Networking Working Group Q. Wu
Internet-Draft Huawei
Intended status: Informational M. Boucadair
Expires: December 21, 2019 Orange
Y. Lee
Futurewei
June 19, 2019
A Framework for Automating Service and Network Management with YANG
draft-wu-model-driven-management-virtualization-04
Abstract
Model-driven service and network management provides a programmatic
and standard-based approach for representing (virtual) services or
networks and configuration to the network device that are used to
build and deliver the service. Models can be used at various phases
of service and network management life cycle such as service
instantiation, service provisionning, optimization, monitoring, and
diagnostic. Also, models can be designed to automate network
management and provide closed-loop control for the sake of adaptive
and deterministic service creation, delivery, and maintenance.
This document provides a framework that describes and discusses an
architecture for service and network management automation with YANG
modeling technologies. An applicability of YANG data models to
automation of virtualized network service is also investigated.
The document aims to exemplify an approach to illustrate the journey
from technology-agnostic services to technology-specific actions.
Status of This Memo
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provisions of BCP 78 and BCP 79.
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Task Force (IETF). Note that other groups may also distribute
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material or to cite them other than as "work in progress."
This Internet-Draft will expire on December 21, 2019.
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Copyright Notice
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. IETF YANG Modules: An Overview . . . . . . . . . . . . . . . 4
2.1. Network Service and Resource Models . . . . . . . . . . . 5
2.1.1. Network Service Models: Definition and Samples . . . 6
2.1.2. Network Resource Models . . . . . . . . . . . . . . . 7
2.2. Network Element Models . . . . . . . . . . . . . . . . . 10
2.2.1. Model Composition . . . . . . . . . . . . . . . . . . 11
2.2.2. Protocol/Function Configuration Models . . . . . . . 12
3. Architectural Concepts . . . . . . . . . . . . . . . . . . . 15
3.1. Data Models: Layering and Representation . . . . . . . . 15
3.2. Service Activation, Provision, and Invocation Automation 15
3.3. Service Enforcement Automation . . . . . . . . . . . . . 16
3.4. Modules Decomposition and Composition . . . . . . . . . . 16
4. Architecture Overview . . . . . . . . . . . . . . . . . . . . 17
4.1. End-to-End Service Delivery and Service Assurance
Procedure . . . . . . . . . . . . . . . . . . . . . . . . 17
4.1.1. Resource Collection and Abstraction (a) . . . . . . . 17
4.1.2. Service Exposure & Abstraction (b) . . . . . . . . . 18
4.1.3. IP Service Mapping (c) . . . . . . . . . . . . . . . 19
4.1.4. IP Service Composition (d) . . . . . . . . . . . . . 20
4.1.5. IP Service Provision (e) . . . . . . . . . . . . . . 20
4.1.6. Performance Measurement and Alarm Telemetry (f) . . . 20
4.1.7. IP Service to TE Mapping (g) . . . . . . . . . . . . 20
4.1.8. Path Management (h) . . . . . . . . . . . . . . . . . 21
4.1.9. TE Resource Exposure (i) . . . . . . . . . . . . . . 21
5. Sample Service Coordination via YANG Moodules . . . . . . . . 22
5.1. L3VPN Service Delivery via Coordinated YANG Modules . . . 22
5.2. 5G Transport Service Delivery via Coordinated YANG
Modules . . . . . . . . . . . . . . . . . . . . . . . . . 22
6. Modules Usage in Automated Virtualized Network Environment:
Sample Examples . . . . . . . . . . . . . . . . . . . . . . . 24
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6.1. Network-initiated Resource Creation . . . . . . . . . . . 24
6.2. Customer-initiated Dynamic Resource Creation . . . . . . 26
7. Security Considerations . . . . . . . . . . . . . . . . . . . 28
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 28
9. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 29
10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 29
11. Informative References . . . . . . . . . . . . . . . . . . . 29
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 37
1. Introduction
The service management system usually comprises service activation/
provision and service enforcement. Traditional service delivery work
flow process, from customer order to the actual service provision,
typically involves input data sequentially into multiple OSS/BSS
applications managed by different departments. Many of these
applications are custom built over the years and operating in a silo
mode. The lack of standard data input/output also causes many
challenges in system integration and results in manual data entry.
Secondly, traditional service fulfillment lack a programmatic and
standards-based way of writing configurations to any network device
and has slow response to the network changes and doesn't provide real
time monitoring capability in high frequency and in high throughput
on the current state of networking. Therefore, model-driven network
management becomes crucial to address these challenges.
For years, the IETF has been driving the industry transition from an
overloaded Software Defined Networking (SDN) buzzword to focus on
specific areas such as modeling-driven network management. [RFC7149]
provides a first tentative to rationalize that space by identifying
concrete technical domains that need to be considered and for which
solutions can be provided:
o Techniques for the dynamic discovery of topology, devices, and
capabilities, along with relevant information and data models that
are meant to precisely document such topology, devices, and their
capabilities.
o Techniques for exposing network services [RFC8309] and their
characteristics.
o Techniques used by service-requirement-derived dynamic resource
allocation and policy enforcement schemes, so that networks can be
programmed accordingly.
o Dynamic feedback mechanisms that are meant to assess how
efficiently a given policy (or a set thereof) is enforced from a
service fulfillment and assurance perspective.
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Models are key for each of these technical items. Automation is an
important step to improve the agility of network operations and
infrastructure.
In the later development, as described in [RFC8199], YANG module
developers have taken both top-down and bottom-up approaches to
develop modules and establish mapping between network technology and
customer requirements on the top or abstracting common construct from
various network technologies. At the time of writing this document
(2019), we see the large number of data models including
configuration models and service models developed or under
development in IETF covering much of networking protocols and
techniques. In addition, how these models work together to fully
configure a device, manage a set of devices involved in a service, or
even provide a service aren't developed yet in IETF.
This document takes both bottom up approach and top down approach to
provide an architectural framework for network management automation,
with a focus on network virtualization environment.
This document also describes specific YANG modules needed to realize
connectivity services and investigates how top down built model
(e.g., customer-facing data models) interact with bottom up built
model (network resource-facing data models) in the context of service
delivery and assurance.
The document identifies a comprehensive list of modules to exemplify
the proposed approach, but the document does not claim to be
exhaustive.
It is not the intent of this document to provide an inventory of
tools and mechanisms used in specific network and service management
domains; such inventory can be found in documents such as [RFC7276].
2. IETF YANG Modules: An Overview
Figure 1 provides an overview of various macro-functional blocks to
which belong the various IETF-defined modules.
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<<Network Service and Resource Models>>
+-----------------------------------------------------------------------+
| << Network Service Models>> |
| +----------------+ +----------------+ +-------------+ +-------------+ |
| | L3SM | | L2SM | | TEAS VN | | L1CSM | |
| | Service Model | | Service Model | |Service Model| |Service Model| |
| +----------------+ +----------------+ +-------------+ +-------------+ |
|------------------------------------------------------------------- |
| << Network Resource Models >> |
| +------------+ +-------+ +----------------+ +------------+ |
| |Network Topo| | Tunnel| |Path Computation| |FM/PM/Alarm | |
| | Models | | Models| | API Models | | OAM Models| |
| +------------+ +-------+ +----------------+ +------------+ |
+-----------------------------------------------------------------------+
--------------------------------------------------------------------
<Network Element Models>>
+-----------------------------------------------------------------------+
| <<Composition Models>> |
| +-------------+ +---------------+ +----------------+ |
| |Device Model | |Logical Network| |Network Instance| |
| | | |Element Model | | Model | |
| +-------------+ +---------------+ +----------------+ |
|---------------------------------------------------------------------- |
| << Component Models>> |
|+---------++---------++---------++----------++---------++---------+ |
|| || || ||Common || || OAM: | |
|| Routing ||Transport|| Policy ||(interface||Multicast|| | |
||(e.g.,BGP||(e.g., ||(e.g, ACL||multicast || (IGMP ||FM,PM, | |
|| OSPF) || MPLS) || QoS) || IP, ... )|| MLD,...)||Alarm | ...|
|+---------++---------++---------++----------++---------++---------+ |
+-----------------------------------------------------------------------+
Figure 1: An overview of IETF YANG Modules
2.1. Network Service and Resource Models
Service and Network Resource modules define what the
"service"/"resource" is. These modules can be classified into two
categories:
1. Network Service Models (Section 2.1.1)
2. Network Resource Models (Section 2.1.2)
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2.1.1. Network Service Models: Definition and Samples
As described in [RFC8309], the service is some form of connectivity
between customer sites and the Internet and/or between customer sites
across the network operator's network and across the Internet. More
concretely, an IP connectivity service can be defined as the IP
transfer capability characterized by a (Source Nets, Destination
Nets, Guarantees, Scope) tuple where "Source Nets" is a group of
unicast IP addresses, "Destination Nets" is a group of IP unicast
and/or multicast addresses, and "Guarantees" reflects the guarantees
(expressed in terms of Quality Of Service (QoS), performance, and
availability, for example) to properly forward traffic to the said
"Destination" [RFC7297].
For example,
o L3SM model [RFC8299] defines the L3VPN service ordered by a
customer from a network operator.
o L2SM model [RFC8466] defines the L2VPN service ordered by a
customer from a network operator.
o L1CSM model [I-D.ietf-ccamp-l1csm-yang] defines a YANG module for
Layer 1 Connectivity Service Model (L1CSM).
o TEAS VN model [I-D.ietf-teas-actn-vn-yang] defines a YANG module
for the Abstraction and Control of Traffic Engineered (TE)
networks (ACTN) Virtual Network Service (VNS) operation. Unlike
L3SM model, ACTN model can also be used as operator-facing model,
e.g., establish interconnections between L3VPN sites across
multiple ASes.
o [I-D.ietf-teas-te-service-mapping-yang] defines a YANG module to
map service model (e.g., L3SM) and Traffic Engineering model
(e.g., TE Tunnel or the ACTN model). This model is applicable to
the operation's need for a control and management of VPN services
with TE tunnel support and principally used to allow monitoring
and diagnostic of the management systems to assess how the service
requests are mapped onto underlying network resources and TE
models.
o Composed VPN model [I-D.evenwu-opsawg-yang-composed-vpn] defines a
YANG module that can be used by a network operator to configure a
VPN service in multiple administrative domain environment
consisting of L2VPN or L3VPN or a mixture of the two. This model
provides an abstracted view of VPN service configuration
components at different layer.
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2.1.2. Network Resource Models
Figure 2 depicts a set of Network resource YANG modules such as
topology models or tunnel models:
| |
Topo YANG modules | Tunnel YANG modules |Resource NM Tool
------------------------------------------------|-- ------------
+------------+ | |
|Network Top | | +------+ +-----------+ | +-------+
| Model | | |Other | | TE Tunnel | | | LIME |
+----+-------+ | |Tunnel| +------+----+ | | Model |
| +--------+ | +------+ | | |/PM/FM |
|---+Svc Topo| | +--------+-+--------+ |Model |
| +--------+ | +----+---+ +---+----+ +-+-----+ +-------+
| +--------+ | |MPLS-TE | |RSVP-TE | |SR TE | +--------+
|---+L2 Topo | | | Tunnel | | Tunnel | |Tunnel | | Alarm |
| +--------+ | +--------+ +--------+ +-------+ | Model |
| +--------+ | +--------+
|---+TE Topo | | +-----------+
| +--------+ | |Path |
| +--------+ | |Computation|
+---+L3 Topo | |API Model |
+----|---+ +-----------+
+---------+---------+
| | |
+---|---+ +--|---+ +---|-+
|SR Topo| |SR TE | |L3 TE|
| Model | | Topo | |Topo |
+-------+ +------+ +-----+
Figure 2: Sample Resource Facing Network Models
Topology YANG modules:
o Network Topology Models: [RFC8345] defines a base model for
network topology and inventories. Network topology data include
link resource, node resource, and terminate-point resources.
o TE Topology Models: [I.D-ietf-teas-yang-te-topo] defines a data
model for representing and manipulating TE topologies.
This module is extended from network topology model defined in
[RFC8345] with TE topologies specifics. This model contains
technology agnostic TE Topology building blocks that can be
augmented and used by other technology-specific TE Topology
models.
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o L3 Topology Models
[RFC8346] defines a data model for representing and manipulating
L3 Topologies. This model is extended from the network topology
model defined in [RFC8345] with L3 topologies specifics.
o L2 Topology Models
[I.D-ietf-i2rs-yang-l2-topology] defines a data model for
representing and manipulating L2 Topologies. This model is
extended from the network topology model defined in [RFC8345] with
L2 topologies specifics.
o L3 TE Topology Models
When traffic engineering is enabled on a layer 3 network topology,
there will be a corresponding TE topology. [I.D-ietf-teas-yang-
l3-te-topo] defines data models for layer 3 traffic engineering
topologies. Two data models are defined, one is layer 3 TE
topology model, the other is packet switching TE topology model.
Layer 3 TE topology model is extended from Layer 3 topology model.
Packet switching TE topology model is extended from TE topology
model.
o SR TE Topology Models
[I-D.ietf-teas-yang-sr-te-topo] defines a YANG module for Segment
Routing (SR) topology and Segment Routing (SR) traffic engineering
(TE) topology. Two models are defined, one is SR topology model,
the other is SR TE topology model, SR topology model is extended
from L3 Topology model. SR TE topology model is extended from
both SR Topology model and L3 TE topology model.
o SF Aware TE Topology YANG module
[I-D. ietf-teas-sf-aware-topo-model] defines a YANG module for TE
network topologies that are network service and function aware.
o Optical Transport Topology Models:
* OTN Transport Topology Model: [I-D.ietf-ccamp-otn-topo-yang]
defines a YANG module to describe the topologies of an Optical
Transport Network (OTN).
* WSON Transport Topology Model: [I-D.ietf-ccamp-wson-yang]
defines a YANG module for the routing and wavelength assignment
(RWA) Traffic Engineering (TE) topology in wavelength switched
optical networks (WSONs).
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* Flex-Grid Transport Topology Model: [I-D.ietf-ccamp-flexigrid-
yang] defines a YANG module for flexi-grid objects in the
dynamic optical network, including the nodes, transponders and
links between them, as well as how such links interconnect
nodes and transponders.
Tunnel YANG modules:
o Tunnel identities [I-D.ietf-softwire-iftunnel] to ease
manipulating extensions to specific tunnels.
o TE Tunnel Model
[I.D-ietf-teas-yang-te] defines a YANG module for the
configuration and management of TE interfaces, tunnels and LSPs.
o SR TE Tunnel Model
[I.D-ietf-teas-yang-te] augments the TE generic and MPLS-TE
model(s) and defines a YANG module for Segment Routing (SR) TE
specific data.
o MPLS TE Model
[I.D-ietf-teas-yang-te] augments the TE generic and MPLS-TE
model(s) and defines a YANG module for MPLS TE configurations,
state, RPC and notifications.
o RSVP-TE MPLS Model
[I.D-ietf-teas-yang-rsvp-te] augments the RSVP-TE generic module
with parameters to configure and manage signaling of MPLS RSVP-TE
LSPs.
o Optical Transport Tunnel Models:
* Flexigrid Media Channel Tunnel Models: [I-D.ccamp-flexigrid-
media-channel-yang] defines a YANG module for the flexi-grid
media-channel. This YANG module defines the whole path from a
source transponder or node to the destination through a number
of intermediate nodes in the flexi-grid network.
* WSON Tunnel Model: [I-D.ccamp-wson-tunnel-model] defines a YANG
module for WSON tunnel model.
* OTN Tunnel Model: [I-D. ietf-ccamp-otn-tunnel-model]defines a
YANG module for OTN tunnel Model.
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Resource NM Tool Models:
o Path Computation API Model
[I.D-ietf-teas-path-computation] YANG module for a stateless RPC
which complements the stateful solution defined in [I.D-ietf-teas-
yang-te].
o OAM Models (including Fault Management (FM) and Performance
Monitoring)
[RFC8532] defines a base YANG module for the management of OAM
protocols that use Connectionless Communications. [RFC8533]
defines a retrieval method YANG module for connectionless OAM
protocols. [RFC8531] defines a base YANG module for connection
oriented OAM protocols. These three models are intended to
provide consistent reporting, configuration and representation for
connection-less OAM and Connection oriented OAM separately.
Alarm monitoring is a fundamental part of monitoring the network.
Raw alarms from devices do not always tell the status of the
network services or necessarily point to the root cause. [I.D-
ietf-ccamp-alarm-module]defines a YANG module for alarm
management.
o Generic Policy Model
The Simplified Use of Policy Abstractions (SUPA) policy-based
management framework [RFC8328] defines base YANG modules to encode
policy. These models point to device-, technology-, and service-
specific YANG modules developed elsewhere. Policy rules within an
operator's environment can be used to express high-level, possibly
network-wide, policies to a network management function (within a
controller, an orchestrator, or a network element). The network
management function can then control the configuration and/or
monitoring of network elements and services. This document
describes the SUPA basic framework, its elements, and interfaces.
2.2. Network Element Models
Network Element models (Figure 3) are used to describe how a service
can be implemented by activating and tweaking a set of functions
(enabled in one or multiple devices) that are involved in the service
delivery.
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+----------------+
--|Device Model |
| +----------------+
| +------------------+
+---------------+ | |Logical Network |
| | --| Element Mode |
| Architecture | | +------------------+
| | | +----------------------+
+-------+-------+ --|Network Instance Mode |
| | +----------------------+
| | +-------------------+
| --|Routing Type Model |
| +-------------------+
+-------+----------+----+------+------------+-----------+-------+
| | | | | | |
+-+-+ +---+---+ +--+------+ +-+-+ +-----+---+ +---+-+ |
|ACL| |Routing| |Transport| |OAM| |Multicast| | PM | Others
+---+ |-------+ +---------+ +---+ +---------+ +-----+
| +-------+ +----------+ +-------+ +-----+ +-----+
--|Core | |MPLS Basic| |BFD | |IGMP | |TWAMP|
| |Routing| +----------+ +-------+ |/MLD | +-----+
| +-------+ |MPLS LDP | |LSP Ping +-----+ |OWAMP|
--|BGP | +----------+ +-------+ |PIM | +-----+
| +-------+ |MPLS Static |MPLS-TP| +-----+ |LMAP |
--|ISIS | +----------+ +-------+ |MVPN | +-----+
| +-------+ +-----+
--|OSPF |
| +-------+
--|RIP |
| +-------+
--|VRRP |
| +-------+
--|SR/SRv6|
| +-------+
--|ISIS-SR|
| +-------+
--|OSPF-SR|
+-------+
Figure 3: Network Element Modules
2.2.1. Model Composition
o Device Model
[I.D-ietf-rtgwg-device-model] presents an approach for organizing
YANG modules in a comprehensive logical structure that may be used
to configure and operate network devices. The structure is itself
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represented as an example YANG module, with all of the related
component models logically organized in a way that is
operationally intuitive, but this model is not expected to be
implemented.
o Logical Network Element Model
[RFC8530] defines a logical network element module which can be
used to manage the logical resource partitioning that may be
present on a network device. Examples of common industry terms
for logical resource partitioning are Logical Systems or Logical
Routers.
o Network Instance Model
[RFC8529] defines a network instance module. This module can be
used to manage the virtual resource partitioning that may be
present on a network device. Examples of common industry terms
for virtual resource partitioning are Virtual Routing and
Forwarding (VRF) instances and Virtual Switch Instances (VSIs).
2.2.1.1. Schema Mount
Modularity and extensibility were among the leading design principles
of the YANG data modeling language. As a result, the same YANG
module can be combined with various sets of other modules and thus
form a data model that is tailored to meet the requirements of a
specific use case. [RFC8528] defines a mechanism, denoted schema
mount, that allows for mounting one data model consisting of any
number of YANG modules at a specified location of another (parent)
schema.
That capability does not cover design time.
2.2.2. Protocol/Function Configuration Models
BGP: [I-D.ietf-idr-bgp-yang-model] defines a YANG module for
configuring and managing BGP, including protocol, policy,
and operational aspects based on data center, carrier and
content provider operational requirements.
MPLS: [I-D.ietf-mpls-base-yang] defines a base model for MPLS
which serves as a base framework for configuring and
managing an MPLS switching subsystem. It is expected that
other MPLS technology YANG modules (e.g. MPLS LSP Static,
LDP or RSVP-TE models) will augment the MPLS base YANG
module.
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QoS: [I-D.asechoud-netmod-diffserv-model] describes a YANG
module of Differentiated Services for configuration and
operations.
ACL: Access Control List (ACL) is one of the basic elements
used to configure device forwarding behavior. It is used
in many networking technologies such as Policy Based
Routing, Firewalls, etc. [RFC8519] describes a data model
of Access Control List (ACL) basic building blocks.
NAT: For the sake of network automation and the need for
programming Network Address Translation (NAT) function in
particular, a data model for configuring and managing the
NAT is essential. [RFC8512] defines a YANG module for the
NAT function covering a variety of NAT flavors such as
Network Address Translation from IPv4 to IPv4 (NAT44),
Network Address and Protocol Translation from IPv6 Clients
to IPv4 Servers (NAT64), customer-side translator (CLAT),
Stateless IP/ICMP Translation (SIIT), Explicit Address
Mappings (EAM) for SIIT, IPv6-to-IPv6 Network Prefix
Translation (NPTv6), and Destination NAT. [RFC8513]
specifies a YANG module for the DS-Lite AFTR.
Stateless Address Sharing: [I-D.ietf-softwire-yang] specifies a YANG
module for A+P address sharing, including Lightweight
4over6, Mapping of Address and Port with Encapsulation
(MAP-E), and Mapping of Address and Port using Translation
(MAP-T) softwire mechanisms.
Multicast: [I-D.ietf-pim-yang] defines a YANG module that can be used
to configure and manage Protocol Independent Multicast
(PIM) devices. [I-D.ietf-pim-igmp-mld-yang] defines a
YANG module that can be used to configure and manage
Internet Group Management Protocol (IGMP) and Multicast
Listener Discovery (MLD) devices. [I-D.ietf-pim-igmp-mld-
snooping-yang] defines a YANG module that can be used to
configure and manage Internet Group Management Protocol
(IGMP) and Multicast Listener Discovery (MLD) Snooping
devices.
EVPN: [I-D.ietf-bess-evpn-yang] defines a YANG module for
Ethernet VPN services. The model is agnostic of the
underlay. It apply to MPLS as well as to VxLAN
encapsulation. The model is also agnostic of the services
including E-LAN, E-LINE and E-TREE services. This
document mainly focuses on EVPN and Ethernet-Segment
instance framework.
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L3VPN: [I-D.ietf-bess-l3vpn-yang] defines a YANG module that can
be used to configure and manage BGP L3VPNs [RFC4364]. It
contains VRF specific parameters as well as BGP specific
parameters applicable for L3VPNs.
L2VPN: [I-D.ietf-bess-l2vpn-yang] defines a YANG module for MPLS
based Layer 2 VPN services (L2VPN) [RFC4664] and includes
switching between the local attachment circuits. The
L2VPN model covers point-to-point VPWS and Multipoint VPLS
services. These services use signaling of Pseudowires
across MPLS networks using LDP [RFC8077][RFC4762] or BGP
[RFC4761].
Routing Policy: [I-D.ietf-rtgwg-policy-model] defines a YANG module
for configuring and managing routing policies in a vendor-
neutral way and based on actual operational practice. The
model provides a generic policy framework which can be
augmented with protocol-specific policy configuration.
BFD: [I-D.ietf-bfd-yang]defines a YANG module that can be used
to configure and manage Bidirectional Forwarding Detection
(BFD) [RFC5880]. BFD is a network protocol which is used
for liveness detection of arbitrary paths between systems.
SR/SRv6: [I-D.ietf-spring-sr-yang] a YANG module for segment
routing configuration and operation. [I-D.raza-spring-
srv6-yang] defines a YANG module for Segment Routing IPv6
(SRv6) base. The model serves as a base framework for
configuring and managing an SRv6 subsystem and expected to
be augmented by other SRv6 technology models accordingly.
Core Routing: [RFC8349] defines the core routing data model, which
is intended as a basis for future data model development
covering more-sophisticated routing systems. It is
expected that other Routing technology YANG modules (e.g.,
VRRP, RIP, ISIS, OSPF models) will augment the Core
Routing base YANG module.
PM:
[I.D-ietf-ippm-twamp-yang] defines a data model for client
and server implementations of the Two-Way Active
Measurement Protocol (TWAMP).
[I.D-ietf-ippm-stamp-yang] defines the data model for
implementations of Session-Sender and Session-Reflector
for Simple Two-way Active Measurement Protocol (STAMP)
mode using YANG.
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[RFC8194] defines a data model for Large-Scale Measurement
Platforms (LMAPs).
3. Architectural Concepts
3.1. Data Models: Layering and Representation
As described in [RFC8199], layering of modules allows for better
reusability of lower-layer modules by higher-level modules while
limiting duplication of features across layers.
The IETF has developed a number of service level, network level and
device level modules. Different service level modules may rely on
the same set of network level or device level modules. Service level
modules usually follow top down approach and are mostly customer-
facing models providing a common model construct for higher level
network services, which can be further mapped to network technology-
specific models at lower layer.
Network level modules mostly follow bottom up approach and are mainly
network resource-facing model and describe various aspects of a
network infrastructure, including devices and their subsystems, and
relevant protocols operating at the link and network layers across
multiple devices (e.g., Network topology and TE Tunnel modules).
Device level modules usually follow bottom up approach and are mostly
technology-specific modules used to realize a service.
3.2. Service Activation, Provision, and Invocation Automation
To provide more adaptive (a.k.a., agile) service offerings, Service
level modules can be used by an operator to structure how it
communicates with the customer. One or more monolithic Service
modules can be used in teh context of a composite service activation
requets (e.g., deliver of a caching infrastructure over a VPN). Such
modules are used to feed a decision-making intelligence to rapidly
accommodate customer' needs.
Also, such modules may be used jointly with services that require
dynamic service invocation. A typical example is the service modules
defined by the DOTS WG to dynamically trigger requests to handle DDoS
attacks [I-D.ietf-dots-signal-channel][I-D.ietf-dots-data-channel].
Network level module can be translated from service level module and
used to provision, monitor, instantiate the service and provide life
cycle management of network resource,e.g., expose network resource to
the customer or operators to provide service assurance on network
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service and allow customer or operator to re-optimize the network
based on service requirements described in the service level model.
3.3. Service Enforcement Automation
To provide network management automation, Device level modules
translated from Service level modules or Network level modules can be
used to provision each involved network function/device and operate
the network based on service requirements described in the Service
level module(s).
In addition, the operational state including configuration that is in
effect and status together with statistics should be exposed to upper
layers to provide better network visibility (and assess to what
extent the translated low level modules are honoring the upper level
inputs). Note that it is important is to stitch telemetry data with
configuration data to provide closed loop life cycle management on
the network as a system (including device-centric views).
3.4. Modules Decomposition and Composition
To support top-down service delivery, the service parameters captured
in service level module(s) need to be decomposed into a set of
configuration parameters specific to one or more technologies; these
technology-specific parameters will be grouped together per
technology to define technology-specific device level model or
network level model.
In addition, these technology-specific device level models can be
further assembled together to provision each involved network
function/device or each involved administrative domain to improve
provision efficiency.
For example, IETF rtgwg and netmod working groups have already been
tasked to define model composition mechanism (i.e., Schema Mount
mechanism) and relevant grouping base models such as network instance
model, logical network element model. The model composition
mechanism can be used to assembler different model together while
grouping based models can be used to setup and administrate both
virtualized system and physical system.
IETF also developed YANG catalog tool to manage metadata around IETF-
defined modules; it allows both YANG developers and operators to
discover appropriate YANG modules that may be used to automate
services operations. This YANG catalog tools can be used to select
appropriate models for grouping purposes or even to identify gaps.
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4. Architecture Overview
The architectural considerations and conclusions described in the
previous section lead to the architecture described in this section
and illustrated in Figure 4.
The interfaces and interactions shown in the figure and labeled (a)
through (j) are further described in Section 4.1.
+-----------------+ ----------------
|Service Requester| Service Level|
+-----------------+ |
+-------------|--------------------------------------------------+ |
| +--------V---------+ +------------+ | |
| | Service Exposure |----------------- IP Service | | |
| +-------(b)--------+ | Mapping | | |
| | +--(c)-|-----+ | |
| | | ----------------
| |---------->|<----------------+ | Network Level|
| | +--------V---------+ | | | |
| | | IP Service to TE | +------->|<-----------+ | |
| | | Mapping | | | | | | |
| | +-------(f)--------+ | | +------|-----+ | | |
| | | +-----|-----+| | IP Service | +---+--+| |
| | +--------V---------+ |TE Resource|| | Composition| |Alarm/|| |
| | | TE Path | | Exposure || +--(d)-|-----+ | PM || |
| | | Management +----(h)----+| | +-(g) -+| |
| | +-------(e)--------+ | | +------|------+ | |
| | | | | | IP Service | | | |
| | +-----------------+ | | Provision +-----| | |
| | | +-(e)--|------+ | |
| | +-----------++ | |
| | | Resource | | |
| | | Collection | | |
| |------------------------+&Abstraction| | |
| +----(a)-----+ ----------------
+----------------------------------------------------------------+
Figure 4: Service and Network Management Automation with YANG
4.1. End-to-End Service Delivery and Service Assurance Procedure
4.1.1. Resource Collection and Abstraction (a)
Network Resource such as links, nodes, or terminate-point resources
can be collected from the network and aggregated or abstracted to the
management system. Periodic fetching of data is not an adequate
solution for applications requiring frequent or prompt updates of
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network resource. Applying polling-based solutions to retrieve
network resource also imposes a load on networks, devices, and
applications. These limitations can be addressed by including
generic object subscription mechanisms within network elements.
These resources can be modelled using network topology model, L3
topology model, L2 topology model, TE topology model, L3 TE topology
model, SR TE topology models at different layers.
In some cases, there may have multiple overlay topologies built on
top of the same underlay topology, and the underlay topology can be
also built from one or more lower layer underlay topology.
In some cases, there may have multiple overlay topologies built on
top of the same underlay topology, and the underlay topology can be
also built from one or more lower layer underlay topology. The
network resources and management objects in these multi-layer
topologies are not recommended to be exposed to customers who (will)
order the service from the management system, instead it will be
exposed to the management system for IP service mapping and TE path
Management.
The abstract view is likely to be technology-agnostic.
4.1.2. Service Exposure & Abstraction (b)
Service exposure & abstraction is used to capture services offered to
customers.
Service abstraction can be used by a customer to request a service
(ordering and order handling). One typical example is that a
customer can use L3SM service model to request L3VPN service by
providing the abstract technical characterization of the intended
service. Such L3VPN service describes various aspects of network
infrastructure, including devices and their subsystems, and relevant
protocols operating at the link and network layers across multiple
device. The L3SM service model can be used to interact with the
network infrastructure, e.g., configure sites, decide QoS parameters
to be applied to end to end connectivity between VPN sites, select
PEs, CEs, etc.
Service catalogs can be created to expose the various services and
the information needed to invoke/order a given service.
YANG modules can be grouped into various service bundles; each
service bundle is corresponding to a set of YANG modules that have
been released or published. Then, a mapping can be established
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between service abstraction at higher layer and service bundle or a
set of YANG modules at lower layer.
4.1.3. IP Service Mapping (c)
Service abstraction starts with high-level abstractions exposing the
business capabilities or capturing customer requirements. Then, it
needs to maps them to resource abstraction and specific network
technologies.
Therefore, the interaction between service abstraction in the overlay
and network resource abstraction in the underlay is required. For
example, in the L3SM service model, we describe VPN service topology
including sites relationship, e.g., hub and spoke and any to any,
single homed, dual-homed, multi-homed relation between PEs and CEs,
but we don't know how this service topology can be mapped into
underlying network topology. For detailed interaction, please refer
to Section 4.1.8
In addition, there is a need to decide on a mapping between service
abstraction and underlying specific network technologies. Take L3SM
service model as an example, to realize L3VPN service, we need to map
L3SM service view defined in Service model into detailed
configuration view defined by specific configuration models for
network elements, these configuration models include:
o VRF definition, including VPN Policy expression
o Physical Interface
o IP layer (IPv4, IPv6).
o QoS features such as classification, profiles, etc.
o Routing protocols: support of configuration of all protocols
listed in the document, as well as routing policies associated
with those protocols.
o Multicast Support
o NAT or address sharing
o Security functions
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4.1.4. IP Service Composition (d)
These detailed configuration models are further assembled together
into service bundle described inFigure 3 using, e.g., device model,
logical network element model or network instance model defined in
[I.D-ietf-rtgwg-device-model] [RFC8530] [RFC8529] and provide the
association between an interface and its associated LNE and NI and
populate them into appropriate devices(e.g., PE and CE).
4.1.5. IP Service Provision (e)
IP Service Provision is used to provision network infrastructure
using various configuration models, e.g., use network element models
such as BGP, ACL, QoS, Interface model, Network instance models to
configure PE and CE device within the site. BGP Policy model is used
to establish VPN membership between sites and VPN Service Topology.
Traditionally, "push" service element configuration model one by one
to the network device and provide association between an interface
and each service element configuration model is not efficient.
To automate configuration of the service elements, we first assemble
all related network elements models into logical network element
model defined in [RFC8530] and then establish association with an
interface and a set of network element configurations.
In addition, IP Service Provision can be used to setup tunnels
between sites and setup tunnels between PE and CE within the site
when tunnels related configuration parameters can be generated from
service abstraction. However when tunnels related configuration
parameters can not be generated from service abstraction, IP Service
to TE Mapping procedure is required.
4.1.6. Performance Measurement and Alarm Telemetry (f)
Once the tunnel is setup, PM and Warning information per tunnel or
per link based on network topology can be collected and report to the
management system. This information can be used to optimize the
network or provide troubleshooting support.
4.1.7. IP Service to TE Mapping (g)
Take L3VPN service model as an example, the management system will
use L3SM service model to determine where to connect each site-
network-access of a particular site to the provider network (e.g.,
PE, aggregation switch). L3SM Service model proposes parameters and
constraints that can influence the meshing of the site-network-
access.
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Nodes used to connect a site may be captured in relevant clauses of a
service exposure model (e.g., Customer Nodes Map [RFC7297]).
When Site location is determined, PE and CE device location will be
selected. Then we can replace parameters and constraints that can
influence the meshing of the site-network-access with specified PE
and CE device information associated with site-network-access and
generate resource facing VN Overlay Resource model. One example of
resource facing VN Overlay Resource model is TEAS VN Service Model
[I-D.ietf-teas-actn-vn-yang].
This VN Overlay Resource model can be used to calculate node and link
resource to Meet service requirements based on Network Topology
models collected at step (a).
4.1.8. Path Management (h)
Path Management includes Path computation and Path setup. For
example, we can translate L3SM service model into resource facing VN
Model, with selected PE and CE in each site, we can calculate point
to point or multipoint end to end path between sites based on VN
Overlay Resource Model.
After identifying node and link resources required to meet service
requirements, the mapping between overlay topology and underlay
topology can be established, e.g., establish an association between
VPN service topology defined in customer facing model and underlying
network topology defined in the TE topology model (e.g., one overlay
node is supported by multiple underlay nodes, one overlay link is
supported by multiple underlay nodes) and generate end to end VN
topology.
4.1.9. TE Resource Exposure (i)
When tunnels related configuration parameters can not be generated
from service abstraction, IP Service to TE Mapping procedure can be
used to generate TE Resource Exposure view, this TE resource Exposure
view can be modeled as resource facing VN model which is translated
and instantiated from L3SM model and manage TE resource based on path
management information and PM and alarm telemetry information.
Operators may use this dedicated TE resource Exposure view to
dynamically capture the overall network status and topology to:
o Perform all the requested recovery operations upon detecting
network failures affecting the network service.
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o Adjust resource distribution and update to end to end Service
topology models
o Provide resource scheduling to better guarantee services for
customers and to improve the efficiency of network resource usage.
5. Sample Service Coordination via YANG Moodules
5.1. L3VPN Service Delivery via Coordinated YANG Modules
Take L3VPN service as an example, IETF has already developed L3VPN
service model [RFC8299] which can be used to describe L3VPN service.
To enforce L3VPN service and program the network, a set of network
element models are needed, e.g., BGP model, Network Instance model,
ACL model, Multicast Model, QoS model, or NAT model.
These network element models can be grouped into different release
bundles or feature bundle using Schema Mount technology to meet
different tailored requirements and realize L3VPN service.
To support the creation of logical network elements on a network
device and enable automation of virtualized network, Logical Network
Element (LNE) model can be used to manage its own set of modules such
as ACL, QoS, or Network Instance modules.
5.2. 5G Transport Service Delivery via Coordinated YANG Modules
The overview of network slice structure as defined in the 3GPP 5GS is
shown in Figure 5. The terms are described in specific 3GPP
documents (e.g., [TS.23.501-3GPP] and [TS.28.530-3GPP]).
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<================== E2E-NSI =======================>
: : : : :
: : : : :
<====== RAN-NSSI ======><=TRN-NSSI=><====== CN-NSSI ======>VL[APL]
: : : : : : : : :
: : : : : : : : :
RW[NFs ]<=TRN-NSSI=>[NFs ]<=TRN-NSSI=>[NFs ]<=TRN-NSSI=>[NFs ]VL[APL]
. . . . . . . . . . . . .. . . . . . . . . . . . . ..
.,----. ,----. ,----.. ,----. .,----. ,----. ,----..
UE--|RAN |---| TN |---|RAN |---| TN |---|CN |---| TN |---|CN |--[APL]
.|NFs | `----' |NFs |. `----' .|NFs | `----' |NFs |.
.`----' `----'. .`----' `----'.
. . . . . . . . . . . . .. . . . . . . . . . . . . ..
RW RAN MBH CN DN
*Legends
UE: User Equipment
RAN: Radio Access Network
CN: Core Network
DN: Data Network
TN: Transport Network
MBH: Mobile Backhaul
RW: Radio Wave
NF: Network Function
APL: Application Server
NSI: Network Slice Instance
NSSI: Network Slice Subnet Instance
Figure 5: Overview of Structure of NS in 3GPP 5GS
To support 5G service (e.g., 5G MBB service), L3VPN service model
[RFC8299] and TEAS VN model [I-D. ietf-teas-actn-vn-yang] can be both
provided to describe 5G MBB Transport Service or connectivity
service. L3VPN service model is used to describe end-to-end
connectivity service while TEAS VN model is used to describe TE
connectivity service between VPN sites or between RAN NFs and Core
network NFs.
VN in TEAS VN model and support point-to-point or multipoint-to-
multipoint connectivity service and can be seen as one example of
network slice.
TE Service mapping model can be used to map L3VPN service requests
onto underlying network resource and TE models to get TE network
setup.
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For IP VPN service provision, L3VPN service model is translated into
a set of network element configuration parameters, these
configuration parameters will be bound to different network element
models and group them together to form feature bundle or service
bundle to get L3VPN network setup.
6. Modules Usage in Automated Virtualized Network Environment: Sample
Examples
6.1. Network-initiated Resource Creation
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|(2)
|
V
+-------------------+
| Management System | (3)(4)(5)
+-------------------+
+--------------------------------------------------------+
/ _[CE2] _[CE3] /
/ _/ : \_ _/ : \_ /
/ _/ : \_ _/ : \_ /
/ _/ : \_ _/ : \_ /
/ / : \ / : \ /
/[CE1]_________________[PE1] [PE2]_________________[CE4] /
+---------:--------------:------------:--------------:---+
"Service"
--------------------------------------------------------------------
+---------------------+ +---------------------+"Resource"
/ [Y5]... / / [Z5]______[Z3] /
/ / \ : / / : \_ / : /
/ / \ : / / : \_ / : /
/ / \ : / / : \ / : /
/ [Y4]____[Y1] : / / : [Z2] : /
+------:-------:---:--+ +---:---------:-----:-+ ^
vNet1 : : : : : : vNet2 |
: : : : : : |(1)
: +-------:---:-----:------------:-----:-----+ |
: / [X1]__:___:___________[X2] : / |
:/ / \_ : : _____/ / : / |
: / \_ : _____/ / : /
/: / \: / / : /
/ : / [X5] / : /
/ : / __/ \__ / : /
/ : / ___/ \__ / : /
/ : / ___/ \ / : /
/ [X4]__________________[X3]..: /
+------------------------------------------+
L3 Topology
The following steps are performed to deliver the service within the
network management automation architecture proposed in this document:
o Pre-provision multiple virtualized networks on top of the same
basic network infrastructure based on pre-configured service
requirements and establish resource pool for each virtualized
network and expose to the customer with several service templates
through web portal.
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o Selects and uses one which fulfills most its requirement among the
service templates.
o Create resource facing VN Network based on selected service
template, and calculate the node resource, link resource
corresponding to connectivity between sites.
o Setup tunnels between sites and map them into the selected
virtualized network topology and establish resource facing VN
topology based on TEAS VN model [I-D.ietf-teas-actn-vn-yang] and
TE tunnel based on TE Tunnel model.
The resource facing VN model and corresponding TE Tunnel model can
be further used to notify all the parameter changes and event
related to VN topology or Tunnel. These information can be
further used to adjust network resource distributed in the
network.
The network initiated resource creation is similar to ready made
Network Slice creation pattern discussed in Section 5.1 of [I-
D.homma-slice-provision-models].
6.2. Customer-initiated Dynamic Resource Creation
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|(2)
|
V
+-------------------+
| Management System | (3)(4)(5)
+-------------------+
+--------------------------------------------------------+
/ _[CE2] _[CE3] /
/ _/ : \_ _/ : \_ /
/ _/ : \_ _/ : \_ /
/ _/ : \_ _/ : \_ /
/ / : \ / : \ /
/[CE1]_________________[PE1] [PE2]_________________[CE4] /
+---------:--------------:------------:--------------:---+
"Service"
--------------------------------------------------------------------
"Resource" ^
: |
: : : |(1)
: +-------:---:-----:------------:-----:-----+ |
: / [X1]__:___ __________[X2] / |
:/ / \_ : _____/ / / |
: / \_ : _____/ / /
/: / \: / / /
/ : / [X5] / /
/ : / __/ \__ / /
/ : / ___/ \__ / /
/ : / ___/ \ / /
/ [X4]__________________[X3]. /
+------------------------------------------+
L3 Topology
The following steps are performed to deliver the service within the
network management automation architecture proposed in this document:
o Establish resources pool for the basic common network
infrastructure.
o Request to create two sites based on L3SM Service model with each
having one network access connectivity:
Site A: Network-Access A, Bandwidth=20M, for class "foo",
guaranteed-bw-percent = 10, One-Way-Delay=70 msec
Site B: Network-Access B, Bandwidth=30M, for class "foo1",
guaranteed-bw-percent = 15, One-Way-Delay=60 msec
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o Create a new service topology based on Service Type and service
requirements (e.g., Slice Service Type, Slice location, Number of
Slices, QoS requirements corresponding to network connectivity
within a Slice) defined in L3SM service model.
o Translate L3SM service model into resource facing TEAS VN Model
[I-D.ietf-teas-actn-vn-yang], and calculate the node resource,
link resource corresponding to connectivity between sites or
connectivity between PE and CE within Site in the service topology
based on generated resource facing TEAS VN model.
o Setup tunnels between sites and tunnel between PE and CE within
Site and map them into basic network infrastructure and establish
resource facing VN topology based on TEAS VN model and TE tunnel
based on TE Tunnel model. The resource facing TEAS VN model and
corresponding TE Tunnel model can be used to notify all the
parameter changes and event related to VN topology or Tunnel.
These information can be further used to adjust network resource
distributed within the network.
The customer initiated resource creation is similar to customer made
Network Slice creation pattern discussed in Section 5.2 of [I-
D.homma-slice-provision-models].
7. Security Considerations
Security considerations specific to each of the technologies and
protocols listed in the document are discussed in the specification
documents of each of these techniques.
(Potential) security considerations specific to this document are
listed below:
o Create forwarding loops by mis-configuring the underlying network.
o Leak sensitive information: special care should be considered when
translating between the various layers introduced in the document.
o ...tbc
8. IANA Considerations
There are no IANA requests or assignments included in this document.
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9. Contributors
Shunsuke Homma
Japan
Email: s.homma0718+ietf@gmail.com
10. Acknowledgements
Thanks to Joe Clarck and Greg Mirsky for the review.
11. Informative References
[I-D.arkko-arch-virtualization]
Arkko, J., Tantsura, J., Halpern, J., and B. Varga,
"Considerations on Network Virtualization and Slicing",
draft-arkko-arch-virtualization-01 (work in progress),
March 2018.
[I-D.asechoud-netmod-diffserv-model]
Choudhary, A., Shah, S., Jethanandani, M., Liu, B., and N.
Strahle, "YANG Model for Diffserv", draft-asechoud-netmod-
diffserv-model-03 (work in progress), June 2015.
[I-D.clacla-netmod-model-catalog]
Clarke, J. and B. Claise, "YANG module for
yangcatalog.org", draft-clacla-netmod-model-catalog-03
(work in progress), April 2018.
[I-D.evenwu-opsawg-yang-composed-vpn]
Even, R., Bo, W., Wu, Q., and Y. Cheng, "YANG Data Model
for Composed VPN Service Delivery", draft-evenwu-opsawg-
yang-composed-vpn-03 (work in progress), March 2019.
[I-D.homma-slice-provision-models]
Homma, S., Nishihara, H., Miyasaka, T., Galis, A., OV, V.,
Lopez, D., Contreras, L., Ordonez-Lucena, J., Martinez-
Julia, P., Qiang, L., Rokui, R., Ciavaglia, L., and X.
Foy, "Network Slice Provision Models", draft-homma-slice-
provision-models-00 (work in progress), February 2019.
[I-D.ietf-bess-evpn-yang]
Brissette, P., Shah, H., Hussain, I., Tiruveedhula, K.,
and J. Rabadan, "Yang Data Model for EVPN", draft-ietf-
bess-evpn-yang-07 (work in progress), March 2019.
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[I-D.ietf-bess-l2vpn-yang]
Shah, H., Brissette, P., Chen, I., Hussain, I., Wen, B.,
and K. Tiruveedhula, "YANG Data Model for MPLS-based
L2VPN", draft-ietf-bess-l2vpn-yang-09 (work in progress),
October 2018.
[I-D.ietf-bess-l3vpn-yang]
Jain, D., Patel, K., Brissette, P., Li, Z., Zhuang, S.,
Liu, X., Haas, J., Esale, S., and B. Wen, "Yang Data Model
for BGP/MPLS L3 VPNs", draft-ietf-bess-l3vpn-yang-04 (work
in progress), October 2018.
[I-D.ietf-bfd-yang]
Rahman, R., Zheng, L., Jethanandani, M., Networks, J., and
G. Mirsky, "YANG Data Model for Bidirectional Forwarding
Detection (BFD)", draft-ietf-bfd-yang-17 (work in
progress), August 2018.
[I-D.ietf-ccamp-alarm-module]
Vallin, S. and M. Bjorklund, "YANG Alarm Module", draft-
ietf-ccamp-alarm-module-09 (work in progress), April 2019.
[I-D.ietf-ccamp-flexigrid-media-channel-yang]
Madrid, U., Perdices, D., Lopezalvarez, V., Dios, O.,
King, D., Lee, Y., and G. Galimberti, "YANG data model for
Flexi-Grid media-channels", draft-ietf-ccamp-flexigrid-
media-channel-yang-02 (work in progress), March 2019.
[I-D.ietf-ccamp-flexigrid-yang]
Madrid, U., Perdices, D., Lopezalvarez, V., Dios, O.,
King, D., Lee, Y., and G. Galimberti, "YANG data model for
Flexi-Grid Optical Networks", draft-ietf-ccamp-flexigrid-
yang-03 (work in progress), March 2019.
[I-D.ietf-ccamp-l1csm-yang]
Fioccola, G., Lee, K., Lee, Y., Dhody, D., and D.
Ceccarelli, "A YANG Data Model for L1 Connectivity Service
Model (L1CSM)", draft-ietf-ccamp-l1csm-yang-09 (work in
progress), March 2019.
[I-D.ietf-ccamp-mw-yang]
Ahlberg, J., Ye, M., Li, X., Spreafico, D., and M.
Vaupotic, "A YANG Data Model for Microwave Radio Link",
draft-ietf-ccamp-mw-yang-13 (work in progress), November
2018.
Wu, et al. Expires December 21, 2019 [Page 30]
Internet-Draft Service and Network Management Automation June 2019
[I-D.ietf-ccamp-otn-topo-yang]
Zheng, H., Guo, A., Busi, I., Sharma, A., Liu, X.,
Belotti, S., Xu, Y., Wang, L., and O. Dios, "A YANG Data
Model for Optical Transport Network Topology", draft-ietf-
ccamp-otn-topo-yang-06 (work in progress), February 2019.
[I-D.ietf-ccamp-otn-tunnel-model]
Zheng, H., Guo, A., Busi, I., Sharma, A., Rao, R.,
Belotti, S., Lopezalvarez, V., Li, Y., and Y. Xu, "OTN
Tunnel YANG Model", draft-ietf-ccamp-otn-tunnel-model-06
(work in progress), February 2019.
[I-D.ietf-ccamp-wson-tunnel-model]
Lee, Y., Dhody, D., Guo, A., Lopezalvarez, V., King, D.,
Yoon, B., and R. Vilata, "A Yang Data Model for WSON
Tunnel", draft-ietf-ccamp-wson-tunnel-model-03 (work in
progress), March 2019.
[I-D.ietf-dots-data-channel]
Boucadair, M. and R. K, "Distributed Denial-of-Service
Open Threat Signaling (DOTS) Data Channel Specification",
draft-ietf-dots-data-channel-29 (work in progress), May
2019.
[I-D.ietf-dots-signal-channel]
K, R., Boucadair, M., Patil, P., Mortensen, A., and N.
Teague, "Distributed Denial-of-Service Open Threat
Signaling (DOTS) Signal Channel Specification", draft-
ietf-dots-signal-channel-34 (work in progress), May 2019.
[I-D.ietf-idr-bgp-model]
Jethanandani, M., Patel, K., and S. Hares, "BGP YANG Model
for Service Provider Networks", draft-ietf-idr-bgp-
model-06 (work in progress), June 2019.
[I-D.ietf-ippm-stamp-yang]
Mirsky, G., Xiao, M., and W. Luo, "Simple Two-way Active
Measurement Protocol (STAMP) Data Model", draft-ietf-ippm-
stamp-yang-03 (work in progress), March 2019.
[I-D.ietf-ippm-twamp-yang]
Civil, R., Morton, A., Rahman, R., Jethanandani, M., and
K. Pentikousis, "Two-Way Active Measurement Protocol
(TWAMP) Data Model", draft-ietf-ippm-twamp-yang-13 (work
in progress), July 2018.
Wu, et al. Expires December 21, 2019 [Page 31]
Internet-Draft Service and Network Management Automation June 2019
[I-D.ietf-mpls-base-yang]
Saad, T., Raza, K., Gandhi, R., Liu, X., and V. Beeram, "A
YANG Data Model for MPLS Base", draft-ietf-mpls-base-
yang-10 (work in progress), February 2019.
[I-D.ietf-pim-igmp-mld-snooping-yang]
Zhao, H., Liu, X., Liu, Y., Sivakumar, M., and A. Peter,
"A Yang Data Model for IGMP and MLD Snooping", draft-ietf-
pim-igmp-mld-snooping-yang-08 (work in progress), June
2019.
[I-D.ietf-pim-igmp-mld-yang]
Liu, X., Guo, F., Sivakumar, M., McAllister, P., and A.
Peter, "A YANG Data Model for Internet Group Management
Protocol (IGMP) and Multicast Listener Discovery (MLD)",
draft-ietf-pim-igmp-mld-yang-15 (work in progress), June
2019.
[I-D.ietf-pim-yang]
Liu, X., McAllister, P., Peter, A., Sivakumar, M., Liu,
Y., and f. hu, "A YANG Data Model for Protocol Independent
Multicast (PIM)", draft-ietf-pim-yang-17 (work in
progress), May 2018.
[I-D.ietf-rtgwg-device-model]
Lindem, A., Berger, L., Bogdanovic, D., and C. Hopps,
"Network Device YANG Logical Organization", draft-ietf-
rtgwg-device-model-02 (work in progress), March 2017.
[I-D.ietf-rtgwg-policy-model]
Qu, Y., Tantsura, J., Lindem, A., and X. Liu, "A YANG Data
Model for Routing Policy Management", draft-ietf-rtgwg-
policy-model-06 (work in progress), March 2019.
[I-D.ietf-softwire-iftunnel]
Boucadair, M., Farrer, I., and R. Asati, "Tunnel Interface
Types YANG Module", draft-ietf-softwire-iftunnel-07 (work
in progress), June 2019.
[I-D.ietf-softwire-yang]
Farrer, I. and M. Boucadair, "YANG Modules for IPv4-in-
IPv6 Address plus Port (A+P) Softwires", draft-ietf-
softwire-yang-16 (work in progress), January 2019.
[I-D.ietf-spring-sr-yang]
Litkowski, S., Qu, Y., Lindem, A., Sarkar, P., and J.
Tantsura, "YANG Data Model for Segment Routing", draft-
ietf-spring-sr-yang-12 (work in progress), February 2019.
Wu, et al. Expires December 21, 2019 [Page 32]
Internet-Draft Service and Network Management Automation June 2019
[I-D.ietf-teas-actn-vn-yang]
Lee, Y., Dhody, D., Ceccarelli, D., Bryskin, I., and B.
Yoon, "A Yang Data Model for VN Operation", draft-ietf-
teas-actn-vn-yang-05 (work in progress), June 2019.
[I-D.ietf-teas-sf-aware-topo-model]
Bryskin, I., Liu, X., Lee, Y., Guichard, J., Contreras,
L., Ceccarelli, D., and J. Tantsura, "SF Aware TE Topology
YANG Model", draft-ietf-teas-sf-aware-topo-model-03 (work
in progress), March 2019.
[I-D.ietf-teas-te-service-mapping-yang]
Lee, Y., Dhody, D., Ceccarelli, D., Tantsura, J.,
Fioccola, G., and Q. Wu, "Traffic Engineering and Service
Mapping Yang Model", draft-ietf-teas-te-service-mapping-
yang-01 (work in progress), March 2019.
[I-D.ietf-teas-yang-l3-te-topo]
Liu, X., Bryskin, I., Beeram, V., Saad, T., Shah, H., and
O. Dios, "YANG Data Model for Layer 3 TE Topologies",
draft-ietf-teas-yang-l3-te-topo-04 (work in progress),
March 2019.
[I-D.ietf-teas-yang-path-computation]
Busi, I., Belotti, S., Lopezalvarez, V., Dios, O., Sharma,
A., Shi, Y., Vilata, R., Sethuraman, K., Scharf, M., and
D. Ceccarelli, "Yang model for requesting Path
Computation", draft-ietf-teas-yang-path-computation-05
(work in progress), March 2019.
[I-D.ietf-teas-yang-rsvp-te]
Beeram, V., Saad, T., Gandhi, R., Liu, X., Bryskin, I.,
and H. Shah, "A YANG Data Model for RSVP-TE Protocol",
draft-ietf-teas-yang-rsvp-te-06 (work in progress), April
2019.
[I-D.ietf-teas-yang-sr-te-topo]
Liu, X., Bryskin, I., Beeram, V., Saad, T., Shah, H., and
S. Litkowski, "YANG Data Model for SR and SR TE
Topologies", draft-ietf-teas-yang-sr-te-topo-04 (work in
progress), March 2019.
[I-D.ietf-teas-yang-te]
Saad, T., Gandhi, R., Liu, X., Beeram, V., and I. Bryskin,
"A YANG Data Model for Traffic Engineering Tunnels and
Interfaces", draft-ietf-teas-yang-te-21 (work in
progress), April 2019.
Wu, et al. Expires December 21, 2019 [Page 33]
Internet-Draft Service and Network Management Automation June 2019
[I-D.ietf-teas-yang-te-topo]
Liu, X., Bryskin, I., Beeram, V., Saad, T., Shah, H., and
O. Dios, "YANG Data Model for Traffic Engineering (TE)
Topologies", draft-ietf-teas-yang-te-topo-21 (work in
progress), May 2019.
[RFC4364] Rosen, E. and Y. Rekhter, "BGP/MPLS IP Virtual Private
Networks (VPNs)", RFC 4364, DOI 10.17487/RFC4364, February
2006, <https://www.rfc-editor.org/info/rfc4364>.
[RFC4664] Andersson, L., Ed. and E. Rosen, Ed., "Framework for Layer
2 Virtual Private Networks (L2VPNs)", RFC 4664,
DOI 10.17487/RFC4664, September 2006,
<https://www.rfc-editor.org/info/rfc4664>.
[RFC4761] Kompella, K., Ed. and Y. Rekhter, Ed., "Virtual Private
LAN Service (VPLS) Using BGP for Auto-Discovery and
Signaling", RFC 4761, DOI 10.17487/RFC4761, January 2007,
<https://www.rfc-editor.org/info/rfc4761>.
[RFC4762] Lasserre, M., Ed. and V. Kompella, Ed., "Virtual Private
LAN Service (VPLS) Using Label Distribution Protocol (LDP)
Signaling", RFC 4762, DOI 10.17487/RFC4762, January 2007,
<https://www.rfc-editor.org/info/rfc4762>.
[RFC5880] Katz, D. and D. Ward, "Bidirectional Forwarding Detection
(BFD)", RFC 5880, DOI 10.17487/RFC5880, June 2010,
<https://www.rfc-editor.org/info/rfc5880>.
[RFC7149] Boucadair, M. and C. Jacquenet, "Software-Defined
Networking: A Perspective from within a Service Provider
Environment", RFC 7149, DOI 10.17487/RFC7149, March 2014,
<https://www.rfc-editor.org/info/rfc7149>.
[RFC7276] Mizrahi, T., Sprecher, N., Bellagamba, E., and Y.
Weingarten, "An Overview of Operations, Administration,
and Maintenance (OAM) Tools", RFC 7276,
DOI 10.17487/RFC7276, June 2014,
<https://www.rfc-editor.org/info/rfc7276>.
[RFC7297] Boucadair, M., Jacquenet, C., and N. Wang, "IP
Connectivity Provisioning Profile (CPP)", RFC 7297,
DOI 10.17487/RFC7297, July 2014,
<https://www.rfc-editor.org/info/rfc7297>.
Wu, et al. Expires December 21, 2019 [Page 34]
Internet-Draft Service and Network Management Automation June 2019
[RFC8077] Martini, L., Ed. and G. Heron, Ed., "Pseudowire Setup and
Maintenance Using the Label Distribution Protocol (LDP)",
STD 84, RFC 8077, DOI 10.17487/RFC8077, February 2017,
<https://www.rfc-editor.org/info/rfc8077>.
[RFC8194] Schoenwaelder, J. and V. Bajpai, "A YANG Data Model for
LMAP Measurement Agents", RFC 8194, DOI 10.17487/RFC8194,
August 2017, <https://www.rfc-editor.org/info/rfc8194>.
[RFC8199] Bogdanovic, D., Claise, B., and C. Moberg, "YANG Module
Classification", RFC 8199, DOI 10.17487/RFC8199, July
2017, <https://www.rfc-editor.org/info/rfc8199>.
[RFC8299] Wu, Q., Ed., Litkowski, S., Tomotaki, L., and K. Ogaki,
"YANG Data Model for L3VPN Service Delivery", RFC 8299,
DOI 10.17487/RFC8299, January 2018,
<https://www.rfc-editor.org/info/rfc8299>.
[RFC8309] Wu, Q., Liu, W., and A. Farrel, "Service Models
Explained", RFC 8309, DOI 10.17487/RFC8309, January 2018,
<https://www.rfc-editor.org/info/rfc8309>.
[RFC8328] Liu, W., Xie, C., Strassner, J., Karagiannis, G., Klyus,
M., Bi, J., Cheng, Y., and D. Zhang, "Policy-Based
Management Framework for the Simplified Use of Policy
Abstractions (SUPA)", RFC 8328, DOI 10.17487/RFC8328,
March 2018, <https://www.rfc-editor.org/info/rfc8328>.
[RFC8345] Clemm, A., Medved, J., Varga, R., Bahadur, N.,
Ananthakrishnan, H., and X. Liu, "A YANG Data Model for
Network Topologies", RFC 8345, DOI 10.17487/RFC8345, March
2018, <https://www.rfc-editor.org/info/rfc8345>.
[RFC8346] Clemm, A., Medved, J., Varga, R., Liu, X.,
Ananthakrishnan, H., and N. Bahadur, "A YANG Data Model
for Layer 3 Topologies", RFC 8346, DOI 10.17487/RFC8346,
March 2018, <https://www.rfc-editor.org/info/rfc8346>.
[RFC8349] Lhotka, L., Lindem, A., and Y. Qu, "A YANG Data Model for
Routing Management (NMDA Version)", RFC 8349,
DOI 10.17487/RFC8349, March 2018,
<https://www.rfc-editor.org/info/rfc8349>.
[RFC8466] Wen, B., Fioccola, G., Ed., Xie, C., and L. Jalil, "A YANG
Data Model for Layer 2 Virtual Private Network (L2VPN)
Service Delivery", RFC 8466, DOI 10.17487/RFC8466, October
2018, <https://www.rfc-editor.org/info/rfc8466>.
Wu, et al. Expires December 21, 2019 [Page 35]
Internet-Draft Service and Network Management Automation June 2019
[RFC8512] Boucadair, M., Ed., Sivakumar, S., Jacquenet, C.,
Vinapamula, S., and Q. Wu, "A YANG Module for Network
Address Translation (NAT) and Network Prefix Translation
(NPT)", RFC 8512, DOI 10.17487/RFC8512, January 2019,
<https://www.rfc-editor.org/info/rfc8512>.
[RFC8513] Boucadair, M., Jacquenet, C., and S. Sivakumar, "A YANG
Data Model for Dual-Stack Lite (DS-Lite)", RFC 8513,
DOI 10.17487/RFC8513, January 2019,
<https://www.rfc-editor.org/info/rfc8513>.
[RFC8519] Jethanandani, M., Agarwal, S., Huang, L., and D. Blair,
"YANG Data Model for Network Access Control Lists (ACLs)",
RFC 8519, DOI 10.17487/RFC8519, March 2019,
<https://www.rfc-editor.org/info/rfc8519>.
[RFC8528] Bjorklund, M. and L. Lhotka, "YANG Schema Mount",
RFC 8528, DOI 10.17487/RFC8528, March 2019,
<https://www.rfc-editor.org/info/rfc8528>.
[RFC8529] Berger, L., Hopps, C., Lindem, A., Bogdanovic, D., and X.
Liu, "YANG Data Model for Network Instances", RFC 8529,
DOI 10.17487/RFC8529, March 2019,
<https://www.rfc-editor.org/info/rfc8529>.
[RFC8530] Berger, L., Hopps, C., Lindem, A., Bogdanovic, D., and X.
Liu, "YANG Model for Logical Network Elements", RFC 8530,
DOI 10.17487/RFC8530, March 2019,
<https://www.rfc-editor.org/info/rfc8530>.
[RFC8531] Kumar, D., Wu, Q., and Z. Wang, "Generic YANG Data Model
for Connection-Oriented Operations, Administration, and
Maintenance (OAM) Protocols", RFC 8531,
DOI 10.17487/RFC8531, April 2019,
<https://www.rfc-editor.org/info/rfc8531>.
[RFC8532] Kumar, D., Wang, Z., Wu, Q., Ed., Rahman, R., and S.
Raghavan, "Generic YANG Data Model for the Management of
Operations, Administration, and Maintenance (OAM)
Protocols That Use Connectionless Communications",
RFC 8532, DOI 10.17487/RFC8532, April 2019,
<https://www.rfc-editor.org/info/rfc8532>.
Wu, et al. Expires December 21, 2019 [Page 36]
Internet-Draft Service and Network Management Automation June 2019
[RFC8533] Kumar, D., Wang, M., Wu, Q., Ed., Rahman, R., and S.
Raghavan, "A YANG Data Model for Retrieval Methods for the
Management of Operations, Administration, and Maintenance
(OAM) Protocols That Use Connectionless Communications",
RFC 8533, DOI 10.17487/RFC8533, April 2019,
<https://www.rfc-editor.org/info/rfc8533>.
Authors' Addresses
Qin Wu
Huawei
101 Software Avenue, Yuhua District
Nanjing, Jiangsu 210012
China
Email: bill.wu@huawei.com
Mohamed Boucadair
Orange
Rennes 35000
France
Email: mohamed.boucadair@orange.com
Young Lee
Futurewei
Email: younglee.tx@gmail.com
Wu, et al. Expires December 21, 2019 [Page 37]