A YANG Data Model for Network Resource Partition (NRP)
draft-wd-teas-nrp-yang-01
The information below is for an old version of the document.
| Document | Type |
This is an older version of an Internet-Draft whose latest revision state is "Replaced".
|
|
|---|---|---|---|
| Authors | Bo Wu , Dhruv Dhody , Ying Cheng | ||
| Last updated | 2022-07-11 | ||
| Replaces | draft-wd-teas-vtn-network-yang | ||
| Replaced by | draft-wdbsp-teas-nrp-yang | ||
| RFC stream | (None) | ||
| Formats | |||
| Stream | Stream state | (No stream defined) | |
| Consensus boilerplate | Unknown | ||
| RFC Editor Note | (None) | ||
| IESG | IESG state | I-D Exists | |
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| Send notices to | (None) |
draft-wd-teas-nrp-yang-01
Network Working Group B. Wu
Internet-Draft D. Dhody
Intended status: Standards Track Huawei Technologies
Expires: 12 January 2023 Y. Cheng
China Unicom
11 July 2022
A YANG Data Model for Network Resource Partition (NRP)
draft-wd-teas-nrp-yang-01
Abstract
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.
Status of This Memo
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provisions of BCP 78 and BCP 79.
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material or to cite them other than as "work in progress."
This Internet-Draft will expire on 12 January 2023.
Copyright Notice
Copyright (c) 2022 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.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 2
2.1. Tree Diagrams . . . . . . . . . . . . . . . . . . . . . . 3
3. NRP modelling requirements . . . . . . . . . . . . . . . . . 3
4. NRP Modelling Consideration . . . . . . . . . . . . . . . . . 4
4.1. NRP Model Usage example . . . . . . . . . . . . . . . . . 6
4.2. NRP Modeling Design . . . . . . . . . . . . . . . . . . . 7
5. Description of NRP YANG Module . . . . . . . . . . . . . . . 9
6. NRP Yang Module Tree . . . . . . . . . . . . . . . . . . . . 10
7. NRP Yang Module . . . . . . . . . . . . . . . . . . . . . . . 12
8. Security Considerations . . . . . . . . . . . . . . . . . . . 23
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 23
10. Contributor . . . . . . . . . . . . . . . . . . . . . . . . . 24
11. References . . . . . . . . . . . . . . . . . . . . . . . . . 24
11.1. Normative References . . . . . . . . . . . . . . . . . . 24
11.2. Informative References . . . . . . . . . . . . . . . . . 26
Appendix A. An Example . . . . . . . . . . . . . . . . . . . . . 27
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 32
1. Introduction
[I-D.ietf-teas-ietf-network-slices] 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 network
resource partition (NRP) to host one or a group of network slice
services according to characteristics including SLOs and SLEs.
[I-D.dong-teas-nrp-scalability] analyzes the scalability issues of
network slice services in detail and suggests candidate technologies
of control and forwarding planes of the NRP.
This document defines a YANG model of NRP that the IETF NSC (Network
Slice controller) can use to manage NRP instances to realize the
network slicing services. According to the YANG model classification
of [RFC8309], the NRP model is a network configuration model.
2. Terminology
The following terms are defined in [RFC6241] and are used in this
specification:
* configuration data
* state data
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The following terms are defined in [RFC7950] and are used in this
specification:
* augment
* data model
* data node
The terminology for describing YANG data models is found in
[RFC7950].
2.1. Tree Diagrams
The tree diagram used in this document follows the notation defined
in [RFC8340].
3. NRP modelling requirements
[I-D.ietf-teas-ietf-network-slices] section 6.1 introduces the
concept of NRP, which is a collection of resources (bufferage,
queuing, scheduling, etc.) in the underlay network to provide
specific SLOs and SLEs for connectivity constructs of IETF Network
Slice services. [I-D.ietf-teas-ns-ip-mpls] provides some solutions
to realize network slicing in IP/MPLS networks.
[I-D.dong-teas-nrp-scalability] provides analysis and possible
optimizations of the control plane and data plane of NRP in IP/MPLS
networks for better scalability. The following are some common NRP
attributes for NRP management identified based on the analysis:
* NRP instantiation
- NRP partition type: Refers to various NRP resource partition
methods, such as control plane partition, data plane partition,
no partition, etc.
- NRP topology generation method: Topologies can be created using
multiple methods. For example, NRP links can be all links in
the native topology, or explicitly selected links from native
topology or implicitly selected from the various existing
topologies.
- NRP resource reservation: Reserves link resources for the NRP.
- NRP control plane: Mechanisms that provide routing and
forwarding to one or a group of network slice traffic to ensure
the corresponding SLO and SLE through NRP link resources.
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- NRP data plane: Dataplane identifier carried in a data packet,
which is used to mark the link resources and behaviors
allocated to the NRP.
- NRP steering policy: Policies for steering slice traffic to the
NRP.
* NRP modification or updates: Modifications or additions to
existing NRP-allocated resources, e.g. some congested links need
to be expanded.
* NRP monitoring: NRP-allocated resources, including NRP-specific
link or node SID, link bandwidth usage, link delay, and packet
loss status, etc.
4. NRP Modelling Consideration
An NRP is a subset, or all, of resources allocated from a physical
network or logical network. Depending on the SLO and SLE
requirements of the slicing service and also the available resources
of the operator's network, there are several options of creating an
NRP. One option is that each physical link is allocated to only one
specific NRP, and different NRPs do not share any physical link. One
more typical option is that multiple NRPs share the same physical
links, and each NRP is built with virtual links with a certain subset
of the bandwidth available on the physical links to provide network
resource isolation.
In addition to specifying resource allocation from the underlay
network, An NRP also needs to have associated control plane and
forwarding plane technologies, which can provide specific routing and
forwarding so that the traffic received from NRP edge nodes that is
characterized to match the NRP traffic classification rule is
constrained to the NRP exclusive topology and resource allocation.
The NRP allows network operators to manage the resources of IETF
network slices which are used to provide network slice service
traffic with specific SLOs and SLEs.
As defined in [I-D.dong-teas-nrp-scalability], the draft discusses
NRP control plane and data plane requirements in different
provisioning scenarios, and describes that the NRP control plane is
used to exchange network resource attributes and associated logical
topology information between nodes of the NRP so that NRP-specific
routing and forwarding tables could be generated. For the NRP
control plane, distributed control plane mechanism, such as Multi-
topology, Flex-Algo or centralized SDN or hybrid combination could be
defined. To help with forwarding entries, several data-plane
encapsulation options are also discussed to carry NRP information in
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the NRP traffic packets. The example NRP data plane identifier could
be the IPv6 addresses or the MPLS forwarding labels or dedicated NRP
data-plane identifiers.
An example of NRP instances and a physical network is illustrated in
Figure 1. In the example, each NRP instance has a customized network
topology comprised of a set of links and nodes in the physical
network. In control plane, each NRP could be associated with a
multi-topology or a Flex-Algo. And it also has its own forwarding
plane resources and identifiers which provide NRP-specific packet
forwarding.
++++ ++++ ++++
+--+===+--+===+--+
+--+===+--+===+--+
++++ +++\\ ++++
|| || \\ || Physical
|| || \\ || Network
++++ ++++ ++++ \\+++ ++++
+ +===+--+===+--+===+--+===+ +
+ +===+--+===+--+===+--+===+ +
++++ ++++ ++++ ++++ ++++
PE1 PE2
|
\|/
o----o-----o
/ / NRP-1
o-----o-----o----o----o
o----o
/ / \ NRP-2
o-----o----o---o------o
...
o----o
/ / NPR-n
o-----o----o----o-----o
o is a virtual node
--- is a virtual link
Figure 1: An NRP Example
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[I-D.ietf-teas-ietf-network-slices] also describes the management of
the NRP. After an NRP created, the NRP may need to be refined and
modified as the network status and slice services change, and could
be extended if necessary to meet the customers' demands. In addition
to configuration management, the NRP should also provide detailed
monitoring information about underlying resources to further provide
monitoring for the hosted slice services.
4.1. NRP Model Usage example
One major application of network slices is 5G services. Figure 2
shows the use of the NRP model to realize the IETF Network Slice for
the 5G use case, based on the reference framework defined in
[I-D.ietf-teas-ietf-network-slices]. The figure shows that the NSC
uses the L3VPN network model [I-D.ietf-opsawg-l3sm-l3nm] to map to an
IETF Network Slice service and uses the NRP model to map VPN traffic
to underlying network resources, so that the SLO and SLE required by
the IETF network slice service are ensured when the VPN service
traverses the underlying network.
+------------------------------------------+
| Customer |
| |
+------------------------------------------+
A
| IETF Network slice service interface
V
+------------------------------------------+
| IETF Network Slice Controller (NSC) |
+------------------------------------------+
A
L3NM | Network Configuration Interface
V NRP Model
+------------------------------------------+
| Network Controller(s) |
+------------------------------------------+
A
| Device model
V
+------------------------------------------------+
Network
Figure 2: Reference Module Use Case
In the process of realizing an IETF network slice service, the NSC
can use a static NRP instance or dynamically create one as one or a
group of VPNs underlay construct. Compared with existing VPN
underlying built with full mesh tunneling mechanisms, the NRP could
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provide resource isolation, topology constraints, and simplified
configuration. Additionally, specific service flows of a VPN can be
further optimized using SR policies defined in
[I-D.dong-idr-sr-policy-vtn].
4.2. NRP Modeling Design
As defined in [I-D.ietf-teas-ietf-network-slices], a network resource
partition (NRP) is a collection of resources in the underlay network.
An NRP can have a dedicated topology or can use a shared topology
with other NRPs.
Therefore, an NRP is modeled as network topology defined in [RFC8345]
with augmentations. A new network type "nrp" is defined. A network
topology data instance containing the nrp network type, indicates an
NRP instance. The Figure 3 shows the relationship between this
module and other topology modules.
+-----------------------+
|Network Topology Model |
| RFC8345 |
+-----------------------+
|
+-------------+-------------+-------------+
| | | |
V V V V
+----------+ ............ ............ ............
| Network | : L3 : : TE : : L2 :
| Resource | :Topology : : Topology : : Topology :
| Partition| : Model : : Model : : Model :
| Model | :..........: :..........: :..........:
+----------+
Figure 3: NRP Model Relationship
The container "nrp" under 'network' of [RFC8345] defines global
parameters for an NRP, which defines NRP partition type, NRP topology
generation method, and the specific control plane and data plane
mechanisms of an NRP. And also, the traffic steering policy of the
NRP may include a dynamic color based policies or an ACL-based static
ones.
The NRP partition type is used to describe multiple NRP resource
partition methods, for example, no partition, control plane resource
partition, data plane resource partition, or a combination of two
types.
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As an NRP may consist of the entire or a subset of links in the
underlay network, there are various methods to generate NRP topology,
which include:
The NRP with a subset of links in the underlay network, which has
the same topology as the pre-built L3 topology, MT topology,
flexalgo, or TE topology, and also has the same resource
reservation requirements. The topology definition may come
directly from the topology defined by "control plane".
For other NRPs that require a dedicated topology, "nrp-topology-
group" is used to configure the selected links from the base
topology. Generally, the base topology refers to the underlay
network topology. An NRP can be configured with one or more "nrp-
topology-group" to create topology resources required by the NRP.
For example, if an NRP needs to reserve the same bandwidth for a
groups of links, the same "group-id" can be assigned to the links
and "bandwidth-reservation" is specified, such as access network
link group, aggregation network link group, etc. If some inter-
domain links, have multiple bandwidth reservation requirements,
they can also be classified into a group. Then, each link can
override the bandwidth reservation of the group bandwidth
reservation.
As discussed in [I-D.dong-teas-nrp-scalability], an NRP could have
multiple control plane implementation options. For a better network
scalability, an NRP does not require an independent distributed
control protocol instance or a independent centralized control plane
instance, that is, multiple NRPs can share a same control plane
instance. Thus, an NRP can use a predefined native or abstract TE
topology by referring to a TE network instance or a predefined
control protocol instance by referring to Layer3 network instance.
In addition to global NRP parameters, each NRP instance also consists
of a set of nodes and a set of links, which have different attributes
that represent the allocated resources or the operational status of
the NRP. An NRP could support several data plane resource partition
methods, which are defined by 'link-partition-type'' under an NRP
link, which can further be supported by FlexE or independent queue
techniques.
There are multiple modes of NRP operations to be supported as
follows:
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* NRP instantiation: Depending on the slice services types and also
network status, there can be two types of approaches. One method
is to create an NRP instance before the network controller
processes the IETF network slice service request. Another one is
that the network controller may start creating an NRP instance
while configuring the IETF network slice service request.
* NRP modification: When the capacity of an existing NPR link is
close to capacity, the bandwidth of the link could be increased.
And when the NRP link or node resources are insufficient, new NRP
links and nodes could be added.
* NRP Deletion: If the NSC determines that no slice service is using
an NRP, the NSC can delete the NRP instance.
* NRP Monitoring: The NSC can use the NRP model to track and monitor
NRP resource status and usage.
5. Description of NRP YANG Module
The description of the NRP data nodes are as follows:
* "nrp-id": Is an identifier that is used to uniquely identify an
NRP instance within the network scope.
* NRP partition type: Refers to control plane resource partition,
data plane resource partition, or a combination of two types.
* NRP resources reservation: The nodes and links represent the
network resource allocated for an NRP instance. 'bandwidth-
reservation' specifies the bandwidth allocated to an NRP instance,
or is overridden by the configuration of the NRP link. 'link-
partition-type' specifies the resource partition types of the
physical interfaces associated with an NRP link.
* NRP control plane: When an NRP shares an IGP instance or TE
instance with other NRPs, "igp-topology-ref" or "te-topology-
identifier" is used to refer to the existing IGP network instance
or TE instance. And an NRP can further use Multi-Topology Routing
(MTR) or Flex-algo to refer to the IGP instance to generate its
own NRP-specific forwarding tables. Multi-Topology Routing (MTR)
is defined in [RFC4915], [RFC5120], and
[I-D.ietf-lsr-isis-sr-vtn-mt] or Flex-algo is defined in
[I-D.ietf-lsr-flex-algo].
* NRP data plane: Defines the data plane mechanism and the NRP
identifier of the network domain managed by the network
controller. The data plane mechanism could be based on MPLS or
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IPv6 forwarding. The container "data plane" is used to specify
the NRP data plane encapsulation types and values that are used to
identify NRP-specific network resources. The NRP data plane
identifier is defined in [I-D.ietf-spring-sr-for-enhanced-vpn]
and[I-D.dong-6man-enhanced-vpn-vtn-id].
* NRP steering policy: The leaf-list "color-id" is used for dynamic
traffic steering based on SR policy of an NRP and The leaf-list
"acl-ref" is used for common traffic steering.
* NRP topology group: The list "nrp-topology-group" is used to
explicitly select subset of links of a underlay topology.
6. NRP Yang Module Tree
module: ietf-nrp
augment /nw:networks/nw:network/nw:network-types:
+--rw nrp!
augment /nw:networks/nw:network:
+--rw nrp
+--rw nrp-id? uint32
+--rw nrp-name? string
+--rw partition-type? identityref
+--rw bandwidth-reservation
| +--rw (bandwidth-type)?
| +--:(bandwidth-value)
| | +--rw bandwidth-value? uint64
| +--:(bandwidth-percentage)
| +--rw bandwidth-percent? rt-types:percentage
+--rw control-plane
| +--rw topology-ref
| +--rw igp-topology-ref
| | +--rw network-ref?
| | | -> /nw:networks/network/network-id
| | +--rw multi-topology-id? uint32
| | +--rw flex-algo-id? uint32
| +--rw te-topology-identifier
| +--rw provider-id? te-global-id
| +--rw client-id? te-global-id
| +--rw topology-id? te-topology-id
+--rw data-plane
| +--rw global-resource-identifier
| | +--rw nrp-dataplane-ipv6-type
| | | +--rw nrp-dp-value? inet:ipv6-address
| | +--rw nrp-dataplane-mpls-type
| | +--rw nrp-dp-value? uint32
| +--rw nrp-aware-dp
| +--rw nrp-aware-srv6-type!
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| +--rw nrp-aware-sr-mpls-type!
+--rw steering-policy
| +--rw color-id* uint32
| +--rw acl-ref* -> /acl:acls/acl/name
+--rw nrp-topology-group* [group-id]
+--rw group-id string
+--rw base-topology-ref
| +--rw network-ref? -> /nw:networks/network/network-id
+--rw links* [link-ref]
| +--rw link-ref leafref
| +--rw link-attributes-override
| +--rw bandwidth-reservation
| +--rw (bandwidth-type)?
| +--:(bandwidth-value)
| | +--rw bandwidth-value? uint64
| +--:(bandwidth-percentage)
| +--rw bandwidth-percent?
| rt-types:percentage
+--rw bandwidth-reservation
+--rw (bandwidth-type)?
+--:(bandwidth-value)
| +--rw bandwidth-value? uint64
+--:(bandwidth-percentage)
+--rw bandwidth-percent? rt-types:percentage
augment /nw:networks/nw:network/nw:node:
+--ro nrp
+--ro nrp-aware-dp-id
+--ro nrp-dp-srv6? srv6-types:srv6-sid
+--ro nrp-dp-sr-mpls? rt-types:mpls-label
augment /nw:networks/nw:network/nt:link:
+--rw nrp
+--rw bandwidth-reservation
| +--rw (bandwidth-type)?
| +--:(bandwidth-value)
| | +--rw bandwidth-value? uint64
| +--:(bandwidth-percentage)
| +--rw bandwidth-percent? rt-types:percentage
+--rw partition-type? identityref
+--ro nrp-aware-dp-id
| +--ro nrp-dp-srv6? srv6-types:srv6-sid
| +--ro nrp-dp-sr-mpls? rt-types:mpls-label
+--ro statistics
+--ro admin-status?
| te-types:te-admin-status
+--ro oper-status?
| te-types:te-oper-status
+--ro one-way-available-bandwidth?
| rt-types:bandwidth-ieee-float32
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+--ro one-way-utilized-bandwidth?
| rt-types:bandwidth-ieee-float32
+--ro one-way-min-delay? uint32
+--ro one-way-max-delay? uint32
+--ro one-way-delay-variation? uint32
+--ro one-way-packet-loss? decimal64
7. NRP Yang Module
<CODE BEGINS> file "ietf-nrp@2022-07-11.yang"
module ietf-nrp {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-nrp";
prefix nrp;
import ietf-network {
prefix nw;
reference
"RFC 8345: A YANG Data Model for Network Topologies";
}
import ietf-network-topology {
prefix nt;
reference
"RFC 8345: A YANG Data Model for Network Topologies";
}
import ietf-routing-types {
prefix rt-types;
reference
"RFC 8294: Common YANG Data Types for the Routing Area";
}
import ietf-te-types {
prefix te-types;
reference
"RFC 8776: Traffic Engineering Common YANG Types";
}
import ietf-te-packet-types {
prefix te-packet-types;
reference
"RFC 8776: Traffic Engineering Common YANG Types";
}
import ietf-srv6-types {
prefix srv6-types;
}
import ietf-inet-types {
prefix inet;
reference
"RFC 6991: Common YANG Data Types";
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}
import ietf-access-control-list {
prefix acl;
reference
"RFC 8519: YANG Data Model for Network Access Control Lists
(ACLs)";
}
organization
"IETF TEAS Working Group";
contact
"
WG Web: <http://tools.ietf.org/wg/teas/>
WG List:<mailto:teas@ietf.org>
Editor: Bo Wu <lana.wubo@huawei.com>
: Dhruv Dhody <dhruv.ietf@gmail.com>";
description
"This YANG module defines a network data module for
NRP(Network Resource Partition).
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
(https://www.rfc-editor.org/info/rfcXXXX); see the RFC itself
for full legal notices.";
revision 2022-07-11 {
description
"This is the initial version of NRP YANG model.";
reference
"RFC XXX: A YANG Data Model for Network Resource Partition";
}
identity nrp-partition-type {
description
"Base identity for NRP partition type.";
}
identity nrp-control-plane-partition {
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base nrp-partition-type;
description
"Identity for control plane partition.";
}
identity nrp-data-plane-partition {
base nrp-partition-type;
description
"Identity for data plane partition.";
}
identity nrp-hybrid-plane-partition {
base nrp-partition-type;
description
"Identity for both planes partition.";
}
identity nrp-no-partition {
base nrp-partition-type;
description
"Identity for no partition.";
}
identity nrp-link-partition-type {
description
"Base identity for interface partition type.";
}
identity virtual-sub-interface-partition {
base nrp-link-partition-type;
description
"Identity for virtual interface or sub-interface, e.g. FlexE.";
}
identity queue-partition {
base nrp-link-partition-type;
description
"Identity for queue partition type.";
}
identity nrp-dataplane-type {
description
"Base identity for NRP data plane type.";
}
identity nrp-dataplane-ipv6 {
base nrp-dataplane-type;
description
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"Identity for NRP specific packet forwarding of IPv6.";
}
identity nrp-dataplane-mpls {
base nrp-dataplane-type;
description
"Identity for NRP specific packet forwarding of MPLS.";
}
identity nrp-dataplane-sr-mpls {
base nrp-dataplane-type;
description
"Identity for NRP specific packet forwarding of SR MPLS.";
}
identity nrp-dataplane-srv6 {
base nrp-dataplane-type;
description
"Identity for NRP specific packet forwarding of SRv6.";
}
/*
* Groupings
*/
grouping nrp-bandwidth-reservation {
description
"Grouping for NRP bandwidth reservation.";
container bandwidth-reservation {
description
"Container for NRP bandwidth reservation.";
choice bandwidth-type {
description
"Choice of bandwidth reservation type.";
case bandwidth-value {
leaf bandwidth-value {
type uint64;
units "bps";
description
"Bandwidth allocation for the NRP as absolute value.";
}
}
case bandwidth-percentage {
leaf bandwidth-percent {
type rt-types:percentage;
description
"Bandwidth allocation for the NRP as a percentage
of a link.";
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}
}
}
}
}
grouping nrp-control-plane-attributes {
description
"Grouping for NRP control plane attributes.";
container control-plane {
description
"The container of NRP control plane mechanisms.";
container topology-ref {
description
"Container for topology reference.";
container igp-topology-ref {
description
"Container for IGP topology reference.";
uses nw:network-ref;
leaf multi-topology-id {
type uint32;
description
"The MT-id of an NRP.";
}
leaf flex-algo-id {
type uint32;
description
"The flex-algo-id of an NRP.";
}
}
uses te-types:te-topology-identifier;
}
}
}
grouping nrp-data-plane-attributes {
description
"Grouping for NRP data plane attributes.";
container data-plane {
description
"The data plane mechanisms of an NRP. The forwarding plane
could be MPLS, IPv6, SRv6, or SR-MPLS.";
container global-resource-identifier {
description
"The container of global NRP data-plane ID.";
container nrp-dataplane-ipv6-type {
description
"The container of IPv6 based NRP data-plane identifier.";
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leaf nrp-dp-value {
type inet:ipv6-address;
description
"Indicates the IPv6 NRP data-plane identifier.";
}
}
container nrp-dataplane-mpls-type {
description
"The container of MPLS based NRP data-plane identifier.";
leaf nrp-dp-value {
type uint32;
description
"Indicates MPLS metadata values to identify MPLS NRP
data plane identifier, e.g. Ancillary data.";
}
}
}
container nrp-aware-dp {
description
"The container of SR based NRP data-plane identifier.";
container nrp-aware-srv6-type {
presence "Enables SRv6 data plane type.";
description
"The container of SRv6 based NRP data-plane identifier.";
}
container nrp-aware-sr-mpls-type {
presence "Enables SR MPLS data plane type.";
description
"The container of SR MPLS based NRP data-plane identifier.";
}
}
}
}
grouping nrp-traffic-steering-policy {
description
"The grouping of the NRP traffic steering policy.";
container steering-policy {
description
"The container of a policy set
matching an NRP traffic classifier.";
leaf-list color-id {
type uint32;
description
"A list of color ID for NRP traffic steering based on
SR policy.";
}
leaf-list acl-ref {
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type leafref {
path "/acl:acls/acl:acl/acl:name";
}
description
"A list of ACL for NRP traffic classification.";
}
}
}
grouping nrp-aware-id {
description
"The grouping of NRP aware dataplane ID.";
container nrp-aware-dp-id {
config false;
description
"The container of NRP data plane identifier.";
leaf nrp-dp-srv6 {
type srv6-types:srv6-sid;
description
"Indicates the SRv6 SID value as the NRP data plane
identifier.";
}
leaf nrp-dp-sr-mpls {
type rt-types:mpls-label;
description
"Indicates the SR MPLS ID value as the NRP data plane
identifier.";
}
}
}
grouping nrp-topology-attributes {
description
"NRP global attributes.";
container nrp {
description
"Containing NRP topology attributes.";
leaf nrp-id {
type uint32;
description
"NRP identifier.";
}
leaf nrp-name {
type string;
description
"NRP Name.";
}
leaf partition-type {
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type identityref {
base nrp-partition-type;
}
default "nrp-no-partition";
description
"Indicates the resource partition type of the NRP, such as
control plane partition, data plane partition,
or no partition.";
}
uses nrp-bandwidth-reservation;
uses nrp-control-plane-attributes;
uses nrp-data-plane-attributes;
uses nrp-traffic-steering-policy;
list nrp-topology-group {
key "group-id";
description
"List of groups for NRP topology elements (node or links)
that share common attributes.";
leaf group-id {
type string;
description
"The NRP topology group identifier.";
}
container base-topology-ref {
description
"Container for the base topology reference.";
uses nw:network-ref;
}
list links {
key "link-ref";
description
"A list of links with common attributes";
leaf link-ref {
type leafref {
path
"/nw:networks/nw:network[nw:network-id=current()"
+ "/../../base-topology-ref/network-ref]"
+ "/nt:link/nt:link-id";
}
description
"A reference to a link in the base topology.";
}
container link-attributes-override {
description
"Container for overriding link attributes,
e.g. resource reservation.";
uses nrp-bandwidth-reservation;
}
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}
uses nrp-bandwidth-reservation;
}
}
// nrp
}
// nrp-node-attributes
grouping nrp-node-attributes {
description
"NRP node scope attributes.";
container nrp {
config false;
description
"Containing NRP attributes.";
uses nrp-aware-id;
}
}
// nrp-node-attributes
grouping nrp-link-states {
description
"NRP link scope states.";
container nrp {
description
"Containing NRP attributes.";
uses nrp-bandwidth-reservation;
leaf partition-type {
type identityref {
base nrp-partition-type;
}
description
"Indicates the resource partition type of a link.";
}
uses nrp-aware-id;
uses nrp-statistics-per-link;
}
}
// one-way-performance-metrics
grouping one-way-performance-bandwidth {
description
"Grouping for one-way performance bandwidth.";
leaf one-way-available-bandwidth {
type rt-types:bandwidth-ieee-float32;
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units "bytes per second";
default "0x0p0";
description
"Available bandwidth that is defined to be NRP link
bandwidth minus bandwidth utilization. For a
bundled link, available bandwidth is defined to be the
sum of the component link available bandwidths.";
}
leaf one-way-utilized-bandwidth {
type rt-types:bandwidth-ieee-float32;
units "bytes per second";
default "0x0p0";
description
"Bandwidth utilization that represents the actual
utilization of the link (i.e. as measured in the router).
For a bundled link, bandwidth utilization is defined to
be the sum of the component link bandwidth
utilizations.";
}
}
// nrp-link-statistics
grouping nrp-statistics-per-link {
description
"Statistics attributes per NRP link.";
container statistics {
config false;
description
"Statistics for NRP link.";
leaf admin-status {
type te-types:te-admin-status;
description
"The administrative state of the link.";
}
leaf oper-status {
type te-types:te-oper-status;
description
"The current operational state of the link.";
}
uses one-way-performance-bandwidth;
uses te-packet-types:one-way-performance-metrics-packet;
}
}
grouping nrp-augment {
description
"Augmentation for NRPs.";
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container nrp {
presence "NRP support";
description
"Indicates NRP support.";
}
// nrp
}
// nrp-augment
augment "/nw:networks/nw:network/nw:network-types" {
description
"Defines the NRP topology type.";
container nrp {
presence "Indicates NRP topology";
description
"The presence identifies the NRP type.";
}
}
augment "/nw:networks/nw:network" {
when 'nw:network-types/nrp:nrp' {
description
"Augment only for NRP topology.";
}
description
"Augment NRP configuration and state.";
uses nrp-topology-attributes;
}
augment "/nw:networks/nw:network/nw:node" {
when '../nw:network-types/nrp:nrp' {
description
"Augment only for NRP topology.";
}
description
"Augment node configuration and state.";
uses nrp-node-attributes;
}
augment "/nw:networks/nw:network/nt:link" {
when '../nw:network-types/nrp:nrp' {
description
"Augment only for NRP topology.";
}
description
"Augment link configuration and state.";
uses nrp-link-states;
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}
}
<CODE ENDS>
8. Security Considerations
The YANG module defined in this document 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.
nrp-link: A malicious client could attempt to remove a link from a
topology, add a new link. In each case, the structure of the
topology would be sabotaged, and this scenario could, for example,
result in an NRP topology that is less than optimal.
The entries in the nodes above include the whole network
configurations corresponding with the NRP, and indirectly create or
modify the PE or P device configurations. Unexpected changes to
these entries could lead to service disruption and/or network
misbehavior.
9. IANA Considerations
This document registers a URI in the IETF XML registry [RFC3688].
Following the format in [RFC3688], the following registration is
requested to be made:
URI: urn:ietf:params:xml:ns:yang:ietf-nrp
Registrant Contact: The IESG.
XML: N/A, the requested URI is an XML namespace.
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This document requests to register a YANG module in the YANG Module
Names registry [RFC7950].
Name: ietf-nrp
Namespace: urn:ietf:params:xml:ns:yang:ietf-nrp
Prefix: nrp
Reference: RFC XXXX
10. Contributor
Zhenbin Li
Huawei
Email: lizhenbin@huawei.com
Jie Dong
Huawei
Email: jie.dong@huawei.com
11. References
11.1. Normative References
[I-D.dong-6man-enhanced-vpn-vtn-id]
Dong, J., Li, Z., Xie, C., Ma, C., and G. Mishra,
"Carrying Virtual Transport Network (VTN) Identifier in
IPv6 Extension Header", Work in Progress, Internet-Draft,
draft-dong-6man-enhanced-vpn-vtn-id-06, 24 October 2021,
<https://www.ietf.org/archive/id/draft-dong-6man-enhanced-
vpn-vtn-id-06.txt>.
[I-D.dong-idr-sr-policy-vtn]
Dong, J., Hu, Z., and R. Pang, "BGP SR Policy Extensions
for Virtual Transport Network", Work in Progress,
Internet-Draft, draft-dong-idr-sr-policy-vtn-01, 11 July
2021, <https://www.ietf.org/archive/id/draft-dong-idr-sr-
policy-vtn-01.txt>.
[I-D.ietf-lsr-flex-algo]
Psenak, P., Hegde, S., Filsfils, C., Talaulikar, K., and
A. Gulko, "IGP Flexible Algorithm", Work in Progress,
Internet-Draft, draft-ietf-lsr-flex-algo-20, 18 May 2022,
<https://www.ietf.org/archive/id/draft-ietf-lsr-flex-algo-
20.txt>.
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[I-D.ietf-lsr-isis-sr-vtn-mt]
Xie, C., Ma, C., Dong, J., and Z. Li, "Using IS-IS Multi-
Topology (MT) for Segment Routing based Virtual Transport
Network", Work in Progress, Internet-Draft, draft-ietf-
lsr-isis-sr-vtn-mt-03, 10 July 2022,
<https://www.ietf.org/archive/id/draft-ietf-lsr-isis-sr-
vtn-mt-03.txt>.
[I-D.ietf-spring-sr-for-enhanced-vpn]
Dong, J., Bryant, S., Miyasaka, T., Zhu, Y., Qin, F., Li,
Z., and F. Clad, "Segment Routing based Virtual Transport
Network (VTN) for Enhanced VPN", Work in Progress,
Internet-Draft, draft-ietf-spring-sr-for-enhanced-vpn-02,
5 March 2022, <https://www.ietf.org/archive/id/draft-ietf-
spring-sr-for-enhanced-vpn-02.txt>.
[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
DOI 10.17487/RFC3688, January 2004,
<https://www.rfc-editor.org/info/rfc3688>.
[RFC4915] Psenak, P., Mirtorabi, S., Roy, A., Nguyen, L., and P.
Pillay-Esnault, "Multi-Topology (MT) Routing in OSPF",
RFC 4915, DOI 10.17487/RFC4915, June 2007,
<https://www.rfc-editor.org/info/rfc4915>.
[RFC5120] Przygienda, T., Shen, N., and N. Sheth, "M-ISIS: Multi
Topology (MT) Routing in Intermediate System to
Intermediate Systems (IS-ISs)", RFC 5120,
DOI 10.17487/RFC5120, February 2008,
<https://www.rfc-editor.org/info/rfc5120>.
[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>.
[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>.
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[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>.
[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>.
[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>.
[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>.
[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>.
[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>.
11.2. Informative References
[I-D.dong-teas-nrp-scalability]
Dong, J., Li, Z., Gong, L., Yang, G., Guichard, J. N.,
Mishra, G., Qin, F., Saad, T., and V. P. Beeram,
"Scalability Considerations for Network Resource
Partition", Work in Progress, Internet-Draft, draft-dong-
teas-nrp-scalability-02, 16 May 2022,
<https://www.ietf.org/archive/id/draft-dong-teas-nrp-
scalability-02.txt>.
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[I-D.ietf-opsawg-l3sm-l3nm]
Barguil, S., Dios, O. G. D., Boucadair, M., Munoz, L. A.,
and A. Aguado, "A YANG Network Data Model for Layer 3
VPNs", Work in Progress, Internet-Draft, draft-ietf-
opsawg-l3sm-l3nm-18, 8 October 2021,
<https://www.ietf.org/archive/id/draft-ietf-opsawg-l3sm-
l3nm-18.txt>.
[I-D.ietf-teas-ietf-network-slices]
Farrel, A., Drake, J., Rokui, R., Homma, S., Makhijani,
K., Contreras, L. M., and J. Tantsura, "Framework for IETF
Network Slices", Work in Progress, Internet-Draft, draft-
ietf-teas-ietf-network-slices-12, 30 June 2022,
<https://www.ietf.org/archive/id/draft-ietf-teas-ietf-
network-slices-12.txt>.
[I-D.ietf-teas-ns-ip-mpls]
Saad, T., Beeram, V. P., Dong, J., Wen, B., Ceccarelli,
D., Halpern, J., Peng, S., Chen, R., Liu, X., Contreras,
L. M., Rokui, R., and L. Jalil, "Realizing Network Slices
in IP/MPLS Networks", Work in Progress, Internet-Draft,
draft-ietf-teas-ns-ip-mpls-00, 16 June 2022,
<https://www.ietf.org/archive/id/draft-ietf-teas-ns-ip-
mpls-00.txt>.
Appendix A. An Example
This section contains an example of an instance data tree in JSON
encoding [RFC7951]. The example instantiates ietf-nrp for the
topology that is depicted in the following diagram. There are three
nodes, D1, D2, and D3. D1 has three termination points, 1-0-1,
1-2-1, and 1-3-1. D2 has three termination points as well, 2-1-1,
2-0-1, and 2-3-1. D3 has two termination points, 3-1-1 and 3-2-1.
In addition there are six links, two between each pair of nodes with
one going in each direction.
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+------------+ +------------+
| D1 | | D2 |
/-\ /-\ /-\ /-\
| | 1-0-1 | |---------------->| | 2-1-1 | |
| | 1-2-1 | |<----------------| | 2-0-1 | |
\-/ 1-3-1 \-/ \-/ 2-3-1 \-/
| /----\ | | /----\ |
+---| |---+ +---| |---+
\----/ \----/
| | | |
| | | |
| | | |
| | +------------+ | |
| | | D3 | | |
| | /-\ /-\ | |
| +----->| | 3-1-1 | |-------+ |
+---------| | 3-2-1 | |<---------+
\-/ \-/
| |
+------------+
Figure 4: An NRP Instance Example
The corresponding NRP instance data tree is depicted below:
{
"ietf-network:networks": {
"network": [
{
"network-types": {
"ietf-nrp:nrp": {}
},
"network-id": "nrp-example",
"ietf-nrp:nrp": {
"nrp-id": "1",
"nrp-name": "NRP1",
"partition-type": "nrp-data-plane-partition",
"bandwidth-reservation": {
"bandwidth-value": "10000"
},
"control-plane": {
"topology-ref": {
"igp-topology-ref": {
" network-ref": "L3-topology-1",
" flex-algo-id": "129"
}
}
},
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"data-plane": {
"global-resource-identifier": {
"nrp-dataplane-ipv6-type": {
" nrp-dp-value:": "100"
}
}
},
"steering-policy": {
"color-id": "100"
},
"nrp-topology-group": [
{
"group-id": "group1",
"base-topology-ref": {
"network-ref": "native-topology"
}
}
]
},
"node": [
{
"node-id": "D1",
"termination-point": [
{
"tp-id": "1-0-1"
},
{
"tp-id": "1-2-1"
},
{
"tp-id": "1-3-1"
}
]
},
{
"node-id": "D2",
"termination-point": [
{
"tp-id": "2-0-1"
},
{
"tp-id": "2-1-1"
},
{
"tp-id": "2-3-1"
}
]
},
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{
"node-id": "D3",
"termination-point": [
{},
{
"tp-id": "3-2-1"
}
]
}
],
"ietf-network-topology:link": [
{
"link-id": "D1,1-2-1,D2,2-1-1",
"source": {
"source-node": "D1",
"source-tp": "1-2-1"
},
"destination": {
"dest-node": "D2",
"dest-tp": "2-1-1"
},
"ietf-nrp:nrp": {
"partition-type": "virtual-sub-interface-partition",
"bandwidth-reservation": {
"bandwidth-value": "10000"
}
}
},
{
"link-id": "D2,2-1-1,D1,1-2-1",
"source": {
"source-node": "D2",
"source-tp": "2-1-1"
},
"destination": {
"dest-node": "D1",
"dest-tp": "1-2-1"
},
"ietf-nrp:nrp": {
"partition-type": "virtual-sub-interface-partition",
"bandwidth-reservation": {
"bandwidth-value": "10000"
}
}
},
{
"link-id": "D1,1-3-1,D3,3-1-1",
"source": {
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"source-node": "D1",
"source-tp": "1-3-1"
},
"destination": {
"dest-node": "D3",
"dest-tp": "3-1-1"
},
"ietf-nrp:nrp": {
"partition-type": "virtual-sub-interface-partition",
"bandwidth-reservation": {
"bandwidth-value": "10000"
}
}
},
{
"link-id": "D3,3-1-1,D1,1-3-1",
"source": {
"source-node": "D3",
"source-tp": "3-1-1"
},
"destination": {
"dest-node": "D1",
"dest-tp": "1-3-1"
},
"ietf-nrp:nrp": {
"partition-type": "virtual-sub-interface-partition",
"bandwidth-reservation": {
"bandwidth-value": "10000"
}
}
},
{
"link-id": "D2,2-3-1,D3,3-2-1",
"source": {
"source-node": "D2",
"source-tp": "2-3-1"
},
"destination": {
"dest-node": "D3",
"dest-tp": "3-2-1"
},
"ietf-nrp:nrp": {
"partition-type": "virtual-sub-interface-partition",
"bandwidth-reservation": {
"bandwidth-value": "10000"
}
}
},
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{
"link-id": "D3,3-2-1,D2,2-3-1",
"source": {
"source-node": "D3",
"source-tp": "3-2-1"
},
"destination": {
"dest-node": "D2",
"dest-tp": "2-3-1"
},
"ietf-nrp:nrp": {
"partition-type": "virtual-sub-interface-partition",
"bandwidth-reservation": {
"bandwidth-value": "10000"
}
}
}
]
}
]
}
}
Figure 5: Instance data tree
Authors' Addresses
Bo Wu
Huawei Technologies
101 Software Avenue, Yuhua District
Nanjing
Jiangsu, 210012
China
Email: lana.wubo@huawei.com
Dhruv Dhody
Huawei Technologies
Divyashree Techno Park
Bangalore 560066
Karnataka
India
Email: dhruv.ietf@gmail.com
Wu, et al. Expires 12 January 2023 [Page 32]
Internet-Draft NRP YANG July 2022
Ying Cheng
China Unicom
Beijing
China
Email: chengying10@chinaunicom.cn
Wu, et al. Expires 12 January 2023 [Page 33]