MPLS Working Group T. Saad
Internet-Draft V. Beeram
Intended status: Standards Track Juniper Networks
Expires: May 6, 2021 November 2, 2020
YANG Data Model for Network Slice Per-Hop Definition
draft-bestbar-teas-yang-ns-phd-00
Abstract
This document defines a YANG data model for the management of Network
Slice Per-Hop Definitions (Slice-PHDs) on network slicing capable
nodes in IP/MPLS networks.
Requirements Language
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 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on May 6, 2021.
Copyright Notice
Copyright (c) 2020 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
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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 Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3
1.2. Tree Structure . . . . . . . . . . . . . . . . . . . . . 3
2. Network Slice Per-Hop Definition Model . . . . . . . . . . . 3
2.1. Model Usage . . . . . . . . . . . . . . . . . . . . . . . 3
2.2. Model Structure . . . . . . . . . . . . . . . . . . . . . 3
2.3. Network Slice Per-Hop-Behaviors . . . . . . . . . . . . . 4
2.4. Network Slices . . . . . . . . . . . . . . . . . . . . . 4
2.4.1. Slice Resource Reservation . . . . . . . . . . . . . 5
2.4.2. Slice Selectors . . . . . . . . . . . . . . . . . . . 5
2.4.3. Slice Per-Hop-Behavior . . . . . . . . . . . . . . . 6
2.4.4. Slice Membership . . . . . . . . . . . . . . . . . . 6
2.5. YANG Module . . . . . . . . . . . . . . . . . . . . . . . 7
3. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 25
4. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 25
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 25
6. Security Considerations . . . . . . . . . . . . . . . . . . . 26
7. References . . . . . . . . . . . . . . . . . . . . . . . . . 27
7.1. Normative References . . . . . . . . . . . . . . . . . . 27
7.2. Informative References . . . . . . . . . . . . . . . . . 28
Appendix A. Complete Model Tree Structure . . . . . . . . . . . 28
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 31
1. Introduction
Network slicing in IP/MPLS networks can be realized by partitioning
the shared network resources in just the control plane or in just the
data plane or in both the control and data planes
[I-D.bestbar-teas-ns-packet]. The latter two approaches require the
forwarding engine on each network slicing capable node to identify
the traffic belonging to a specific slice and to apply the
corresponding Slice Per-Hop Behavior (Slice-PHB) that determines the
forwarding treatment of the packets belonging to the network slice.
The identification of the slice that the packet belongs to and the
corresponding forwarding treatment that needs to be applied to the
packet is dictated by the Network Slice Per-Hop Definition (Slice-
PHD) that is provisioned on each network slicing capable node.
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This document defines a YANG data model for the provisioning and
management of Slice-PHDs on network slicing capable nodes in IP/MPLS
networks.
1.1. Terminology
The terminology for describing YANG data models is found in
[RFC7950].
The reader is expected to be familiar with the terminology specified
in [I-D.nsdt-teas-ietf-network-slice-definition],
[I-D.nsdt-teas-ns-framework] and [I-D.bestbar-teas-ns-packet]. The
term "Network Slice" used in this document must be interpreted as
"IETF Network Slice" [I-D.nsdt-teas-ietf-network-slice-definition].
1.2. Tree Structure
A simplified graphical representation of the data model is presented
in Appendix A of this document. The tree format defined in [RFC8340]
is used for the YANG data model tree representation.
2. Network Slice Per-Hop Definition Model
2.1. Model Usage
The instantiation of a network slice may require a network slice
controller that accepts a service layer slice customer intent as
input and translates it to a network-wide consistent per-hop slice
definition that is distributed to network slicing capable nodes. The
specification of the service layer slice customer intent is outside
the scope of this document. The data model defined in this document
covers the per-hop slice definition that is consumed by the network
slicing capable nodes.
2.2. Model Structure
The high-level model structure defined by this document is as shown
below:
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module: ietf-network-slice-phd
+--rw network-slicing!
+--rw network-slice-phbs
| +--rw network-slice-phb* [id]
| ............
+--rw network-slices
+--rw network-slice* [name]
| ............
+--rw slice-resource-reservation
| ............
+--rw slice-selectors
| +--rw slice-selector* [id]
| ............
+--rw slice-phb? ns-phb-ref
| ............
+--rw slice-membership
............
In addition to the set of Slice-PHDs (network-slices), the model also
includes a placeholder for the set of Slice-PHBs (network-slice-phbs)
that are referenced by the Slice-PHDs.
2.3. Network Slice Per-Hop-Behaviors
The Slice-PHBs (network-slice-phbs) container carries a list of
Slice-PHB (network-slice-phb) entries. Each of these entries can be
referenced by one or more Slice-PHD. A Slice-PHB entry can either
carry a reference to a generic PHB profile available on the node or
carry a custom PHB profile. The custom PHB profile includes
sufficient attributes to construct a slice specific Qos profile and
any classes within it.
+--rw network-slice-phbs
| +--rw network-slice-phb* [id]
| +--rw id uint16
| +--rw (profile-type)?
| +--:(profile)
| | +--rw profile? string
| +--:(custom-profile)
| ............
2.4. Network Slices
The Slice-PHDs are held in a container called 'network-slices'. Each
network-slice entry is identified by a name and holds the set of per-
hop attributes needed to instantiate the network slice. The four key
elements of each network-slice entry are discussed in the following
sub-sections.
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2.4.1. Slice Resource Reservation
The 'slice-resource-reservation' container carries data nodes that
are used to support Slice-aware Bandwidth Engineering. The data
nodes in this container facilitate preference-based preemption of
Slice-aware TE paths, sharing of resources amongst a group of slices
and backup slice path bandwidth protection.
+--rw slice-resource-reservation
| +--rw preference? uint16
| +--rw (max-bw-type)?
| | +--:(bw-value)
| | | +--rw maximum-bandwidth? uint64
| | +--:(bw-percentage)
| | +--rw maximum-bandwidth-percent?
| | rt-types:percentage
| +--rw shared-resource-groups* uint32
| +--rw protection
| +--rw backup-slice-id? uint32
| +--rw (backup-bw-type)?
| +--:(backup-bw-value)
| | +--rw backup-bandwidth? uint64
| +--:(backup-bw-percentage)
| +--rw backup-bandwidth-percent?
| rt-types:percentage
2.4.2. Slice Selectors
The 'slice-selectors' container carries a set of data plane field
selectors which are used to identify the packets belonging to the
given network slice. Each slice selector is uniquely identified by a
16-bit ID. The slice selector with the lowest ID is the default
slice selector used by all the topological elements that are members
of the given network slice. The other entries may be used when there
is a need to override the default slice selector on some select
topological elements.
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+--rw slice-selectors
| +--rw slice-selector* [id]
| +--rw id uint16
| +--rw mpls
| | +--rw (ss-mpls-type)?
| | +--:(label-value)
| | | +--rw label?
| | | | rt-types:mpls-label
| | | +--rw label-position? identityref
| | | +--rw label-position-offset? uint8
| | +--:(label-ranges)
| | +--rw label-range* [index]
| | +--rw index string
| | +--rw start-label?
| | | rt-types:mpls-label
| | +--rw end-label?
| | | rt-types:mpls-label
| | +--rw label-position?
| | | identityref
| | +--rw label-position-offset? uint8
| +--rw ipv4
| | +--rw destination-prefix* inet:ipv4-prefix
| +--rw ipv6
| | +--rw (ss-ipv6-type)?
| | +--:(ipv6-destination)
| | | +--rw destination-prefix*
| | | inet:ipv6-prefix
| | +--:(ipv6-flow-label)
| | +--rw slid-flow-labels
| | +--rw slid-flow-label* [slid]
| | +--rw slid inet:ipv6-flow-label
| | +--rw bitmask? uint32
| +--rw acl-ref* ns-acl-ref
2.4.3. Slice Per-Hop-Behavior
The Slice-PHB leaf carries a reference to the appropriate PHB that
needs to be applied for the given network slice. Unless specified
otherwise, this is the default Slice-PHB to be used by all the
topological elements that are members of the given network slice.
+--rw slice-phb? ns-phb-ref
2.4.4. Slice Membership
The 'slice-membership' container consists of a set of filtering
policies that are used to determine which topological elements on the
given node belong to the specific network slice. A filtering policy
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could either reference a predefined topology or specify the rules to
construct a customized topology using a set of include and exclude
filters. The topological elements that satisfy the network slice
membership criteria can optionally override the default Slice-PHB
and/or the default slice selector.
+--rw slice-membership
+--rw filter-policies
+--rw filter-policy* [id]
+--rw id
| uint16
+--rw (filter-type)?
| +--:(topology-ref)
| | +--rw (topo-ref-type)?
| | +--:(algo-id)
| | | +--rw algo-id? uint8
| | +--:(te-topo-id)
| | +--rw te-topology-identifier
| | +--rw provider-id? te-global-id
| | +--rw client-id? te-global-id
| | +--rw topology-id?
| | te-topology-id
| +--:(custom-topology)
| +--rw include
| | +--rw link-affinity* string
| | +--rw link-name* string
| | +--rw node-prefix* inet:ip-prefix
| | +--rw as* inet:as-number
| +--rw exclude
| +--rw link-affinity* string
| +--rw link-name* string
| +--rw node-prefix* inet:ip-prefix
| +--rw as* inet:as-number
+--rw slice-selector?
| ns-ss-ref
+--rw slice-phb?
ns-phb-ref
2.5. YANG Module
<CODE BEGINS> file "ietf-network-slice-phd@2020-11-02"
module ietf-network-slice-phd {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-network-slice-phd";
prefix "ns-phd";
import ietf-inet-types {
prefix "inet";
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reference
"RFC 6991: Common YANG Data Types";
}
import ietf-routing-types {
prefix "rt-types";
reference
"RFC 8294: Common YANG Data Types for the Routing Area";
}
import ietf-access-control-list {
prefix "acl";
reference
"RFC 8519: YANG Data Model for Network Access Control Lists
(ACLs)";
}
import ietf-te-types {
prefix te-types;
reference
"RFC 8776: Common YANG Data Types for Traffic Engineering";
}
organization
"IETF Traffic Engineering Architecture and Signaling (TEAS)
Working Group.";
contact
"WG Web: <http://tools.ietf.org/wg/teas/>
WG List: <mailto:teas@ietf.org>
Editor: Vishnu Pavan Beeram
<mailto:vbeeram@juniper.net>
Editor: Tarek Saad
<mailto:tsaad@juniper.net>";
description
"This YANG module defines a data model for managing Network
Slice Per-Hop Definitions (Slice-PHDs) on a network slicing
capable node.
Copyright (c) 2020 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 Simplified BSD License set
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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 "2020-11-02" {
description "Initial revision.";
reference
"RFC XXXX: YANG Data Model for Network Slice Per-Hop
Definitions (Slice-PHDs).";
}
/*
* I D E N T I T I E S
*/
/*
* Identity - MPLS Slice Selector Label Position Type
*/
identity ss-mpls-label-position-type {
description
"Base identity for the position of the MPLS label that is used
for slice selection.";
}
identity ss-mpls-label-position-top {
base ss-mpls-label-position-type;
description
"MPLS label that is used for slice selection is at the top of
the label stack.";
}
identity ss-mpls-label-position-bottom {
base ss-mpls-label-position-type;
description
"MPLS label that is used for slice selection is either at the
bottom or at a specific offset from the bottom of the label
stack.";
}
identity ss-mpls-label-position-indicator {
base ss-mpls-label-position-type;
description
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"MPLS label that is used for slice selection is immediately
preceded by a special purpose slice indicator label in the
label stack.";
}
/*
* Identity - Slice-PHB Class Direction
*/
identity s-phb-class-direction {
description
"Base identity for the direction of traffic to which the Slice
PHB class profile is applied.";
}
identity s-phb-class-direction-in {
base s-phb-class-direction;
description
"Slice PHB class profile is applied to incoming traffic.";
}
identity s-phb-class-direction-out {
base s-phb-class-direction;
description
"Slice PHB class profile is applied to outgoing traffic.";
}
identity s-phb-class-direction-in-out {
base s-phb-class-direction;
description
"Slice PHB class profile is applied to both incoming and
outgoing directions of traffic.";
}
/*
* Identity - Slice-PHB Class Priority
*/
identity s-phb-class-priority {
description
"Base identity for the priority of the child class scheduler.";
}
identity s-phb-class-priority-low {
base s-phb-class-drop-probability;
description
"Priority of the child class scheduler is low.";
}
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identity s-phb-class-priority-strict-high {
base s-phb-class-drop-probability;
description
"Priority of the child class scheduler is strict-high.";
}
/*
* Identity - Slice-PHB Class Drop Probability
*/
identity s-phb-class-drop-probability {
description
"Base identity for the drop probability applied to packets
exceeding the CIR of the class queue.";
}
identity s-phb-class-drop-probability-low {
base s-phb-class-drop-probability;
description
"Low drop probability applied to packets exceeding the CIR of
the class queue.";
}
identity s-phb-class-drop-probability-medium {
base s-phb-class-drop-probability;
description
"Medium drop probability applied to packets exceeding the CIR
of the class queue.";
}
identity s-phb-class-drop-probability-high {
base s-phb-class-drop-probability;
description
"High drop probability applied to packets exceeding the CIR of
the class queue.";
}
/*
* T Y P E D E F S
*/
typedef ns-acl-ref {
type leafref {
path "/acl:acls/acl:acl/acl:name";
}
description
"This type is used to reference an ACL.";
}
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typedef ns-ss-ref {
type leafref {
path "/network-slicing/network-slices/network-slice/"
+ "slice-selectors/slice-selector/id";
}
description
"This type is used to reference a Slice Selector (SS).";
}
typedef ns-phb-ref {
type leafref {
path "/network-slicing/network-slice-phbs/network-slice-phb/"
+ "id";
}
description
"This type is used to reference a Slice Per-Hop Behavior
(Slice-PHB).";
}
/*
* G R O U P I N G S
*/
/*
* Grouping - Slice Selector MPLS: Label location specific fields
*/
grouping ns-ss-mpls-label-location {
description
"Grouping for MPLS (SS) label location specific fields.";
leaf label-position {
type identityref {
base ss-mpls-label-position-type;
}
description
"MPLS label position - top, bottom with offset, Slice label
indicator.";
}
leaf label-position-offset {
when "derived-from-or-self(../label-position,"
+ "'ns-phd:ss-mpls-label-position-bottom')" {
description
"MPLS label position offset is relevant only when the
label-position is set to 'bottom'.";
}
type uint8;
description
"MPLS label position offset.";
}
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}
/*
* Grouping - Slice Selector (SS)
*/
grouping ns-slice-selector {
description
"Grouping for Slice Selectors.";
container slice-selectors {
description
"Container for Slice Selectors.";
list slice-selector {
key "id";
description
"List of Slice Selectors - this includes the default
selector and others used for overriding the default.";
leaf id {
type uint16;
description
"A 16-bit ID to uniquely identify the Slice Selector.
The Slice Selector with the lowest ID is the default
selector.";
}
container mpls {
description
"Container for MPLS Slice Selector.";
choice ss-mpls-type {
description
"Choices for MPLS Slice Selector.";
case label-value {
leaf label {
type rt-types:mpls-label;
description
"MPLS Slice Selector Label is explicitly
specified.";
}
uses ns-ss-mpls-label-location;
}
case label-ranges {
list label-range {
key "index";
unique "start-label end-label";
description
"MPLS Slice Selector Label is picked from a
specified set of label ranges.";
leaf index {
type string;
description
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"A string that uniquely identifies a label
range.";
}
leaf start-label {
type rt-types:mpls-label;
must '. <= ../end-label' {
error-message
"The start-label must be less than or equal "
+ "to end-label";
}
description
"Label-range start.";
}
leaf end-label {
type rt-types:mpls-label;
must '. >= ../start-label' {
error-message
"The end-label must be greater than or equal "
+ "to start-label";
}
description
"Label-range end.";
}
uses ns-ss-mpls-label-location;
}
}
}
}
container ipv4 {
description
"Container for IPv4 Slice Selector.";
leaf-list destination-prefix {
type inet:ipv4-prefix;
description
"IPv4 Slice Selector is picked from a specified set of
IPv4 destination prefixes.";
}
}
container ipv6 {
description
"Container for IPv6 Slice Selector.";
choice ss-ipv6-type {
description
"Choices for IPv6 Slice Selector.";
case ipv6-destination {
leaf-list destination-prefix {
type inet:ipv6-prefix;
description
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"IPv6 Slice Selector is picked from a specified
set of IPv6 destination prefixes.";
}
}
case ipv6-flow-label {
container slid-flow-labels {
description
"Container for a set of Slice IDs that are
encoded within the flow label.";
list slid-flow-label {
key "slid";
description
"IPv6 Slice Selector is picked from a set of
Slice IDs that are encoded within the flow
label.";
leaf slid {
type inet:ipv6-flow-label;
description
"Slice ID encoded inside the IPv6 flow label.";
}
leaf bitmask {
type uint32;
description
"Bitmask to extract the encoded Slice ID from
the IPv6 flow label.";
}
}
}
}
}
}
leaf-list acl-ref {
type ns-acl-ref;
description
"Slice Selection is done based on the specified list of
ACLs.";
}
}
}
}
/*
* Grouping - Slice Resource Reservation
*/
grouping ns-slice-resource-reservation {
description
"Grouping for Slice Resource Reservation.";
container slice-resource-reservation {
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description
"Container for Slice Resource Reservation.";
leaf preference {
type uint16;
description
"Slice control plane preference. A higher preference
indicates a more favorable slice resource
reservation than a lower preference.";
}
choice max-bw-type {
description
"Choice of maximum bandwidth specification.";
case bw-value {
leaf maximum-bandwidth {
type uint64;
description
"The maximum bandwidth allocated to a network slice on
the network resources - specified as absolute value.";
}
}
case bw-percentage {
leaf maximum-bandwidth-percent {
type rt-types:percentage;
description
"The maximum bandwidth allocated to a network slice on
the network resources - specified as percentage of
link capacity.";
}
}
}
leaf-list shared-resource-groups {
type uint32;
description
"List of shared resource groups that a network slice
shares its allocated resources with.";
}
container protection {
description
"Container for network slice protection reservation.";
leaf backup-slice-id {
type uint32;
description
"The Slice ID that identifies the network slice used
for backup paths that protect primary paths in a
specific network slice.";
}
choice backup-bw-type {
description
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"Choice of backup bandwidth specification.";
case backup-bw-value {
leaf backup-bandwidth {
type uint64;
description
"The maximum bandwidth on a network resource that
is allocated for backup traffic - specified as
absolute value.";
}
}
case backup-bw-percentage {
leaf backup-bandwidth-percent {
type rt-types:percentage;
description
"The maximum bandwidth on a network resource that
is allocated for backup traffic - specified as
percentage of the link capacity.";
}
}
}
}
}
}
/*
* Grouping - Slice-PHB
*/
grouping ns-slice-phb {
description
"Grouping for Slice-PHB.";
leaf slice-phb {
type ns-phb-ref;
description
"Reference to a specific Slice-PHB from the list global
Slice-PHBs.";
}
}
/*
* Grouping - Slice default profile override
*/
grouping ns-slice-default-profile-override {
description
"Grouping of fields that are used to override the default
profile of the network slice.";
leaf slice-selector {
type ns-ss-ref;
description
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"Reference to a specific Slice Selector.";
}
uses ns-slice-phb;
}
/*
* Grouping - Slice membership filter: Topology reference
*/
grouping ns-slice-membership-topo-ref {
description
"Grouping for topology reference slice membership filter.";
choice topo-ref-type {
description
"Choice of topology reference.";
case algo-id {
leaf algo-id {
type uint8;
description
"Algorithm ID.";
}
}
case te-topo-id {
uses te-types:te-topology-identifier;
}
}
}
/*
* Grouping - Slice membership filters: Custom topology
*/
grouping ns-slice-membership-custom-topo {
description
"Grouping for custom topology slice membership filters.";
leaf-list link-affinity {
type string;
description
"Match-filter is a list of link affinities.";
}
leaf-list link-name {
type string;
description
"Match-filter is a list of link names.";
}
leaf-list node-prefix {
type inet:ip-prefix;
description
"Match-filter is a list of node IDs.";
}
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leaf-list as {
type inet:as-number;
description
"Match-filter is a list of AS numbers.";
}
}
/*
* Grouping - Slice membership filters
*/
grouping ns-slice-membership-filters {
description
"Grouping for Slice Membership filters.";
choice filter-type {
description
"Choice of filter type.";
case topology-ref {
uses ns-slice-membership-topo-ref;
}
case custom-topology {
container include {
description
"Include policies.";
uses ns-slice-membership-custom-topo;
}
container exclude {
description
"Exclude policies.";
uses ns-slice-membership-custom-topo;
}
}
}
}
/*
* Grouping - Slice Membership
*/
grouping ns-slice-membership {
description
"Grouping for 'Slice Membership'.";
container slice-membership {
description
"Container for Slice Membership.";
container filter-policies {
description
"Container for topology filtering policies.";
list filter-policy {
key "id";
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description
"List of topology filtering policies.";
leaf id {
type uint16;
description
"A 16-bit ID that uniquely identifies the topology
filtering policy.";
}
uses ns-slice-membership-filters;
uses ns-slice-default-profile-override;
}
}
}
}
/*
* Grouping - Network Slice Per-Hop Behaviors (Slice-PHBs)
*/
grouping ns-phbs {
description
"Grouping for Slice-PHBs.";
container network-slice-phbs {
description
"Container for Slice-PHBs.";
list network-slice-phb {
key "id";
description
"List of Slice-PHBs.";
leaf id {
type uint16;
description
"A 16-bit ID that uniquely identifies the Slice-PHB.";
}
choice profile-type {
description
"Choice of PHB profile type.";
case profile {
description
"Generic PHB profile available on the network
element.";
leaf profile {
type string;
description
"Generic PHB profile identifier.";
}
}
case custom-profile {
description
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"Custom PHB profile.";
choice guaranteed-rate-type {
description
"Guaranteed rate is the committed information rate
(CIR) of the Slice. The guaranteed rate also
determines the amount of excess (extra) bandwidth
that a group of Slices can share. Extra bandwidth
is allocated among the group in proportion to the
guaranteed rate of each Slice.";
case rate {
leaf guaranteed-rate {
type uint64;
description
"Guaranteed rate specified as absolute value.";
}
}
case percentage {
leaf guaranteed-rate-percent {
type rt-types:percentage;
description
"Guaranteed rate specified in percentage.";
}
}
}
choice shaping-rate-type {
description
"Shaping rate is the maximum bandwidth of the slice,
or the peak information rate (PIR) of a Slice.";
case rate {
leaf shaping-rate {
type uint64;
description
"Shaping rate specified as absolute value.";
}
}
case percentage {
leaf shaping-rate-percent {
type rt-types:percentage;
description
"Shaping rate specified in percentage.";
}
}
}
container classes {
description
"Container for classes.";
list class {
key class-id;
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description
"List of classes.";
leaf class-id {
type string;
description
"A string to uniquely identify a class.";
}
leaf direction {
type identityref {
base s-phb-class-direction;
}
description
"Class direction.";
}
leaf priority {
type identityref {
base s-phb-class-priority;
}
description
"Priority of the class scheduler. Only one Slice
class queue can be set as a strict-high priority
queue. Strict-high priority allocates the
scheduled bandwidth to the queue before any
other queue receives bandwidth. Other queues
receive the bandwidth that remains after the
strict-high queue has been serviced.";
}
choice guaranteed-rate-type {
description
"Guaranteed Rate is the Committed information
rate (CIR) of Slice class - specified as
absolute value or percentage.";
case rate {
leaf guaranteed-rate {
type uint64;
description
"Guaranteed rate specified as absolute
value.";
}
}
case percentage {
leaf guaranteed-rate-percent {
type rt-types:percentage;
description
"Guaranteed rate specified in percentage.";
}
}
}
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leaf drop-probability {
type identityref {
base s-phb-class-drop-probability;
}
description
"Drop probability applied to packets exceeding
the CIR of the class queue.";
}
choice maximum-bandwidth-type {
description
"Maximum bandwidth is the Peak information
rate (PIR) of Slice class - specified as
absolute value or percentage.";
case rate {
leaf maximum-bandwidth {
type uint64;
description
"Maximum bandwidth specified as absolute
value.";
}
}
case percentage {
leaf maximum-bandwidth-percent {
type rt-types:percentage;
description
"Maximum bandwidth specified as percentage.";
}
}
}
choice delay-buffer-size-type {
description
"Size of the queue buffer as a percentage of the
dedicated buffer space - specified as value or
percentage.";
case value {
leaf delay-buffer-size {
type uint64;
description
"Delay buffer size.";
}
}
case percentage {
leaf delay-buffer-size-percent {
type rt-types:percentage;
description
"Delay buffer size specified as percentage.";
}
}
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}
}
}
}
}
}
}
}
/*
* Grouping - Network Slice Per-Hop Definitions (Slice-PHDs)
*/
grouping ns-entries {
description
"Grouping for Slice-PHDs.";
container network-slices {
description
"Container for Slice-PHD entries (network-slices).";
list network-slice {
key "name";
unique "id";
description
"List of network slices.";
leaf name {
type string;
description
"A string that uniquely identifies the network slice.";
}
leaf id {
type uint32;
description
"A 32-bit ID that uniquely identifies the network
slice.";
}
uses ns-slice-resource-reservation;
uses ns-slice-selector;
uses ns-slice-phb;
uses ns-slice-membership;
}
}
}
/*
* Top-level container - Network Slicing
*/
container network-slicing {
presence "Enable network slicing.";
description
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"Top-level container for network slicing specific constructs
on a network slicing capable node.";
uses ns-phbs;
uses ns-entries;
}
}
<CODE ENDS>
3. Acknowledgements
The authors would like to thank Krzysztof Szarkowicz for his input
from discussions.
4. Contributors
The following individuals contributed to this document:
Colby Barth
Juniper Networks
Email: cbarth@juniper.net
Srihari R. Sangli
Juniper Networks
Email: ssangli@juniper.net
Chandra Ramachandran
Juniper Networks
Email: csekar@juniper.net
5. IANA Considerations
This document registers the following 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-network-slice-phd
Registrant Contact: The TEAS WG of the IETF.
XML: N/A, the requested URI is an XML namespace.
This document registers a YANG module in the YANG Module Names
registry [RFC6020].
name: ietf-network-slice-phd
namespace: urn:ietf:params:xml:ns:yang:ietf-network-slice-phd
prefix: ns-phd
reference: RFCXXXX
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6. 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 Network Configuration Access Control Model (NACM) [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.
The data nodes defined in this YANG module that are
writable/creatable/deletable (i.e., config true, which is the
default) 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. These are the subtrees and data nodes and their
sensitivity/vulnerability:
* "/network-slicing/network-slice-phbs": This subtree specifies the
configurations for network slice per-hop behaviors. By
manipulating these data nodes, a malicious attacker may cause
unauthorized and improper behavior to be provided for the slice
traffic on the network element.
* "/network-slicing/network-slices": This subtree specifies the
configurations for network slices on a given network element. By
manipulating these data nodes, a malicious attacker may cause
unauthorized and improper behavior to be provided for the slice
traffic on the network element.
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. These are the subtrees and data
nodes and their sensitivity/vulnerability:
* "/network-slicing/network-slice-phbs": Unauthorized access to this
subtree can disclose the network slice PHBs defined on the network
element.
* "/network-slicing/network-slices": Unauthorized access to this
subtree can disclose the network slice definitions on the network
element.
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7. References
7.1. Normative References
[I-D.bestbar-teas-ns-packet]
Saad, T. and V. Beeram, "Realizing Network Slices in IP/
MPLS Networks", draft-bestbar-teas-ns-packet-00 (work in
progress), October 2020.
[I-D.nsdt-teas-ietf-network-slice-definition]
Rokui, R., Homma, S., Makhijani, K., Contreras, L., and J.
Tantsura, "Definition of IETF Network Slices", draft-nsdt-
teas-ietf-network-slice-definition-00 (work in progress),
October 2020.
[I-D.nsdt-teas-ns-framework]
Gray, E. and J. Drake, "Framework for Transport Network
Slices", draft-nsdt-teas-ns-framework-04 (work in
progress), July 2020.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[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>.
[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>.
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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>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[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>.
[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>.
7.2. Informative References
[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>.
Appendix A. Complete Model Tree Structure
module: ietf-network-slice-phd
+--rw network-slicing!
+--rw network-slice-phbs
| +--rw network-slice-phb* [id]
| +--rw id uint16
| +--rw (profile-type)?
| +--:(profile)
| | +--rw profile? string
| +--:(custom-profile)
| +--rw (guaranteed-rate-type)?
| | +--:(rate)
| | | +--rw guaranteed-rate? uint64
| | +--:(percentage)
| | +--rw guaranteed-rate-percent?
| | rt-types:percentage
| +--rw (shaping-rate-type)?
| | +--:(rate)
| | | +--rw shaping-rate? uint64
| | +--:(percentage)
| | +--rw shaping-rate-percent?
| | rt-types:percentage
| +--rw classes
| +--rw class* [class-id]
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| +--rw class-id
| | string
| +--rw direction?
| | identityref
| +--rw priority?
| | identityref
| +--rw (guaranteed-rate-type)?
| | +--:(rate)
| | | +--rw guaranteed-rate?
| | | uint64
| | +--:(percentage)
| | +--rw guaranteed-rate-percent?
| | rt-types:percentage
| +--rw drop-probability?
| | identityref
| +--rw (maximum-bandwidth-type)?
| | +--:(rate)
| | | +--rw maximum-bandwidth?
| | | uint64
| | +--:(percentage)
| | +--rw maximum-bandwidth-percent?
| | rt-types:percentage
| +--rw (delay-buffer-size-type)?
| +--:(value)
| | +--rw delay-buffer-size?
| | uint64
| +--:(percentage)
| +--rw delay-buffer-size-percent?
| rt-types:percentage
+--rw network-slices
+--rw network-slice* [name]
+--rw name string
+--rw id? uint32
+--rw slice-resource-reservation
| +--rw preference? uint16
| +--rw (max-bw-type)?
| | +--:(bw-value)
| | | +--rw maximum-bandwidth? uint64
| | +--:(bw-percentage)
| | +--rw maximum-bandwidth-percent?
| | rt-types:percentage
| +--rw shared-resource-groups* uint32
| +--rw protection
| +--rw backup-slice-id? uint32
| +--rw (backup-bw-type)?
| +--:(backup-bw-value)
| | +--rw backup-bandwidth? uint64
| +--:(backup-bw-percentage)
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| +--rw backup-bandwidth-percent?
| rt-types:percentage
+--rw slice-selectors
| +--rw slice-selector* [id]
| +--rw id uint16
| +--rw mpls
| | +--rw (ss-mpls-type)?
| | +--:(label-value)
| | | +--rw label?
| | | | rt-types:mpls-label
| | | +--rw label-position? identityref
| | | +--rw label-position-offset? uint8
| | +--:(label-ranges)
| | +--rw label-range* [index]
| | +--rw index string
| | +--rw start-label?
| | | rt-types:mpls-label
| | +--rw end-label?
| | | rt-types:mpls-label
| | +--rw label-position?
| | | identityref
| | +--rw label-position-offset? uint8
| +--rw ipv4
| | +--rw destination-prefix* inet:ipv4-prefix
| +--rw ipv6
| | +--rw (ss-ipv6-type)?
| | +--:(ipv6-destination)
| | | +--rw destination-prefix*
| | | inet:ipv6-prefix
| | +--:(ipv6-flow-label)
| | +--rw slid-flow-labels
| | +--rw slid-flow-label* [slid]
| | +--rw slid inet:ipv6-flow-label
| | +--rw bitmask? uint32
| +--rw acl-ref* ns-acl-ref
+--rw slice-phb? ns-phb-ref
+--rw slice-membership
+--rw filter-policies
+--rw filter-policy* [id]
+--rw id
| uint16
+--rw (filter-type)?
| +--:(topology-ref)
| | +--rw (topo-ref-type)?
| | +--:(algo-id)
| | | +--rw algo-id? uint8
| | +--:(te-topo-id)
| | +--rw te-topology-identifier
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| | +--rw provider-id? te-global-id
| | +--rw client-id? te-global-id
| | +--rw topology-id?
| | te-topology-id
| +--:(custom-topology)
| +--rw include
| | +--rw link-affinity* string
| | +--rw link-name* string
| | +--rw node-prefix* inet:ip-prefix
| | +--rw as* inet:as-number
| +--rw exclude
| +--rw link-affinity* string
| +--rw link-name* string
| +--rw node-prefix* inet:ip-prefix
| +--rw as* inet:as-number
+--rw slice-selector?
| ns-ss-ref
+--rw slice-phb?
ns-phb-ref
Authors' Addresses
Tarek Saad
Juniper Networks
Email: tsaad@juniper.net
Vishnu Pavan Beeram
Juniper Networks
Email: vbeeram@juniper.net
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