]> Huawei Technologies

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Huawei Technologies

101 Software Avenue, Yuhua District Nanjing 210012 CN lana.wubo@huawei.com

Routing TEAS Working Group This document provides a YANG data model to map IETF network slice service to Traffic Engineering (TE) models (e.g., the Virtual Network (VN) model or the TE Tunnel etc). It also supports mapping to the VPN Network models and Network Resource Partition (NRP) models. These models are referred to as IETF network slice service mapping model and are applicable generically for the seamless control and management of the IETF network slice service with underlying TE/VPN support. The models are principally used for monitoring and diagnostics of the management systems to show how the IETF network slice service requests are mapped onto underlying network resource and TE/VPN models.

Introduction Data models are a representation of objects that can be configured or monitored within a system. Within the IETF, YANG is the language of choice for documenting data models, and YANG models have been produced to allow configuration or modeling of a variety of network devices, protocol instances, and network services. The YANG model discussed in this document augments the IETF Network Slice Service YANG model , which is used to operate IETF Network Slices during the IETF Network Slice instantiation. This provides a way to map IETF network slice service to Traffic Engineering (TE) models (e.g., the Virtual Network (VN) model or the TE Tunnel etc). Alternatively, it also supports mapping to the VPN Network models and Network Resource Partition (NRP) models. The model supports:

• A mapping of the IETF Network Slice with the Network Resource Partition (NRP). As per , NRP is a collection of resources (bufferage, queuing, scheduling, etc.) in the underlay network. The NRP YANG model is specified in . The IETF Network Slice can be mapped to the NRP directly.
• A mapping of the IETF Network Slice with the VPN network models - LxNM. This mapping can be populated at the time of IETF network service realization. This mapping information is internal and used for monitoring and diagnostics purpose such as telemetry, auto-scaling, closed-loop automation. Note that the LxNM may further map to other TE resources as specified in . Optionally, a mapping to the NRP can also be populated.
• A mapping of the IETF Network Slice with the underlying TE resources directly. The TE resources could be in a form of VN, set of TE tunnels, TE abstract topology etc. This mapping can be populated by the network at the time of realization of the IETF network slice service. It is also possible to configure the mapping provided one is aware of NRP/VN/tunnels. This mapping mode is used only when the there is an awareness of VN or TE by the consumer of the model. Otherwise this mapping information is internal and used for monitoring and diagnostics purpose such as telemetry, auto-scaling, closed-loop automation.
• Possibility to request creation of a new VN/Tunnel to be binded to IETF network slice.
• Indication to share the VN/Tunnel sharing (with or without modification) for the IETF network slice.
• Support for configuration of underlying TE properties (as opposed to existing VN or tunnels).

Note: The RFC Editor will replace XXXX with the number assigned to the RFC once this draft becomes an RFC.

Conventions The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 when, and only when, they appear in all capitals, as shown here.

Tree Diagrams A simplified graphical representation of the data model is used in this document. The meaning of the symbols in these diagrams is defined in .

Prefixes in Data Node Names In this document, names of data nodes and other data model objects are often used without a prefix, as long as it is clear from the context in which YANG module each name is defined. Otherwise, names are prefixed using the standard prefix associated with the corresponding YANG module, as shown in Table 1.

Prefix	YANG module	Reference
nw	ietf-network
tsmt	ietf-te-service-mapping-types
l3vpn-ntw	ietf-l3vpn-ntw
l2vpn-ntw	ietf-l2vpn-ntw
ietf-ns	ietf-network-slice
nrp	ietf-nrp

References in the Model Following additional documents are referenced in the model defined in this document -

Document	Reference
Framework for IETF Network Slices

Model Design The YANG model specified in this document augments the IETF network slice service YANG model . Currently following mapping are supported:

• L3NM: The L3 network model (L3NM) describes a L3VPN Service in the Service Provider Network. It contains information of the Service Provider network and might include allocated resources. It can be used by network controllers to manage and control the L3VPN Service configuration in the Service Provider network. This model maps an IETF network slice to a L3VPN ID.
• L2NM: The L2 network model (L2NM) describes a L2VPN Service in the Service Provider Network. It contains information of the Service Provider network and might include allocated resources. It can be used by network controllers to manage and control the L2VPN Service configuration in the Service Provider network. This model maps an IETF network slice to a L2VPN ID.
• TE: The TE mapping is specified in . The mapping can be done to the following TE resouces:
  • Virtual Networks (VN)
  • TE-Tunnels
  • TE-Topology
• NRP: defines IETF network slice services that provide connectivity coupled with network resources commitment between a number of endpoints over a shared network infrastructure and, for scalability concerns, defines NRP to host one or a group of network slice services according to characteristics including SLOs and SLEs. Along with mapping to VPN, this model maps an IETF network slice to a NRP ID.

Open Questions The following open questions needs to be addressed in a future revision:

• Is there a need/use-case to map IETF Network slice Connection Group and/or Connectivity Construct as well?
• Is there a need/use-case to map IETF Network slice Endpoints?
• Is there a need to indicate "map-type" (new, share) for NRP and VPNs?

Tree Structure /nw:networks/network/nrp:nrp/nrp-id +--:(l3vpn) | +--rw l3vpn-id? leafref | +--rw l3vpn-nrp-id? | -> /nw:networks/network/nrp:nrp/nrp-id +--:(l2vpn) | +--rw l2vpn-id? leafref | +--rw l2vpn-nrp-id? | -> /nw:networks/network/nrp:nrp/nrp-id +--:(te) +--rw type? identityref +--rw te-policy | +--rw path-affinities-values | | +--rw path-affinities-value* [usage] | | ... | +--rw path-affinity-names | | +--rw path-affinity-name* [usage] | | ... | +--rw protection-type? identityref | +--rw availability-type? identityref +--rw (te)? | +--:(vn) | | +--rw vn* | | -> /vn:virtual-network/vn/vn-id | +--:(te-topo) | | +--rw te-topology-identifier | | | ... | | +--rw abstract-node? | | -> /nw:networks/network/node/node-id | +--:(te-tunnel) | +--rw te-tunnel* te:tunnel-ref | +--rw sr-policy* | [headend color-ref endpoint-ref] | {sr-policy}? | ... +--rw template-ref? leafref {template}? ]]>

YANG Model file "ietf-network-slice-mapping@2022-07-11.yang" module ietf-network-slice-mapping { yang-version 1.1; namespace "urn:ietf:params:xml:ns:yang:ietf-network-slice-mapping"; prefix ietf-nsm; import ietf-network { prefix nw; reference "RFC 8345: A YANG Data Model for Network Topologies"; } import ietf-network-slice { prefix ietf-ns; reference "I-D.ietf-teas-ietf-network-slice-nbi-yang: IETF Network Slice Service YANG Model"; } import ietf-te-service-mapping-types { prefix tsmt; reference "I-D.ietf-teas-te-service-mapping-yang: Traffic Engineering (TE) and Service Mapping YANG Data Model"; } import ietf-l3vpn-ntw { prefix l3vpn-ntw; reference "RFC9182: A YANG Network Data Model for Layer 3 VPNs"; } import ietf-l2vpn-ntw { prefix l2vpn-ntw; reference "I-D.ietf-opsawg-l2nm: A Layer 2 VPN Network YANG Model"; } import ietf-nrp { prefix nrp; reference "I-D.wd-teas-nrp-yang: A YANG Data Model for Network Resource Partition (NRP)"; } organization "IETF Traffic Engineering Architecture and Signaling (TEAS) Working Group"; contact "WG Web: WG List: Editor: Dhruv Dhody Bo Wu "; description "This module contains a YANG module to map the IETF Network Slice with Traffic Engineering (TE) or VPN Network models. Copyright (c) 2022 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 (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 2022-07-11 { description "initial version."; reference "RFC XXXX: IETF Network Slice Service Mapping YANG Model"; } identity map-to { description "Base identity from which specific map-to are derived."; } identity map-to-nrp { base map-to; description "Map to Network Resource Partition (NRP)"; } identity map-to-vpn { base map-to; description "Map to VPN"; } identity map-to-l3vpn { base map-to-vpn; description "Map to L3VPN"; } identity map-to-l2vpn { base map-to-vpn; description "Map to L2VPN"; } identity map-to-l1vpn { base map-to-vpn; description "Map to L1VPN"; } identity map-to-te { base map-to; description "Map to TE directly"; } grouping ns-mapping { description "Mapping between IETF network slice and Network Resource Partition (NRP)/VPN/TE"; container ns-mapping { description "The container for the mapping"; leaf map-to { type identityref { base map-to; } description "Mapping to NRP/VPN/TE"; } choice map { description "Mapping to NRP/VPN/TE"; case nrp { leaf nrp-id { type leafref { path "/nw:networks/nw:network" + "/nrp:nrp/nrp:nrp-id"; } description "A reference to NRP ID"; reference "I-D.ietf-teas-ietf-network-slices: Framework for IETF Network Slices"; } } case l3vpn { leaf l3vpn-id { type leafref { path "/l3vpn-ntw:l3vpn-ntw" + "/l3vpn-ntw:vpn-services" + "/l3vpn-ntw:vpn-service" + "/l3vpn-ntw:vpn-id"; } description "A reference to VPN ID"; } leaf l3vpn-nrp-id { type leafref { path "/nw:networks/nw:network" + "/nrp:nrp/nrp:nrp-id"; } description "An optional reference to NRP ID"; reference "I-D.ietf-teas-ietf-network-slices: Framework for IETF Network Slices"; } description "Mapping to L3NM"; reference "RFC9182: A YANG Network Data Model for Layer 3 VPNs"; } case l2vpn { leaf l2vpn-id { type leafref { path "/l2vpn-ntw:l2vpn-ntw" + "/l2vpn-ntw:vpn-services" + "/l2vpn-ntw:vpn-service" + "/l2vpn-ntw:vpn-id"; } description "A reference to VPN ID"; } leaf l2vpn-nrp-id { type leafref { path "/nw:networks/nw:network" + "/nrp:nrp/nrp:nrp-id"; } description "An optional reference to NRP ID"; reference "I-D.ietf-teas-ietf-network-slices: Framework for IETF Network Slices"; } description "Mapping to L2NM"; reference "I-D.ietf-opsawg-l2nm: A Layer 2 VPN Network YANG Model"; } case te { uses tsmt:te-mapping; description "Mapping to TE directly"; reference "I-D.ietf-teas-te-service-mapping-yang: Traffic Engineering (TE) and Service Mapping YANG Model"; } } } } augment "/ietf-ns:network-slices/ietf-ns:network-slice" { description "IETF Network Slice augmented to include the mapping information to the network slice realization"; container mapping { presence "Indicates Mapping information"; description "Container to augment IETF network slice to include NRP / VPN / TE mappings"; uses ns-mapping; } } } ]]>

Security Considerations TBD

IANA Considerations IANA is requested to make the following allocation for the URIs in the "ns" subregistry within the "IETF XML Registry" : IANA is requested to make the following allocation for the YANG module in the "YANG Module Names" registry :

References Normative References In many standards track documents several words are used to signify the requirements in the specification. These words are often capitalized. This document defines these words as they should be interpreted in IETF documents. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements. This document describes an IANA maintained registry for IETF standards which use Extensible Markup Language (XML) related items such as Namespaces, Document Type Declarations (DTDs), Schemas, and Resource Description Framework (RDF) Schemas. YANG is a data modeling language used to model configuration and state data manipulated by the Network Configuration Protocol (NETCONF), NETCONF remote procedure calls, and NETCONF notifications. [STANDARDS-TRACK] YANG is a data modeling language used to model configuration data, state data, Remote Procedure Calls, and notifications for network management protocols. This document describes the syntax and semantics of version 1.1 of the YANG language. YANG version 1.1 is a maintenance release of the YANG language, addressing ambiguities and defects in the original specification. There are a small number of backward incompatibilities from YANG version 1. This document also specifies the YANG mappings to the Network Configuration Protocol (NETCONF). This document captures the current syntax used in YANG module tree diagrams. The purpose of this document is to provide a single location for this definition. This syntax may be updated from time to time based on the evolution of the YANG language. This document defines an abstract (generic, or base) YANG data model for network/service topologies and inventories. The data model serves as a base model that is augmented with technology-specific details in other, more specific topology and inventory data models. As a complement to the Layer 3 Virtual Private Network Service Model (L3SM), which is used for communication between customers and service providers, this document defines an L3VPN Network Model (L3NM) that can be used for the provisioning of Layer 3 Virtual Private Network (L3VPN) services within a service provider network. The model provides a network-centric view of L3VPN services. The L3NM is meant to be used by a network controller to derive the configuration information that will be sent to relevant network devices. The model can also facilitate communication between a service orchestrator and a network controller/orchestrator. Huawei Technologies Huawei Technologies Ciena Juniper Networks China Mobile This document defines a YANG model for the IETF Network Slice service. The model can be used by an IETF Network Slice customer to manage IETF Network Slices. Samsung Electronics Huawei Technologies Huawei Technologies Huawei Technologies Ericsson Microsoft This document provides a YANG data model to map customer service models (e.g., L3VPN Service Delivery model) to Traffic Engineering (TE) models (e.g., the TE Tunnel or the Virtual Network (VN) model). These models are referred to as TE Service Mapping Model and are applicable generically to the operator's need for seamless control and management of their VPN services with underlying TE support. The models are principally used for monitoring and diagnostics of the management systems to show how the service requests are mapped onto underlying network resource and TE models. Orange Telefonica Telefonica Vodafone This document defines an L2VPN Network YANG Model (L2NM) which can be used to manage the provisioning of Layer 2 Virtual Private Network services within a network (e.g., service provider network). The L2NM complements the Layer 2 Service Model (L2SM) by providing a network- centric view of the service that is internal to a service provider. The L2NM is particularly meant to be used by a network controller to derive the configuration information that will be sent to relevant network devices. Also, this document defines a YANG module to manage Ethernet segments and the initial versions of two IANA-maintained modules that include a set of identities of BGP Layer 2 encapsulation types and pseudowire types. Huawei Technologies Huawei Technologies China Unicom This document defines a YANG data model for managing Network Resource Partition (NRP) topologies and associated resource allocation. The model can be used for the realization of IETF network slice services. RFC 2119 specifies common key words that may be used in protocol specifications. This document aims to reduce the ambiguity by clarifying that only UPPERCASE usage of the key words have the defined special meanings. Informative References Traffic Engineered (TE) networks have a variety of mechanisms to facilitate the separation of the data plane and control plane. They also have a range of management and provisioning protocols to configure and activate network resources. These mechanisms represent key technologies for enabling flexible and dynamic networking. The term "Traffic Engineered network" refers to a network that uses any connection-oriented technology under the control of a distributed or centralized control plane to support dynamic provisioning of end-to- end connectivity. Abstraction of network resources is a technique that can be applied to a single network domain or across multiple domains to create a single virtualized network that is under the control of a network operator or the customer of the operator that actually owns the network resources. This document provides a framework for Abstraction and Control of TE Networks (ACTN) to support virtual network services and connectivity services. Old Dog Consulting Juniper Networks Ciena NTT Futurewei Telefonica Microsoft Inc. This document describes network slicing in the context of networks built from IETF technologies. It defines the term "IETF Network Slice" and establishes the general principles of network slicing in the IETF context. The document discusses the general framework for requesting and operating IETF Network Slices, the characteristics of an IETF Network Slice, the necessary system components and interfaces, and how abstract requests can be mapped to more specific technologies. The document also discusses related considerations with monitoring and security. This document also provides definitions of related terms to enable consistent usage in other IETF documents that describe or use aspects of IETF Network Slices. Juniper Networks Juniper Networks Huawei Technologies Comcast Ericsson Ericsson ZTE Corporation ZTE Corporation Volta Networks Telefonica Ciena Verizon Realizing network slices may require the Service Provider to have the ability to partition a physical network into multiple logical networks of varying sizes, structures, and functions so that each slice can be dedicated to specific services or customers. Multiple network slices can be realized on the same network while ensuring slice elasticity in terms of network resource allocation. This document describes a scalable solution to realize network slicing in IP/MPLS networks by supporting multiple services on top of a single physical network by relying on compliant domains and nodes to provide forwarding treatment (scheduling, drop policy, resource usage) on to packets that carry identifiers that indicate the slicing service that is to be applied to the packets.

Acknowledgments Thanks to Jie Dong for the initial discussion behind this document.

Examples TO be added in future revisions.