feature is that they publish construes an SDO, a common feature is that they publish
specifications along specific processes with content that reflects specifications along specific processes with content that reflects
some sort of membership consensus. The specifications are developed some sort of membership consensus. The specifications are developed
for wide use among the membership or for audiences beyond that. for wide use among the membership or for audiences beyond that.
The lifecycle of these models is driven by the editing cycle of the The lifecycle of these modules is driven by the editing cycle of the
specification and not tied to a specific implementation. specification and not tied to a specific implementation.
Examples of SDOs in the networking industry are the IETF, the IEEE Examples of SDOs in the networking industry are the IETF, the IEEE
and the MEF. (Institute of Electrical and Electronics Engineers) and the MEF.
3.2. Vendor-specific YANG Models and Extensions 3.2. Vendor-specific YANG Modules and Extensions
Vendor-specific YANG models are developed by organizations with the Vendor-specific YANG modules are developed by organizations with the
intent to support a specific set of implementations under control of intent to support a specific set of implementations under control of
that organization. The intent of these models range from providing that organization. For example vendors of virtual or physical
openly published YANG models that may eventually be contributed back equipment, industry consortia, and opensource projects. The intent
to, or adopted by an SDO, to strictly internal YANG models not of these modules range from providing openly published YANG modules
intended for external consumption. that may eventually be contributed back to, or adopted by an SDO, to
strictly internal YANG modules not intended for external consumption.
The lifecycle of these models are generally aligned with the release The lifecycle of these modules are generally aligned with the release
cycle of the product or open source software project deliverables. cycle of the product or open source software project deliverables.
It is worth noting that there is an increasing amount of interaction It is worth noting that there is an increasing amount of interaction
between open source projects and SDOs in the networking industry. between open source projects and SDOs in the networking industry.
This includes open source projects implementing published standards This includes open source projects implementing published standards
as well as open source projects contributing content to SDO as well as open source projects contributing content to SDO
processes. processes.
Vendors also develop Vendor-specific Extensions to standard models Vendors also develop Vendor-specific Extensions to standard modules
using YANG constructs for extending data definitions of previously using YANG constructs for extending data definitions of previously
published models. This is done using the 'augment' statement that published modules. This is done using the 'augment' statement that
allows locally defined data trees to be augmented into locations in allows locally defined data trees to be augmented into locations in
externally defined data trees. externally defined data trees.
Vendors use this to extend standard data models to cover the full Vendors use this to extend standard modules to cover the full scope
scope of features in implementations, which commonly is broader than of features in implementations, which commonly is broader than what
what is covered by the standard model. is covered by the standard module.
3.3. User-specific YANG Models and Extensions 3.3. User-specific YANG Modules and Extensions
User-specific YANG models are developed by organizations that operate User-specific YANG modules are developed by organizations that
YANG-based infrastructure including devices and orchestrators. The operate YANG-based infrastructure including devices and
intent of these models is to express the specific needs for a certain orchestrators. For example, network administrators in enterprises,
implementation, above and beyond what is provided by vendors. or operators service providers. The intent of these modules is to
express the specific needs for a certain implementation, above and
beyond what is provided by vendors.
This model type obviously requires the infrastructure to support the This module type obviously requires the infrastructure to support the
introduction of user-provided models and extensions. This would introduction of user-provided modules and extensions. This would
include ability to describe the service-to-network decomposition in include ability to describe the service-to-network decomposition in
orchestrators and the model to configuration decomposition in orchestrators and the module to configuration decomposition in
devices. devices.
The lifecycle of these models are generally aligned with the change The lifecycle of these modules are generally aligned with the change
cadence of the infrastructure. cadence of the infrastructure.
3.4. Adding Models to Catalogs 4. Adding The Classification Type to YANG Module Catalogs
The suggested classification in this document supports the creation The suggested classification in this document would be an useful
of catalogs, such as proposed in information in a catalog of YANG modules. Such catalog allows for
[I-D.openconfig-netmod-model-catalog]. Such catalogs allows for easy easy lookup and reusability of YANG modules. Practically, the YANG
lookup and reusability of YANG models. SDO-classified models also module classification type would be an additional leaf to YANG module
provide an educational resource providing architectural guidelines specified in [I-D.openconfig-netmod-model-catalog]:
for model development, based on a membership reviewn and consensus.
3.5. Security Considerations leaf module-class{
type enum {
service
device
notApplicable
}
description
"Categorization of the YANG module based on
draft-ietf-netmod-yang-model-classification.";
}
At this stage, authors of the draft didn't look into security Note: this leaf should actually be moved to
considerations. [I-D.openconfig-netmod-model-catalog]. Note2: since a YANG module
can belong to both service and device, the ENUM is not appropriate.
A extensible list of module type is more appropriate.
3.6. IANA Considerations Indeed, without inspecting the YANG module itself, it's difficult to
determine whether its type is a network service or a network element.
The YANG module name might provide some useful information but is not
a definite answer.
This document requests no action by IANA. 5. Security Considerations
3.7. Acknowledgements This document doesn't have any Security Considerations".
6. IANA Considerations
This document has no IANA actions.
7. Acknowledgements
Thanks to David Ball and David Hansford for feedback and suggestions. Thanks to David Ball and David Hansford for feedback and suggestions.
3.8. Change log [RFC Editor: Please remove] 8. Change log [RFC Editor: Please remove]
version 00: Renamed and small fixes based on WG feedback. version 00: Renamed and small fixes based on WG feedback.
version 01: Language fixes, collapsing of vendor models and version 01: Language fixes, collapsing of vendor data models and
extensions, and the introduction of user models and extensions. extensions, and the introduction of user data models and extensions.
version 02: Added two sections, Model Catalog and Benefits of model version 02: Updated the YANG Module Catalog section, terminology
classification. alignment (YANG data model versus YANG module), epxlain better the
distinction between the Network Element and Service YANG data models
even if sometimes there are grey areas, editorial pass. Changed the
use of the term 'model' to 'module' to be better aligned with
RFC6020.
4. References 9. References
4.1. Normative References 9.1. Normative References
[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,
<http://www.rfc-editor.org/info/rfc6020>. <http://www.rfc-editor.org/info/rfc6020>.
4.2. Informative References 9.2. Informative References
[I-D.ietf-netmod-acl-model] [I-D.ietf-netmod-acl-model]
Bogdanovic, D., Koushik, K., Huang, L., and D. Blair, Bogdanovic, D., Koushik, K., Huang, L., and D. Blair,
"Network Access Control List (ACL) YANG Data Model", "Network Access Control List (ACL) YANG Data Model",
draft-ietf-netmod-acl-model-07 (work in progress), March draft-ietf-netmod-acl-model-07 (work in progress), March
2016. 2016.
[I-D.ietf-netmod-rfc6020bis]
Bjorklund, M., "The YANG 1.1 Data Modeling Language",
draft-ietf-netmod-rfc6020bis-14 (work in progress), June
2016.
[I-D.ietf-ospf-yang] [I-D.ietf-ospf-yang]
Yeung, D., Qu, Y., Zhang, J., Bogdanovic, D., and K. Yeung, D., Qu, Y., Zhang, Z., Bogdanovic, D., and K.
Koushik, "Yang Data Model for OSPF Protocol", draft-ietf- Koushik, "Yang Data Model for OSPF Protocol", draft-ietf-
ospf-yang-04 (work in progress), March 2016. ospf-yang-04 (work in progress), March 2016.
[I-D.openconfig-netmod-model-catalog] [I-D.openconfig-netmod-model-catalog]
D'Souza, K., Shaikh, A., and R. Shakir, "Catalog and D'Souza, K., Shaikh, A., and R. Shakir, "Catalog and
registry for YANG models", draft-openconfig-netmod-model- registry for YANG models", draft-openconfig-netmod-model-
catalog-00 (work in progress), October 2015. catalog-00 (work in progress), October 2015.
[RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed., [RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,
and A. Bierman, Ed., "Network Configuration Protocol and A. Bierman, Ed., "Network Configuration Protocol
skipping to change at page 9, line 31 skipping to change at page 12, line 12
<https://www.ietf.org/iesg/statement/writable-mib- <https://www.ietf.org/iesg/statement/writable-mib-
module.html>. module.html>.
[YANG-Data-Model-for-L3VPN-service-delivery] [YANG-Data-Model-for-L3VPN-service-delivery]
"YANG Data Model for L3VPN service delivery", "YANG Data Model for L3VPN service delivery",
<https://tools.ietf.org/id/draft-l3vpn-service-yang>. <https://tools.ietf.org/id/draft-l3vpn-service-yang>.
Authors' Addresses Authors' Addresses
Dean Bogdanovic Dean Bogdanovic
Volta Networks, Inc.
Email: ivandean@gmail.com Email: dean@voltanet.io
Benoit Claise Benoit Claise
Cisco Systems, Inc. Cisco Systems, Inc.
De Kleetlaan 6a b1
1831 Diegem
Belgium
Phone: +32 2 704 5622
Email: bclaise@cisco.com Email: bclaise@cisco.com
Carl Moberg Carl Moberg
Cisco Systems, Inc. Cisco Systems, Inc.
Email: camoberg@cisco.com Email: camoberg@cisco.com
 End of changes. 80 change blocks. 
159 lines changed or deleted 276 lines changed or added

This html diff was produced by rfcdiff 1.45. The latest version is available from http://tools.ietf.org/tools/rfcdiff/