IETF Network Slice Topology YANG Data Model
draft-liu-teas-transport-network-slice-yang-10
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| Document | Type | Active Internet-Draft (individual) | |
|---|---|---|---|
| Authors | Xufeng Liu , Jeff Tantsura , Igor Bryskin , Luis M. Contreras , Qin Wu , Sergio Belotti , Reza Rokui , Aihua Guo , Italo Busi | ||
| Last updated | 2024-07-07 | ||
| RFC stream | (None) | ||
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| Yang Validation | 0 errors, 0 warnings | ||
| Additional resources |
Yang catalog entry for ietf-network-slice@2020-11-01.yang
Yang impact analysis for draft-liu-teas-transport-network-slice-yang |
||
| Stream | Stream state | (No stream defined) | |
| Consensus boilerplate | Unknown | ||
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draft-liu-teas-transport-network-slice-yang-10
TEAS Working Group X. Liu
Internet-Draft Alef Edge
Intended status: Standards Track J. Tantsura
Expires: 8 January 2025 Microsoft
I. Bryskin
Individual
L.M. Contreras
Telefonica
Q. Wu
Huawei
S. Belotti
Nokia
R. Rokui
Ciena
A. Guo
Futurewei
I. Busi
Huawei
7 July 2024
IETF Network Slice Topology YANG Data Model
draft-liu-teas-transport-network-slice-yang-10
Abstract
An RFC 9543 network slice customer may utilize intent-based
topologies to express resource reservation intentions within the
provider's network. These customer-defined intent topologies allow
customers to request shared resources for future connections that can
be flexibly allocated and customized. Additionally, they provide an
extensive level of control over underlay service paths within the
network slice.
This document describes a YANG data model for expressing customer
intent topologies which can be used to enhance the RFC 9543 Network
Slice Services in specific use cases, such as Network wholesale
scenarios, where both topology and connectivity intents need to be
expressed.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
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This Internet-Draft will expire on 8 January 2025.
Copyright Notice
Copyright (c) 2024 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents (https://trustee.ietf.org/
license-info) in effect on the date of publication of this document.
Please review these documents carefully, as they describe your rights
and restrictions with respect to this document. Code Components
extracted from this document must include Revised BSD License text as
described in Section 4.e of the Trust Legal Provisions and are
provided without warranty as described in the Revised BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Use Case Applicability . . . . . . . . . . . . . . . . . 5
1.1.1. Use Case 1 : Multi-tenancy in Network Wholesaling . . 5
1.1.2. Use Case 2 : . . . . . . . . . . . . . . . . . . . . 5
1.2. Terminologies and Notations . . . . . . . . . . . . . . . 6
1.3. Tree Diagram . . . . . . . . . . . . . . . . . . . . . . 7
1.4. Prefixes in Data Node Names . . . . . . . . . . . . . . . 7
2. Modeling Considerations . . . . . . . . . . . . . . . . . . . 7
2.1. Relationship with Traffic Engineering (TE)-based
Topology . . . . . . . . . . . . . . . . . . . . . . . . 8
2.2. Relationship with Service Attachment Point (SAP)
Topology . . . . . . . . . . . . . . . . . . . . . . . . 8
2.3. Relationship with ACTN Virtual Network (VN) . . . . . . . 8
2.3.1. Consideration on Reusing ACTN VN for Network
Slicing . . . . . . . . . . . . . . . . . . . . . . . 9
2.4. Data Model Relationship . . . . . . . . . . . . . . . . . 10
3. Model Applicability . . . . . . . . . . . . . . . . . . . . . 11
4. YANG Model Overview . . . . . . . . . . . . . . . . . . . . . 13
5. Model Tree Structure . . . . . . . . . . . . . . . . . . . . 14
5.1. Network Slice Topology Model Tree Structure . . . . . . . 14
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5.2. Network Slice Underlay Path Model Tree Structure . . . . 16
6. YANG Modules . . . . . . . . . . . . . . . . . . . . . . . . 17
6.1. YANG Module for Network Slice Topology . . . . . . . . . 17
6.2. YANG Module for Network Slice Underlay Path . . . . . . . 20
7. Manageability Considerations . . . . . . . . . . . . . . . . 24
8. Security Considerations . . . . . . . . . . . . . . . . . . . 25
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 25
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 26
10.1. Normative References . . . . . . . . . . . . . . . . . . 26
10.2. Informative References . . . . . . . . . . . . . . . . . 27
Appendix A. Acknowledgments . . . . . . . . . . . . . . . . . . 29
Appendix B. Data Tree for the Example in Section 3 . . . . . . . 29
B.1. Native Topology . . . . . . . . . . . . . . . . . . . . . 29
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 36
1. Introduction
Network service providers utilize topologies to convey controlled
information about their networks, such as bandwidth availability and
connectivity, with customers, to facilitates customer service
requests. Customers can also define intent-based topologies to
streamline their internal operations. When requesting provider
support for such custom topologies, they are considered as customer
intent topologies.
In the context of network slicing, customer intent topologies enables
customers to express resource reservation preferences. These
topologies allow flexible configuration and activation of network
slices on demand. By providing full control over resource allocation
timing and methods, customer intent topologies ensure that resources
are consistently available. Moreover, the resources reserved via
customer intent topologies can be shared across network slices
created at different times or between different connectivity
constructs within the same slice. Compared to network slices with
dedicated full-mesh connectivity constructs between endpoints,
network slices utilizing customer intent topologies can reduce
overall resource requirements, offering significant economic benefits
to the customer.
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Consider a hub-and-spoke network slice scenario where multiple
customer spoke sites dynamically connect to a central hub site,
sharing available bandwidth. By designing a customer intent topology
with two virtual nodes - one representing all the spoke sites and the
other representing the hub site - connected via a shared link, we
proactively reserve resources for the shared connection. This
ensures that bandwidth is readily available whenever the customer
requires it. In contrast, achieving equivalent bandwidth assurance
through individual dedicated connectivity constructs would
necessitate creating separate links between each spoke and the hub,
which would lead to substantial bandwidth inefficiency.
Customer intent topology complements connectivity-based network
slicing by providing customers a mechanism to specify additional
underlay service paths to gain extensive control over specific or all
connectivity constructs within the network slice, as outlined in
[RFC9543].
A customer intent topology is defined within the customer's context.
It can include pure customer information or may also refer to network
resources identifiable within the provider's context. There is a
minimum level of a-prior shared knowledge between the customer and
the provider, and this is the same information needed to supported
connectivity-based network slice services as desdribed in [RFC9543].
The provider's responsibility lies in understanding the customer
intent topology request and translating that into suitable
realization within their domain.
This document introduces a YANG data model, based on [RFC7950], for
configuring customer intent topologies. The YANG model extends the
existing data model from [RFC8345], allowing customers to express
desired service-level objectives (SLOs) and service-level
expectations (SLEs) across different elements within the customer
intent topology.
The defined data model serves as an interface between customers and
providers, enabling configurations and state retrievals for network
slicing as a service. Customers can use this model to request or
negotiate the creation of network slice instances. Additionally,
they can incrementally adjust requirements for individual topology
elements within the slice - for instance, adding or removing nodes or
links, updating link bandwidth - and retrieve operational states.
Leveraging other IETF mechanisms and data models, telemetry
information can also be convey to the customer.
The YANG model encompasses constructs that are independent of
specific technologies, accommodating network slicing across diverse
layers (including IP/MPLS, MPLS-TP, OTN, and WDM optical). As a
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result, this model serves as a foundational framework upon which
technology-specific network slicing models - such as
[I-D.ietf-ccamp-yang-otn-slicing] - can be developed.
Section 3 of [I-D.contreras-teas-slice-controller-models] outlines
that the use of customer intent topologies and resource reservation
control is optional within network slicing. These features
complement the data model defined in
[I-D.ietf-teas-ietf-network-slice-nbi-yang].
The YANG data model in this document conforms to the Network
Management Datastore Architecture (NMDA) [RFC8342].
1.1. Use Case Applicability
In Traffic Engineering (TE)-enabled networks like Layer-0/1 transport
(OTN, MW, DWDM), customer intent topology is useful for routing RFC
9543 network slices across varied paths with TE constraints. Thus,
most of the use cases for which this model target are transport
oriented. Nonetheless, it is also relevant to non-transport networks
like IP/MPLS, where customers may use intent topologies to influence
the realization of network slices. These intents help build the
logical view of the desired RFC 9543 Network Slice service (and its
constituent parts), aiding providers in fulfilling slice requests and
defining the service instantiation.
1.1.1. Use Case 1 : Multi-tenancy in Network Wholesaling
A typical use case in which the customer intent topology is essential
is the wholesale multi-tenant case. Here, customer C may acquire a
network slice from provider P and resell sub-slices to other
customers/tenants. The creation of these sub-slices within C's slice
necessitates specifying a topology intent - reflecting the topology
of C's purchased slice - as a key input parameter.
1.1.2. Use Case 2 :
The current expression of slice requests leveraging on
[I-D.draft-ietf-teas-ietf-network-slice-nbi-yang] allows the customer
to request distinct connectivity constructs as part of the same
Network Resource Partition (NRP). The topology provided by the
customer could imply different NRPs, instead.
As an another example, from realization perspective even on the same
NRP, a slice requests leveraging on
[I-D.draft-ietf-teas-ietf-network-slice-nbi-yang] without topology
differentiation could imply the realization of all the connectivity
constructs on the same manner. For instance, implementing all of
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them within the same VRF in a L3VPN. The usage of the topological
views can help the provider to infer differentiated realization of
some of the connectivity constructs, for instance, by implementing
them on different VRFs. This can have operational advantages (e.g.,
adding new nodes / SDPs could affect / imply limit the necessary VRF
reconfiguration only to the one including affected connectivity
constructs).
Finally, by using customer intent topology it can be easier for the
slice provider to infer different technologies for sets of
connectivity constructs of every topology segment (e.g., IP/MPLS,
optical, microwave, etc).
1.2. Terminologies and Notations
The following terminologies for describing network slices are defined
in [RFC9543] and are not redefined herein.
* Network Slice (NS)
* Network Slice Customer
* Network Slice Service Provider
* Network Slice Controller (NSC)
* Network Resource Partition (NRP)
The following terms are defined and used in this document.
* Customer Intent Topology: A topology defined by the customer and
provided as input to the network slice service provider
(specifically, the Network Slice Controller or NSC). It
represents the customer's desired network topology.
* Abstract Topology: A topology exposed to the customer by the
network slice service provider prior to the creation of network
slices. The provider may optionally uses an abstract topology to
expose useful information, such as available resources to the
customer, which can facilitate the build-up of customer intent
topologies by the customer.
* NRP Topology: A topology internal to the NSC to facilitate the
mapping of network slices to underlying network resources.
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1.3. Tree Diagram
Tree diagrams used in this document follow the notation defined in
[RFC8340].
1.4. Prefixes in Data Node Names
In this document, names of data nodes and other data model objects
are prefixed using the standard prefix associated with the
corresponding YANG imported modules, as shown in Table 1.
+==========+============================+===========+
| Prefix | YANG Module | Reference |
+==========+============================+===========+
| yang | ietf-yang-types | [RFC6991] |
+----------+----------------------------+-----------+
| inet | ietf-inet-types | [RFC6991] |
+----------+----------------------------+-----------+
| nt | ietf-network-topology | [RFC8345] |
+----------+----------------------------+-----------+
| nw | ietf-network-topology | [RFC8345] |
+----------+----------------------------+-----------+
| tet | ietf-te-topology | [RFC8795] |
+----------+----------------------------+-----------+
| ns-path | ietf-ns-underlay-path | RFC XXXX |
+----------+----------------------------+-----------+
| ns-topo | ietf-ns-topo | RFC XXXX |
+----------+----------------------------+-----------+
| ietf-nss | ietf-network-slice-service | RFC YYYY |
+----------+----------------------------+-----------+
Table 1: Prefixes and Corresponding YANG Modules
RFC Editor Note: Please replace XXXX with the RFC number assigned to
this document. Please replace YYYY with the RFC number assigned to
[I-D.ietf-teas-ietf-network-slice-nbi-yang]. Please remove this
note.
2. Modeling Considerations
A network slice topology is a cusomer intent topology modeled as
network topology defined in [RFC8345], with augmentations. A new
network type "network-slice" is defined in this document.
When a network topology data instance contains the network-slice
network type, it represents an instance of a network slice topology.
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This data model augments the network topology model by incorporating
intent-based Service-Level Objectives (SLOs) and Service-Level
Expectations (SLEs). These apply to various components within the
customer intent topology, including nodes, links, and termination
points (TPs).
2.1. Relationship with Traffic Engineering (TE)-based Topology
The model defined in this document can be combined through multi-
inheritance with other topology data models, such as Traffic
Engineering (TE) topologies described in [RFC8795] or Optical
Transport Network (OTN) topologies described in
[I-D.ietf-ccamp-otn-topo-yang]. This flexibility allows the creation
of technology-specific customer intent topologies tailored to
specific network requirements.
2.2. Relationship with Service Attachment Point (SAP) Topology
[RFC9408] introduces a YANG data model that represents an abstract
view of the provider network topology. This model includes a list of
Service Attachment Points (SAPs), where customer services can be
connected. The SAP topology is made visible to customers by the
provider before configuring network slice services. In contrast, the
customer intent topology described in this document captures a
customer's intentions, while the provider acts as the recipient of
these intents. As a result, these two models serve distinct
purposes.
In certain scenarios, customers can leverage the SAP topology to
construct customer intent topologies to aid in the realization of
their intended network configurations. For instance, within a node
of a customer intent topology, the Link Termination Point (LTP)
identifiers may explicitly reference their supporting Termination
Points (TPs), which correspond to the SAPs exposed in the provider's
SAP model. However, the specifics of this mechanism fall beyond the
scope of this document.
2.3. Relationship with ACTN Virtual Network (VN)
[RFC8453] and [I-D.ietf-teas-actn-vn-yang] introduce the concept of a
Virtual Network (VN), which can be presented to customers. These VNs
are constructed from abstractions of the underlying networks,
specifically those that are traffic-engineering (TE) capable. While
VNs share similarities with RFC 9543 network slicing, they operate
under the assumption of TE-capable networks.
Two distinct types of VNs are defined:
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* Type 1 VN: Modeled as a single abstract node with edge-to-edge
connectivity between customer endpoints.
* Type 2 VN: Modeled as a single abstract node with an underlay
topology, allowing configuration of intended underlay paths for
connections within the single abstract node.
The topologies for VNs, including both the single-node abstract
topology and the underlay topology, can either be mutually agreed
upon between the Customer Network Controller (CNC) and the Multi-
Domain Service Coordinator (MDSC) prior to VN creation, or they can
be created as part of VN instantiation by the customer.
In the context of network slicing, [RFC9543] defines a network slice
service as a collection of connectivity constructs between pairs of
Service Demarcation Points (SDPs). This concept closely resembles
the Type 1 VN, which is implemented as a single abstract node.
[I-D.ietf-teas-ietf-network-slice-nbi-yang] further elaborates on
network slices by incorporating references to a customer intent
topology based on [RFC8345]. This approach aligns with the ACTN Type
2 VN, although without specifying the explicit use of such a
topology.
Consequently, the data model defined in this document serves as a
complementary option to the data model outlined in
[I-D.ietf-teas-ietf-network-slice-nbi-yang]. It empowers customers
to define a customized intent topology specifically tailored for
their network slices.
2.3.1. Consideration on Reusing ACTN VN for Network Slicing
The ACTN VN model provides a self-consistent method for expressing
connectivity intents (Type 1 VN) and optional path constraints (Type
2 VN) using TE metrics and TE objective functions defined in
[RFC8795]. Type 2 VN path constraints rely on Type 1 VN for
expressing connectivity intents.
On the other hand, RFC9543 network slice services provide
connectivity intents equivalent to Type 1 VN, using SLO and SLE
attributes in a technology-agnostic manner not tied to TE
technologies. This distinction is detailed in Appendix D of
[I-D.ietf-teas-ietf-network-slice-nbi-yang].
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Reusing the Type 2 VN for defining customer intent topologies
alongside the RFC9543 network slice service model would result in
duplicated information for connectivity intents (SDPs and
connectivity-constructs vs. LTPs and connectivity matrices), and
additionally, would bind the network slice solution to TE
technologies.
The proposed models in this draft aim to deliver a solution
equivalent to Type 2 VN within the context of network slicing. This
complements the existing solution outlined in
[I-D.ietf-teas-ietf-network-slice-nbi-yang], while ensuring
consistency.
2.4. Data Model Relationship
The data model presented in this document builds upon the generic
network topology model defined in [RFC8345]. Other data models,
including OTN Slicing (as defined in
[I-D.ietf-ccamp-yang-otn-slicing]), can leverage this extended model.
The relationship of the related data models is illustrated in
Figure 1. Within this diagram, the box outlined with dotted lines
specifically represents the data model defined in this document.
+----------+ +----------+
| Network | | Network |
| Slice | | Topology +
| NBI YANG +------+ | Model |
| Model | | | RFC 8345 |
+----+-----+ | +-----+----+
| | |
|augments |augments |augments
| | |
+----^-----+ | ......^.....
| OTN | +----------< Network :
| Slicing | augments : Slice :
| Model >-----------------: Topology :
| | : Model :
+----------+ :..........:
Figure 1: Model Relationship
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3. Model Applicability
Network slicing can be achieved through various technologies. The
data model defined in this document serves as a means for configuring
resource reservation-based network slices. In this approach,
resources for network slices are reserved and represented using a
customer intent topology. This topology can then be mapped to a
network resource partition (NRP) and realized based on the scenarios
outlined in [RFC9543].
Network slices can be abstracted in various ways, depending on the
specific requirements of the network slice customer. For instance, a
customer might request a network slice with direct connectivity
between pairs of Service Demarcation Points (SDPs). Within this
network slice, each connectivity construct could be further supported
by an end-to-end tunnel that follows a specific path defined in a
customer intent topology, which the customer provides. The resources
associated with each link are immediately commissioned during the
network slice configuration process.
Alternatively, a customer can request resources to be reserved for
potential network slices through a customer intent topology. These
reserved resources are not immediately commissioned at the time of
the request. Instead, they serve as a pool of allocated resources
that the customer can utilize to build network slices in the future.
By adopting this approach, customers gain the flexibility to share
resources across multiple endpoints and activate them on demand.
In the example shown in Figure 2, two topology intents named as
Network Slice Blue and Network Slice Red, are created by separate
customers and delivered to the network slice service provider. The
provider maps the two intents to corresponding network resource
partitions (NRPs) internally. In realizing the network resource
partitions, node virtualization is used to separate and allocate
resources in physical devices. Two virtual routers VR1 and VR2 are
created over physical router R1, and two virtual routers VR3 and VR4
are created over physical router R2, respectively. Each of the
virtual routers,as a partition of the physical router, takes a
portion of the resources such as ports and memory in the physical
router.
Depending on the requirements and the implementations, they may share
certain resources such as processors, ASICs, and switch fabric.
A network slice customer has the capability to configure customer
intent topologies without needing any prior knowledge of the
provider's network or resource availability. However, this approach
could potentially create challenges for the provider in understanding
and realizing the intended topology.
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Alternatively, the provider can choose to describe the available
resources and capabilities in the form of an abstract topology, which
is then exposed to the customer before network slice requests. By
doing so, the provider empowers the customer to build their
customized intent topologies based on this pre-exposed information.
This approach streamlines the process, minimizing unnecessary
negotiations between the customer and the provider. The process and
the data models for the provider to expose abstract topologies are
outside the scope of this document.
The provider communicates the operational state of the customer
intent topology, reflecting the allocated resources that result from
negotiations between the customer and the provider. Subsequently,
customers can process the requested customer intent topology and
seamlessly integrate it into their own network topology.
Importantly, this relationship between the customer and provider can
be recursive. For instance, a customer who requests network slices
can also serve as a provider, offering network slice services to its
own customers further up the hierarchy.
As an example, Appendix B. shows the JSON encoded data instances of
the customer topology intent for Network Slice Blue.
Customer Topology (Merged) Customer Topology (Merged)
Network Slice Blue Network Slice Red
+---+ +---+ +---+
-----|R3 |--- ---|R2 |------|R3 |
/ +---+ +---+ +---+
+---+ +---+ ^ ^ ^ \ +---+
---|R1 |------|R2 | | | | -----|R4 |---
+---+ +---+ | | | +---+
^ ^ v v v ^
| | +---+ +---+ +---+ |
| | -----|VR5|--- ---|VR2|------|VR4| |
v v / +---+ +---+ +---+ v
+---+ +---+ \ +---+
---|VR1|------|VR3| -----|VR6|---
+---+ +---+ +---+
Customer Topology (Intended) Customer Topology (Intended)
Network Slice Blue Network Slice Red
Customers
---------------------------------------------------------------------
Provider
Customized Topology (Network Resouce Partition)
Provider Network with Virtual Devices
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Network Slice Blue: VR1, VR3, VR5 +---+
----------|VR5|------
/ +---+
+---+ +---+
------|VR1|---------|VR3|
+---+ +---+
------|VR2|---------|VR4|
+---+ +---+
\ +---+
----------|VR6|------
Network Slice Red: VR2, VR4, VR6 +---+
Virtual Devices
---------------------------------------------------------------------
Physical Devices
Native Topology
Provider Network with Physical Devices
+---+
----------|R3 |------
/ +---+
+---+ +---+
======|R1 |=========|R2 |
+---+ +---+
\ +---+
----------|R4 |------
+---+
Figure 2: Network Slicing Topologies for Virtualization
4. YANG Model Overview
The YANG data model in this draft consists of two modules for
flexible use and augmentation: - The first YANG module defines a
customer intent topology, with SLO and SLE associated with the
topological constructs. - The second YANG module extends the YANG
model defined in [I-D.ietf-teas-ietf-network-slice-nbi-yang] by
adding underlay paths to the connectivity constructs.
Within the YANG model, the following constructs and attributes are
defined: - Network Topology: This represents a set of shared and
reserved resources, organized as a virtual topology connecting all
endpoints. Customers can utilize this network topology to define
detailed connectivity paths traversing the topology. Additionally,
it enables resource sharing between different endpoints.
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* Service-Level Objectives (SLOs): These objectives are associated
with various objects within the topology, including nodes, links,
and termination points. SLOs provide guidelines for achieving
specific performance or quality targets.
5. Model Tree Structure
5.1. Network Slice Topology Model Tree Structure
module: ietf-ns-topo
augment /nw:networks/nw:network/nw:network-types:
+--rw network-slice!
augment /nw:networks/nw:network:
+--rw (slo-sle-policy)?
+--:(standard)
| +--rw slo-sle-template? slice-template-ref
+--:(custom)
+--rw service-slo-sle-policy
+--rw description? string
+--rw slo-policy
| +--rw metric-bound* [metric-type]
| | +--rw metric-type identityref
| | +--rw metric-unit string
| | +--rw value-description? string
| | +--rw percentile-value? percentile
| | +--rw bound? uint64
| +--rw availability? identityref
| +--rw mtu? uint32
+--rw sle-policy
+--rw security* identityref
+--rw isolation* identityref
+--rw max-occupancy-level? uint8
+--rw path-constraints
+--rw service-functions
+--rw diversity
+--rw diversity-type?
te-types:te-path-disjointness
augment /nw:networks/nw:network/nw:node:
+--rw (slo-sle-policy)?
+--:(standard)
| +--rw slo-sle-template? slice-template-ref
+--:(custom)
+--rw service-slo-sle-policy
+--rw description? string
+--rw slo-policy
| +--rw metric-bound* [metric-type]
| | +--rw metric-type identityref
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| | +--rw metric-unit string
| | +--rw value-description? string
| | +--rw percentile-value? percentile
| | +--rw bound? uint64
| +--rw availability? identityref
| +--rw mtu? uint32
+--rw sle-policy
+--rw security* identityref
+--rw isolation* identityref
+--rw max-occupancy-level? uint8
+--rw path-constraints
+--rw service-functions
+--rw diversity
+--rw diversity-type?
te-types:te-path-disjointness
augment /nw:networks/nw:network/nw:node/nt:termination-point:
+--rw (slo-sle-policy)?
+--:(standard)
| +--rw slo-sle-template? slice-template-ref
+--:(custom)
+--rw service-slo-sle-policy
+--rw description? string
+--rw slo-policy
| +--rw metric-bound* [metric-type]
| | +--rw metric-type identityref
| | +--rw metric-unit string
| | +--rw value-description? string
| | +--rw percentile-value? percentile
| | +--rw bound? uint64
| +--rw availability? identityref
| +--rw mtu? uint32
+--rw sle-policy
+--rw security* identityref
+--rw isolation* identityref
+--rw max-occupancy-level? uint8
+--rw path-constraints
+--rw service-functions
+--rw diversity
+--rw diversity-type?
te-types:te-path-disjointness
augment /nw:networks/nw:network/nt:link:
+--rw (slo-sle-policy)?
+--:(standard)
| +--rw slo-sle-template? slice-template-ref
+--:(custom)
+--rw service-slo-sle-policy
+--rw description? string
+--rw slo-policy
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| +--rw metric-bound* [metric-type]
| | +--rw metric-type identityref
| | +--rw metric-unit string
| | +--rw value-description? string
| | +--rw percentile-value? percentile
| | +--rw bound? uint64
| +--rw availability? identityref
| +--rw mtu? uint32
+--rw sle-policy
+--rw security* identityref
+--rw isolation* identityref
+--rw max-occupancy-level? uint8
+--rw path-constraints
+--rw service-functions
+--rw diversity
+--rw diversity-type?
te-types:te-path-disjointness
Figure 3: Tree diagram for network slice topology
5.2. Network Slice Underlay Path Model Tree Structure
module: ietf-ns-underlay-path
augment /ietf-nss:network-slice-services/ietf-nss:slice-service
/ietf-nss:connection-groups/ietf-nss:connection-group
/ietf-nss:slo-sle-policy/ietf-nss:custom
/ietf-nss:service-slo-sle-policy/ietf-nss:sle-policy
/ietf-nss:path-constraints:
+--rw underlay-path
+--rw network-ref? -> /nw:networks/network/network-id
+--rw path-element* [index]
+--rw index uint32
+--rw is-strict-hop? boolean
+--rw (type)?
+--:(node-hop)
| +--rw node-id? nw:node-id
+--:(link-hop)
| +--rw link-id? nt:link-id
+--:(tp-hop)
+--rw tp-id? nt:tp-id
augment /ietf-nss:network-slice-services/ietf-nss:slice-service
/ietf-nss:connection-groups/ietf-nss:connection-group
/ietf-nss:connectivity-construct/ietf-nss:slo-sle-policy
/ietf-nss:custom/ietf-nss:service-slo-sle-policy
/ietf-nss:sle-policy/ietf-nss:path-constraints:
+--rw underlay-path
+--rw network-ref? -> /nw:networks/network/network-id
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+--rw path-element* [index]
+--rw index uint32
+--rw is-strict-hop? boolean
+--rw (type)?
+--:(node-hop)
| +--rw node-id? nw:node-id
+--:(link-hop)
| +--rw link-id? nt:link-id
+--:(tp-hop)
+--rw tp-id? nt:tp-id
augment /ietf-nss:network-slice-services/ietf-nss:slice-service
/ietf-nss:connection-groups/ietf-nss:connection-group
/ietf-nss:connectivity-construct/ietf-nss:type
/ietf-nss:a2a/ietf-nss:a2a-sdp/ietf-nss:slo-sle-policy
/ietf-nss:custom/ietf-nss:service-slo-sle-policy
/ietf-nss:sle-policy/ietf-nss:path-constraints:
+--rw underlay-path
+--rw network-ref? -> /nw:networks/network/network-id
+--rw path-element* [index]
+--rw index uint32
+--rw is-strict-hop? boolean
+--rw (type)?
+--:(node-hop)
| +--rw node-id? nw:node-id
+--:(link-hop)
| +--rw link-id? nt:link-id
+--:(tp-hop)
+--rw tp-id? nt:tp-id
Figure 4: Tree diagram for underlay path
6. YANG Modules
6.1. YANG Module for Network Slice Topology
<CODE BEGINS> file "ietf-ns-topo@2024-07-02.yang"
module ietf-ns-topo {
yang-version 1.1;
namespace
"urn:ietf:params:xml:ns:yang:ietf-ns-topo";
prefix "ns-topo";
import ietf-network {
prefix "nw";
reference
"RFC 8345: A YANG Data Model for Network Topologies";
}
import ietf-network-topology {
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prefix "nt";
reference
"RFC 8345: A YANG Data Model for Network Topologies";
}
import ietf-network-slice-service {
prefix "ietf-nss";
reference
"draft-ietf-teas-ietf-network-slice-nbi-yang-10:
IETF Network Slice Service YANG Model";
}
organization
"IETF TEAS Working Group";
contact
"WG Web: <http://tools.ietf.org/wg/teas/>
WG List: <mailto:teas@ietf.org>
Editor: Xufeng Liu
<mailto:xufeng.liu.ietf@gmail.com>
Editor: Italo Busi
<mailto:italo.busi@huawei.com>
Editor: Aihua Guo
<mailto:aihuaguo.ietf@gmail.com>
Editor: Sergio Belotti
<mailto:sergio.belotti@nokia.com>
Editor: Luis M. Contreras
<mailto:luismiguel.contrerasmurillo@telefonica.com>";
description
"This module defines a base YANG data model for configuring
customer intent topologies for RFC9543 network slices.
The model fully conforms to the Network Management Datastore
Architecture (NMDA).
Copyright (c) 2023 IETF Trust and the persons
identified as authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with
or without modification, is permitted pursuant to, and
subject to the license terms contained in, the Revised
BSD License set forth in Section 4.c of the IETF Trust's
Legal Provisions Relating to IETF Documents
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(https://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX; see
the RFC itself for full legal notices.";
revision 2024-07-02 {
description "Initial revision";
reference
"RFC XXXX: IETF Network Slice Topology YANG Data Model";
}
/*
* Augmented data nodes
*/
/* network type augments */
augment "/nw:networks/nw:network/nw:network-types" {
description
"Defines the Network Slice topology type.";
container network-slice {
presence "Indicates a Network Slice topology";
description
"Its presence identifies the Network Slice type.";
}
}
/* network topology augments */
augment "/nw:networks/nw:network" {
when "./nw:network-types/ns-topo:network-slice" {
description
"Augmentation parameters apply only for networks
of type Network Slice topology.";
}
description
"SLO and SLE for topology.";
uses ietf-nss:service-slo-sle-policy;
}
/* network node augments */
augment "/nw:networks/nw:network/nw:node" {
when "../nw:network-types/ns-topo:network-slice" {
description
"Augmentation parameters apply only for networks
of type Network Slice topology.";
}
description
"SLO and SLE for nodes.";
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uses ietf-nss:service-slo-sle-policy;
}
/* network node's termination point augments */
augment "/nw:networks/nw:network/nw:node" +
"/nt:termination-point" {
when "../../nw:network-types/ns-topo:network-slice" {
description
"Augmentation parameters apply only for networks
of type Network Slice topology.";
}
description
"SLO and SLE for termination points.";
uses ietf-nss:service-slo-sle-policy;
}
/* network link augments */
augment "/nw:networks/nw:network/nt:link" {
when "../nw:network-types/ns-topo:network-slice" {
description
"Augmentation parameters apply only for networks
of type Network Slice topology.";
}
description
"SLO and SLE for links.";
uses ietf-nss:service-slo-sle-policy;
}
}
<CODE ENDS>
Figure 5: YANG model for network slice topology
6.2. YANG Module for Network Slice Underlay Path
<CODE BEGINS> file "ietf-ns-underlay-path@2024-07-02.yang"
module ietf-ns-underlay-path {
yang-version 1.1;
namespace
"urn:ietf:params:xml:ns:yang:ietf-ns-underlay-path";
prefix "ns-path";
import ietf-network {
prefix "nw";
reference
"RFC 8345: A YANG Data Model for Network Topologies";
}
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import ietf-network-topology {
prefix "nt";
reference
"RFC 8345: A YANG Data Model for Network Topologies";
}
import ietf-network-slice-service {
prefix "ietf-nss";
reference
"draft-ietf-teas-ietf-network-slice-nbi-yang-05:
IETF Network Slice Service YANG Model";
}
organization
"IETF TEAS Working Group";
contact
"WG Web: <http://tools.ietf.org/wg/teas/>
WG List: <mailto:teas@ietf.org>
Editor: Xufeng Liu
<mailto:xufeng.liu.ietf@gmail.com>
Editor: Italo Busi
<mailto:italo.busi@huawei.com>
Editor: Aihua Guo
<mailto:aihuaguo.ietf@gmail.com>
Editor: Sergio Belotti
<mailto:sergio.belotti@nokia.com>
Editor: Luis M. Contreras
<mailto:luismiguel.contrerasmurillo@telefonica.com>";
description
"This module defines a base YANG data model for configuring
the underlay path of connectivity intent over a customer
intent topology for RFC9543 network slices.
The model fully conforms to the Network Management Datastore
Architecture (NMDA).
Copyright (c) 2023 IETF Trust and the persons
identified as authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with
or without modification, is permitted pursuant to, and
subject to the license terms contained in, the Revised
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BSD License set forth in Section 4.c of the IETF Trust's
Legal Provisions Relating to IETF Documents
(https://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX; see
the RFC itself for full legal notices.";
revision 2024-07-02 {
description "Initial revision";
reference
"RFC XXXX: IETF Network Slice Topology YANG Data Model";
}
/*
* Groupings
*/
grouping underlay-path {
description
"Underlay explicit path within a customer intent
topology.";
container underlay-path {
description
"Defines an underlay explicit path within specific
customer intent topology.";
uses nw:network-ref;
list path-element {
key "index";
description
"List of path elements.";
leaf index {
type uint32;
description
"Index of the hop within the underlay path.";
}
leaf is-strict-hop {
type boolean;
description
"Indicate whether the hop is strict or loose";
}
choice type {
description
"Type of the hop.";
case node-hop {
leaf node-id {
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type nw:node-id;
description
"Node identifier.";
}
}
case link-hop {
leaf link-id {
type nt:link-id;
description
"Link identifier.";
}
}
case tp-hop {
leaf tp-id {
type nt:tp-id;
description
"Termination Point (TP) identifier.";
}
}
}
}
}
}
/*
* Augmented data nodes
*/
augment "/ietf-nss:network-slice-services" +
"/ietf-nss:slice-service" +
"/ietf-nss:connection-groups" +
"/ietf-nss:connection-group" +
"/ietf-nss:slo-sle-policy" +
"/ietf-nss:custom" +
"/ietf-nss:service-slo-sle-policy" +
"/ietf-nss:sle-policy" +
"/ietf-nss:path-constraints" {
description
"Underlay path for connection group.";
uses underlay-path;
}
augment "/ietf-nss:network-slice-services" +
"/ietf-nss:slice-service" +
"/ietf-nss:connection-groups" +
"/ietf-nss:connection-group" +
"/ietf-nss:connectivity-construct" +
"/ietf-nss:slo-sle-policy" +
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"/ietf-nss:custom" +
"/ietf-nss:service-slo-sle-policy" +
"/ietf-nss:sle-policy" +
"/ietf-nss:path-constraints" {
description
"Underlay path for connectivity construct.";
uses underlay-path;
}
augment "/ietf-nss:network-slice-services" +
"/ietf-nss:slice-service" +
"/ietf-nss:connection-groups" +
"/ietf-nss:connection-group" +
"/ietf-nss:connectivity-construct" +
"/ietf-nss:type" +
"/ietf-nss:a2a" +
"/ietf-nss:a2a-sdp" +
"/ietf-nss:slo-sle-policy" +
"/ietf-nss:custom" +
"/ietf-nss:service-slo-sle-policy" +
"/ietf-nss:sle-policy" +
"/ietf-nss:path-constraints" {
description
"Underlay path for a2a connectivity constructs.";
uses underlay-path;
}
}
<CODE ENDS>
Figure 6: YANG model for underlay path
7. Manageability Considerations
To ensure the security and controllability of physical resource
isolation, slice-based independent operation and management are
required to achieve management isolation. Each network slice
typically requires dedicated accounts, permissions, and resources for
independent access and O&M. This mechanism is to guarantee the
information isolation among slice tenants and to avoid resource
conflicts. The access to slice management functions will only be
permitted after successful security checks.
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8. Security Considerations
The YANG module specified in this document defines a schema for data
that is designed to be accessed via network management protocols such
as NETCONF [RFC6241] or RESTCONF [RFC8040]. The lowest NETCONF layer
is the secure transport layer, and the mandatory-to-implement secure
transport is Secure Shell (SSH) [RFC6242]. The lowest RESTCONF layer
is HTTPS, and the mandatory-to-implement secure transport is TLS
[RFC8446].
The NETCONF access control model [RFC8341] provides the means to
restrict access for particular NETCONF or RESTCONF users to a
preconfigured subset of all available NETCONF or RESTCONF protocol
operations and content.
There are a number of data nodes defined in this YANG module that are
writable/creatable/deletable (i.e., config true, which is the
default). These data nodes may be considered sensitive or vulnerable
in some network environments. Write operations (e.g., edit-config)
to these data nodes without proper protection can have a negative
effect on network operations. Considerations in Section 8 of
[RFC8795] are also applicable to their subtrees in the module defined
in this document.
Some of the readable data nodes in this YANG module may be considered
sensitive or vulnerable in some network environments. It is thus
important to control read access (e.g., via get, get-config, or
notification) to these data nodes. Considerations in Section 8 of
[RFC8795] are also applicable to their subtrees in the module defined
in this document.
9. IANA Considerations
It is proposed to IANA to assign new URIs from the "IETF XML
Registry" [RFC3688] as follows:
URI: urn:ietf:params:xml:ns:yang:ietf-ns-topo
Registrant Contact: The IESG
XML: N/A; the requested URI is an XML namespace.
URI: urn:ietf:params:xml:ns:yang:ietf-ns-underlay-path
Registrant Contact: The IESG
XML: N/A; the requested URI is an XML namespace.
This document registers two YANG modules in the YANG Module Names
registry [RFC6020].
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name: ietf-ns-topo
namespace: urn:ietf:params:xml:ns:yang:ietf-ns-topo
prefix: ns-topo
reference: RFC XXXX
name: ietf-ns-underlay-path
namespace: urn:ietf:params:xml:ns:yang:ietf-ns-underlay-path
prefix: ns-path
reference: RFC XXXX
10. References
10.1. Normative References
[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
DOI 10.17487/RFC3688, January 2004,
<https://www.rfc-editor.org/info/rfc3688>.
[RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for
the Network Configuration Protocol (NETCONF)", RFC 6020,
DOI 10.17487/RFC6020, October 2010,
<https://www.rfc-editor.org/info/rfc6020>.
[RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,
and A. Bierman, Ed., "Network Configuration Protocol
(NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011,
<https://www.rfc-editor.org/info/rfc6241>.
[RFC6242] Wasserman, M., "Using the NETCONF Protocol over Secure
Shell (SSH)", RFC 6242, DOI 10.17487/RFC6242, June 2011,
<https://www.rfc-editor.org/info/rfc6242>.
[RFC6991] Schoenwaelder, J., Ed., "Common YANG Data Types",
RFC 6991, DOI 10.17487/RFC6991, July 2013,
<https://www.rfc-editor.org/info/rfc6991>.
[RFC7950] Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
RFC 7950, DOI 10.17487/RFC7950, August 2016,
<https://www.rfc-editor.org/info/rfc7950>.
[RFC7951] Lhotka, L., "JSON Encoding of Data Modeled with YANG",
RFC 7951, DOI 10.17487/RFC7951, August 2016,
<https://www.rfc-editor.org/info/rfc7951>.
[RFC8040] Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017,
<https://www.rfc-editor.org/info/rfc8040>.
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[RFC8340] Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams",
BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018,
<https://www.rfc-editor.org/info/rfc8340>.
[RFC8341] Bierman, A. and M. Bjorklund, "Network Configuration
Access Control Model", STD 91, RFC 8341,
DOI 10.17487/RFC8341, March 2018,
<https://www.rfc-editor.org/info/rfc8341>.
[RFC8342] Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K.,
and R. Wilton, "Network Management Datastore Architecture
(NMDA)", RFC 8342, DOI 10.17487/RFC8342, March 2018,
<https://www.rfc-editor.org/info/rfc8342>.
[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>.
[RFC8446] Rescorla, E., "The Transport Layer Security (TLS) Protocol
Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018,
<https://www.rfc-editor.org/info/rfc8446>.
[RFC8453] Ceccarelli, D., Ed. and Y. Lee, Ed., "Framework for
Abstraction and Control of TE Networks (ACTN)", RFC 8453,
DOI 10.17487/RFC8453, August 2018,
<https://www.rfc-editor.org/info/rfc8453>.
[RFC8795] Liu, X., Bryskin, I., Beeram, V., Saad, T., Shah, H., and
O. Gonzalez de Dios, "YANG Data Model for Traffic
Engineering (TE) Topologies", RFC 8795,
DOI 10.17487/RFC8795, August 2020,
<https://www.rfc-editor.org/info/rfc8795>.
[RFC9408] Boucadair, M., Ed., Gonzalez de Dios, O., Barguil, S., Wu,
Q., and V. Lopez, "A YANG Network Data Model for Service
Attachment Points (SAPs)", RFC 9408, DOI 10.17487/RFC9408,
June 2023, <https://www.rfc-editor.org/info/rfc9408>.
[RFC9543] Farrel, A., Ed., Drake, J., Ed., Rokui, R., Homma, S.,
Makhijani, K., Contreras, L., and J. Tantsura, "A
Framework for Network Slices in Networks Built from IETF
Technologies", RFC 9543, DOI 10.17487/RFC9543, March 2024,
<https://www.rfc-editor.org/info/rfc9543>.
10.2. Informative References
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[I-D.contreras-teas-slice-controller-models]
Contreras, L. M., Rokui, R., Tantsura, J., Wu, B., Liu,
X., Dhody, D., and S. Belotti, "IETF Network Slice
Controller and its associated data models", Work in
Progress, Internet-Draft, draft-contreras-teas-slice-
controller-models-05, 13 March 2023,
<https://datatracker.ietf.org/doc/html/draft-contreras-
teas-slice-controller-models-05>.
[I-D.draft-ietf-teas-ietf-network-slice-nbi-yang]
Wu, B., Dhody, D., Rokui, R., Saad, T., and J. Mullooly,
"A YANG Data Model for the RFC 9543 Network Slice
Service", Work in Progress, Internet-Draft, draft-ietf-
teas-ietf-network-slice-nbi-yang-13, 9 May 2024,
<https://datatracker.ietf.org/doc/html/draft-ietf-teas-
ietf-network-slice-nbi-yang-13>.
[I-D.ietf-ccamp-otn-topo-yang]
Zheng, H., Busi, I., Liu, X., Belotti, S., and O. G. de
Dios, "A YANG Data Model for Optical Transport Network
Topology", Work in Progress, Internet-Draft, draft-ietf-
ccamp-otn-topo-yang-19, 25 June 2024,
<https://datatracker.ietf.org/doc/html/draft-ietf-ccamp-
otn-topo-yang-19>.
[I-D.ietf-ccamp-yang-otn-slicing]
Guo, A., Contreras, L. M., Belotti, S., Rokui, R., Xu, Y.,
Zhao, Y., and X. Liu, "Framework and Data Model for OTN
Network Slicing", Work in Progress, Internet-Draft, draft-
ietf-ccamp-yang-otn-slicing-06, 24 January 2024,
<https://datatracker.ietf.org/doc/html/draft-ietf-ccamp-
yang-otn-slicing-06>.
[I-D.ietf-teas-actn-vn-yang]
Lee, Y., Dhody, D., Ceccarelli, D., Bryskin, I., and B. Y.
Yoon, "A YANG Data Model for Virtual Network (VN)
Operations", Work in Progress, Internet-Draft, draft-ietf-
teas-actn-vn-yang-29, 22 June 2024,
<https://datatracker.ietf.org/doc/html/draft-ietf-teas-
actn-vn-yang-29>.
[I-D.ietf-teas-ietf-network-slice-nbi-yang]
Wu, B., Dhody, D., Rokui, R., Saad, T., and J. Mullooly,
"A YANG Data Model for the RFC 9543 Network Slice
Service", Work in Progress, Internet-Draft, draft-ietf-
teas-ietf-network-slice-nbi-yang-13, 9 May 2024,
<https://datatracker.ietf.org/doc/html/draft-ietf-teas-
ietf-network-slice-nbi-yang-13>.
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Appendix A. Acknowledgments
The authors would like to thank Danielle Ceccarelli, Bo Wu, Mohamed
Boucadair, and Vishnu Beeram for providing valuable insights.
Appendix B. Data Tree for the Example in Section 3
B.1. Native Topology
This section contains an example of an instance data tree in the JSON
encoding [RFC7951]. The example instantiates "ietf-network" for the
topology of Network Slice Blue depicted in Figure 2.
=============== NOTE: '\' line wrapping per RFC 8792 ================
{
"ietf-network:networks": {
"network": [
{
"network-id": "example-customized-blue-topology",
"network-types": {
"ietf-ns-topo:network-slice": {
}
},
"node": [
{
"node-id": "VR1",
"ietf-ns-topo:service-slo-sle-policy": {
"sle-policy": {
"isolation": [
{
"ietf-network-slice-service:service-traffic-iso\
lation"
}
]
}
},
"ietf-network-topology:termination-point": [
{
"tp-id": "1-0-1"
},
{
"tp-id": "1-3-1"
}
]
},
{
"node-id": "VR3",
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"ietf-ns-topo:service-slo-sle-policy": {
"sle-policy": {
"isolation": [
{
"ietf-network-slice-service:service-traffic-iso\
lation"
}
]
}
},
"ietf-network-topology:termination-point": [
{
"tp-id": "3-1-1"
},
{
"tp-id": "3-5-1"
}
]
},
{
"node-id": "VR5",
"ietf-ns-topo:service-slo-sle-policy": {
"sle-policy": {
"isolation": [
{
"ietf-network-slice-service:service-traffic-iso\
lation"
}
]
}
},
"ietf-network-topology:termination-point": [
{
"tp-id": "5-3-1"
},
{
"tp-id": "5-0-1"
}
]
}
],
"ietf-network-topology:link": [
{
"link-id": "VR1,1-0-1,,",
"source": {
"source-node": "VR1",
"source-tp": "1-0-1"
},
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"ietf-ns-topo:service-slo-sle-policy": {
"slo-policy": {
"metric-bounds": {
"metric-bound": [
{
"metric-type": "ietf-network-slice-service:se\
rvice-slo-two-way-delay",
"metric-unit": "ms",
"bound": 60
}
]
}
},
"sle-policy": {
"isolation": [
{
"ietf-network-slice-service:service-traffic-iso\
lation"
}
]
}
}
},
{
"link-id": ",,VR1,1-0-1",
"destination": {
"dest-node": "VR1",
"dest-tp": "1-0-1"
},
"ietf-ns-topo:service-slo-sle-policy": {
"slo-policy": {
"metric-bounds": {
"metric-bound": [
{
"metric-type": "ietf-network-slice-service:se\
rvice-slo-two-way-delay",
"metric-unit": "ms",
"bound": 30
}
]
}
},
"sle-policy": {
"isolation": [
{
"ietf-network-slice-service:service-traffic-iso\
lation"
}
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]
}
}
},
{
"link-id": "VR1,1-3-1,VR3,3-1-1",
"source": {
"source-node": "VR1",
"source-tp": "1-3-1"
},
"destination": {
"dest-node": "VR3",
"dest-tp": "3-1-1"
},
"ietf-ns-topo:service-slo-sle-policy": {
"slo-policy": {
"metric-bounds": {
"metric-bound": [
{
"metric-type": "ietf-network-slice-service:se\
rvice-slo-two-way-delay",
"metric-unit": "ms",
"bound": 30
}
]
}
},
"sle-policy": {
"isolation": [
{
"ietf-network-slice-service:service-traffic-iso\
lation"
}
]
}
}
},
{
"link-id": "VR3,3-1-1,VR1,1-3-1",
"source": {
"source-node": "VR3",
"source-tp": "3-1-1"
},
"destination": {
"dest-node": "R1",
"dest-tp": "1-3-1"
},
"ietf-ns-topo:service-slo-sle-policy": {
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"slo-policy": {
"metric-bounds": {
"metric-bound": [
{
"metric-type": "ietf-network-slice-service:se\
rvice-slo-two-way-delay",
"metric-unit": "ms",
"bound": 30
}
]
}
},
"sle-policy": {
"isolation": [
{
"ietf-network-slice-service:service-traffic-iso\
lation"
}
]
}
}
},
{
"link-id": "VR3,3-5-1,VR5,5-3-1",
"source": {
"source-node": "VR3",
"source-tp": "3-5-1"
},
"destination": {
"dest-node": "VR5",
"dest-tp": "5-3-1"
},
"ietf-ns-topo:service-slo-sle-policy": {
"slo-policy": {
"metric-bounds": {
"metric-bound": [
{
"metric-type": "ietf-network-slice-service:se\
rvice-slo-two-way-delay",
"metric-unit": "ms",
"bound": 35
}
]
}
},
"sle-policy": {
"isolation": [
{
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"ietf-network-slice-service:service-traffic-iso\
lation"
}
]
}
}
},
{
"link-id": "VR5,5-3-1,VR3,3-5-1",
"source": {
"source-node": "VR5",
"source-tp": "5-3-1"
},
"destination": {
"dest-node": "VR3",
"dest-tp": "3-5-1"
},
"ietf-ns-topo:service-slo-sle-policy": {
"slo-policy": {
"metric-bounds": {
"metric-bound": [
{
"metric-type": "ietf-network-slice-service:se\
rvice-slo-two-way-delay",
"metric-unit": "ms",
"bound": 35
}
]
}
},
"sle-policy": {
"isolation": [
{
"ietf-network-slice-service:service-traffic-iso\
lation"
}
]
}
}
},
{
"link-id": "VR5,5-0-1,,",
"source": {
"source-node": "VR5",
"source-tp": "5-0-1"
},
"ietf-ns-topo:service-slo-sle-policy": {
"slo-policy": {
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"metric-bounds": {
"metric-bound": [
{
"metric-type": "ietf-network-slice-service:se\
rvice-slo-two-way-delay",
"metric-unit": "ms",
"bound": 25
}
]
}
},
"sle-policy": {
"isolation": [
{
"ietf-network-slice-service:service-traffic-iso\
lation"
}
]
}
}
},
{
"link-id": ",,VR5,5-0-1",
"destination": {
"dest-node": "VR5",
"dest-tp": "5-0-1"
},
"ietf-ns-topo:service-slo-sle-policy": {
"slo-policy": {
"metric-bounds": {
"metric-bound": [
{
"metric-type": "ietf-network-slice-service:se\
rvice-slo-two-way-delay",
"metric-unit": "ms",
"bound": 25
}
]
}
},
"sle-policy": {
"isolation": [
{
"ietf-network-slice-service:service-traffic-iso\
lation"
}
]
}
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}
}
],
"ietf-ns-topo:service-slo-sle-policy": {
"sle-policy": {
"isolation": [
{
"ietf-network-slice-service:service-traffic-isolati\
on"
}
]
}
}
}
]
}
}
Authors' Addresses
Xufeng Liu
Alef Edge
Email: xufeng.liu.ietf@gmail.com
Jeff Tantsura
Microsoft
Email: jefftant.ietf@gmail.com
Igor Bryskin
Individual
Email: i_bryskin@yahoo.com
Luis M. Contreras
Telefonica
Email: luismiguel.contrerasmurillo@telefonica.com
Qin Wu
Huawei
Email: bill.wu@huawei.com
Sergio Belotti
Nokia
Email: Sergio.belotti@nokia.com
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Reza Rokui
Ciena
Email: rrokui@ciena.com
Aihua Guo
Futurewei
Email: aihuaguo.ietf@gmail.com
Italo Busi
Huawei
Email: italo.busi@huawei.com
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