draft-ietf-teas-ietf-network-slices-01.txt   draft-ietf-teas-ietf-network-slices-02.txt 
Network Working Group A. Farrel, Ed. Network Working Group A. Farrel, Ed.
Internet-Draft Old Dog Consulting Internet-Draft Old Dog Consulting
Intended status: Informational E. Gray Intended status: Informational E. Gray
Expires: October 18, 2021 Ericsson Expires: November 5, 2021 Independent
J. Drake J. Drake
Juniper Networks Juniper Networks
R. Rokui R. Rokui
Nokia Nokia
S. Homma S. Homma
NTT NTT
K. Makhijani K. Makhijani
Futurewei Futurewei
LM. Contreras LM. Contreras
Telefonica Telefonica
J. Tantsura J. Tantsura
Juniper Networks Juniper Networks
April 16, 2021 May 4, 2021
Framework for IETF Network Slices Framework for IETF Network Slices
draft-ietf-teas-ietf-network-slices-01 draft-ietf-teas-ietf-network-slices-02
Abstract Abstract
This document describes network slicing in the context of networks This document describes network slicing in the context of networks
built from IETF technologies. It defines the term "IETF Network built from IETF technologies. It defines the term "IETF Network
Slice" and establishes the general principles of network slicing in Slice" and establishes the general principles of network slicing in
the IETF context. the IETF context.
The document discusses the general framework for requesting and The document discusses the general framework for requesting and
operating IETF Network Slices, the characteristics of an IETF Network operating IETF Network Slices, the characteristics of an IETF Network
skipping to change at page 2, line 12 skipping to change at page 2, line 12
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/. Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on October 18, 2021. This Internet-Draft will expire on November 5, 2021.
Copyright Notice Copyright Notice
Copyright (c) 2021 IETF Trust and the persons identified as the Copyright (c) 2021 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents Provisions Relating to IETF Documents
(https://trustee.ietf.org/license-info) in effect on the date of (https://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents publication of this document. Please review these documents
skipping to change at page 2, line 39 skipping to change at page 2, line 39
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Background . . . . . . . . . . . . . . . . . . . . . . . 4 1.1. Background . . . . . . . . . . . . . . . . . . . . . . . 4
2. Terms and Abbreviations . . . . . . . . . . . . . . . . . . . 5 2. Terms and Abbreviations . . . . . . . . . . . . . . . . . . . 5
3. IETF Network Slice Objectives . . . . . . . . . . . . . . . . 6 3. IETF Network Slice Objectives . . . . . . . . . . . . . . . . 6
3.1. Definition and Scope of IETF Network Slice . . . . . . . 6 3.1. Definition and Scope of IETF Network Slice . . . . . . . 6
4. IETF Network Slice System Characteristics . . . . . . . . . . 7 4. IETF Network Slice System Characteristics . . . . . . . . . . 7
4.1. Objectives for IETF Network Slices . . . . . . . . . . . 7 4.1. Objectives for IETF Network Slices . . . . . . . . . . . 7
4.1.1. Service Level Objectives . . . . . . . . . . . . . . 8 4.1.1. Service Level Objectives . . . . . . . . . . . . . . 8
4.2. IETF Network Slice Endpoints . . . . . . . . . . . . . . 10 4.1.2. Service Level Expectations . . . . . . . . . . . . . 9
4.2.1. IETF Network Slice Connectivity Types . . . . . . . . 12 4.2. IETF Network Slice Endpoints . . . . . . . . . . . . . . 12
4.3. IETF Network Slice Decomposition . . . . . . . . . . . . 12 4.2.1. IETF Network Slice Connectivity Types . . . . . . . . 13
5. Framework . . . . . . . . . . . . . . . . . . . . . . . . . . 12 4.3. IETF Network Slice Decomposition . . . . . . . . . . . . 13
5.1. IETF Network Slice Stakeholders . . . . . . . . . . . . . 12 5. Framework . . . . . . . . . . . . . . . . . . . . . . . . . . 14
5.2. Expressing Connectivity Intents . . . . . . . . . . . . . 13 5.1. IETF Network Slice Stakeholders . . . . . . . . . . . . . 14
5.3. IETF Network Slice Controller (NSC) . . . . . . . . . . . 15 5.2. Expressing Connectivity Intents . . . . . . . . . . . . . 15
5.3.1. IETF Network Slice Controller Interfaces . . . . . . 17 5.3. IETF Network Slice Controller (NSC) . . . . . . . . . . . 17
5.3.2. Northbound Interface (NBI) . . . . . . . . . . . . . 17 5.3.1. IETF Network Slice Controller Interfaces . . . . . . 18
5.4. IETF Network Slice Structure . . . . . . . . . . . . . . 18 5.3.2. Northbound Interface (NBI) . . . . . . . . . . . . . 19
5.5. Realizing IETF Network Slice . . . . . . . . . . . . . . 20 5.4. IETF Network Slice Structure . . . . . . . . . . . . . . 20
5.5.1. Underlying Technology . . . . . . . . . . . . . . . . 20 6. Realizing IETF Network Slices . . . . . . . . . . . . . . . . 21
6. Applicability of ACTN to IETF Network Slices . . . . . . . . 21 6.1. Procedures to Realize IETF Network Slices . . . . . . . . 21
6.2. Applicability of ACTN to IETF Network Slices . . . . . . 22
6.3. Applicability of Enhanced VPNs to IETF Network Slices . . 22
6.4. Network Slicing and Slice Aggregation in IP/MPLS Networks 23
7. Isolation in IETF Network Slices . . . . . . . . . . . . . . 23 7. Isolation in IETF Network Slices . . . . . . . . . . . . . . 23
7.1. Isolation as a Service Requirement . . . . . . . . . . . 23 7.1. Isolation as a Service Requirement . . . . . . . . . . . 23
7.2. Isolation in IETF Network Slice Realization . . . . . . . 24 7.2. Isolation in IETF Network Slice Realization . . . . . . . 24
8. Management Considerations . . . . . . . . . . . . . . . . . . 24 8. Management Considerations . . . . . . . . . . . . . . . . . . 24
9. Security Considerations . . . . . . . . . . . . . . . . . . . 24 9. Security Considerations . . . . . . . . . . . . . . . . . . . 24
9.1. Privacy Considerations . . . . . . . . . . . . . . . . . 25 10. Privacy Considerations . . . . . . . . . . . . . . . . . . . 25
10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 26 11. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 26
11. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 26 12. Informative References . . . . . . . . . . . . . . . . . . . 26
12. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 26 Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 30
13. References . . . . . . . . . . . . . . . . . . . . . . . . . 27 Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . 30
13.1. Normative References . . . . . . . . . . . . . . . . . . 27 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 31
13.2. Informative References . . . . . . . . . . . . . . . . . 27
Appendix A. Unused Material . . . . . . . . . . . . . . . . . . 31
A.1. Abstract . . . . . . . . . . . . . . . . . . . . . . . . 32
A.2. Management Systems or Other Applications . . . . . . . . 32
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 32
1. Introduction 1. Introduction
===================== EDITOR'S NOTE =====================
This document is a merge of the text in
[I-D.ietf-teas-ietf-network-slice-definition] and
[I-D.ietf-teas-ietf-network-slice-framework]. In this version, the
text included from the contributing documents has been re-arranged to
rationalise the structure, but no substantive changes have been made.
Additionally, the Editor has made a number of stylistic edits and
fixed further simple editorial and formatting issues.
In the case that the source text is not used within the document, it
is presented in Appendix A.
=================== END EDITOR'S NOTE ===================
A number of use cases benefit from network connections that along A number of use cases benefit from network connections that along
with the connectivity provide assurance of meeting a specific set of with the connectivity provide assurance of meeting a specific set of
objectives with respect to network resources use. This connectivity objectives with respect to network resources use. This connectivity
and resource commitment is referred to as a network slice. Since the and resource commitment is referred to as a network slice. Since the
term network slice is rather generic, the qualifying term "IETF" is term network slice is rather generic, the qualifying term "IETF" is
used in this document to limit the scope of network slice to network used in this document to limit the scope of network slice to network
technologies described and standardized by the IETF. This document technologies described and standardized by the IETF. This document
defines the concept of IETF Network Slices that provide connectivity defines the concept of IETF Network Slices that provide connectivity
coupled with a set of specific commitments of network resources coupled with a set of specific commitments of network resources
between a number of endpoints over a shared network infrastructure. between a number of endpoints over a shared network infrastructure.
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o Network infrastructure sharing among operators o Network infrastructure sharing among operators
o NFV connectivity and Data Center Interconnect o NFV connectivity and Data Center Interconnect
IETF Network Slices are created and managed within the scope of one IETF Network Slices are created and managed within the scope of one
or more network technologies (e.g., IP, MPLS, optical). They are or more network technologies (e.g., IP, MPLS, optical). They are
intended to enable a diverse set of applications that have different intended to enable a diverse set of applications that have different
requirements to coexist on the shared network infrastructure. A requirements to coexist on the shared network infrastructure. A
request for an IETF Network Slice is technology-agnostic so as to request for an IETF Network Slice is technology-agnostic so as to
allow a consumer to describe their network connectivity objectives in allow a customer to describe their network connectivity objectives in
a common format, independent of the underlying technologies used. a common format, independent of the underlying technologies used.
This document also provides a framework for discussing IETF Network This document also provides a framework for discussing IETF Network
Slices. This framework is intended as a structure for discussing Slices. This framework is intended as a structure for discussing
interfaces and technologies. It is not intended to specify a new set interfaces and technologies. It is not intended to specify a new set
of concrete interfaces or technologies. Rather, the idea is that of concrete interfaces or technologies. Rather, the idea is that
existing or under-development IETF technologies (plural) can be used existing or under-development IETF technologies (plural) can be used
to realize the concepts expressed herein. to realize the concepts expressed herein.
For example, virtual private networks (VPNs) have served the industry For example, virtual private networks (VPNs) have served the industry
well as a means of providing different groups of users with logically well as a means of providing different groups of users with logically
isolated access to a common network. The common or base network that isolated access to a common network. The common or base network that
is used to provide the VPNs is often referred to as an underlay is used to support the VPNs is often referred to as an underlay
network, and the VPN is often called an overlay network. As an network, and the VPN is often called an overlay network. An overlay
example technology, a VPN may in turn serve as an underlay network network may, in turn, serve as an underlay network to support another
for IETF Network Slices. overlay network.
Note that it is conceivable that extensions to these IETF Note that it is conceivable that extensions to these IETF
technologies are needed in order to fully support all the ideas that technologies are needed in order to fully support all the ideas that
can be implemented with slices, but at least in the beginning there can be implemented with slices. Evaluation of existing technologies,
is no plan for the creation of new protocols or interfaces. proposed extensions to existing protocols and interfaces, and the
creation of new protocols or interfaces is outside the scope of this
document.
1.1. Background 1.1. Background
Driven largely by needs surfacing from 5G, the concept of network Driven largely by needs surfacing from 5G, the concept of network
slicing has gained traction ([NGMN-NS-Concept], [TS23501], [TS28530], slicing has gained traction ([NGMN-NS-Concept], [TS23501], [TS28530],
and [BBF-SD406]). In [TS23501], a Network Slice is defined as "a and [BBF-SD406]). In [TS23501], a Network Slice is defined as "a
logical network that provides specific network capabilities and logical network that provides specific network capabilities and
network characteristics", and a Network Slice Instance is defined as network characteristics", and a Network Slice Instance is defined as
"A set of Network Function instances and the required resources (e.g. "A set of Network Function instances and the required resources (e.g.
compute, storage and networking resources) which form a deployed compute, storage and networking resources) which form a deployed
Network Slice." According to [TS28530], an end-to-end network slice Network Slice." According to [TS28530], an end-to-end network slice
consists of three major types of network segments: Radio Access consists of three major types of network segments: Radio Access
Network (RAN), Transport Network (TN) and Core Network (CN). IETF Network (RAN), Transport Network (TN) and Core Network (CN). An IETF
Network Slice provides the required connectivity between different Network Slice provides the required connectivity between different
entities in RAN and CN segments of an end-to-end network slice, with entities in RAN and CN segments of an end-to-end network slice, with
a specific performance commitment. For each end-to-end network a specific performance commitment. For each end-to-end network
slice, the topology and performance requirement on a consumer's use slice, the topology and performance requirement on a customer's use
of IETF Network Slice can be very different, which requires the of IETF Network Slice can be very different, which requires the
underlay network to have the capability of supporting multiple underlay network to have the capability of supporting multiple
different IETF Network Slices. different IETF Network Slices.
While network slices are commonly discussed in the context of 5G, it While network slices are commonly discussed in the context of 5G, it
is important to note that IETF Network Slices are a narrower concept, is important to note that IETF Network Slices are a narrower concept,
and focus primarily on particular network connectivity aspects. and focus primarily on particular network connectivity aspects.
Other systems, including 5G deployments, may use IETF Network Slices Other systems, including 5G deployments, may use IETF Network Slices
as a component to create entire systems and concatenated constructs as a component to create entire systems and concatenated constructs
that match their needs, including end-to-end connectivity. that match their needs, including end-to-end connectivity.
A IETF Network Slice could span multiple technologies and multiple A IETF Network Slice could span multiple technologies and multiple
administrative domains. Depending on the IETF Network Slice administrative domains. Depending on the IETF Network Slice
consumer's requirements, an IETF Network Slice could be isolated from customer's requirements, an IETF Network Slice could be isolated from
other, often concurrent IETF Network Slices in terms of data, control other, often concurrent IETF Network Slices in terms of data, control
and management planes. and management planes.
The consumer expresses requirements for a particular IETF Network The customer expresses requirements for a particular IETF Network
Slice by specifying what is required rather than how the requirement Slice by specifying what is required rather than how the requirement
is to be fulfilled. That is, the IETF Network Slice consumer's view is to be fulfilled. That is, the IETF Network Slice customer's view
of an IETF Network Slice is an abstract one. of an IETF Network Slice is an abstract one.
Thus, there is a need to create logical network structures with Thus, there is a need to create logical network structures with
required characteristics. The consumer of such a logical network can required characteristics. The customer of such a logical network can
require a degree of isolation and performance that previously might require a degree of isolation and performance that previously might
not have been satisfied by traditional overlay VPNs. Additionally, not have been satisfied by traditional overlay VPNs. Additionally,
the IETF Network Slice consumer might ask for some level of control the IETF Network Slice customer might ask for some level of control
of their virtual networks, e.g., to customize the service paths in a of their virtual networks, e.g., to customize the service paths in a
network slice. network slice.
This document specifies a framework for the use of existing This document specifies definitions and a framework for the provision
technologies as components to provide an IETF Network Slice service, of an IETF Network Slice service. Section 6 briefly indicates some
and might also discuss (or reference) modified and potential new candidate technologies for realizing IETF Network Slices.
technologies, as they develop (such as candidate technologies
described in section 5 of [I-D.ietf-teas-enhanced-vpn]).
2. Terms and Abbreviations 2. Terms and Abbreviations
The terms and abbreviations used in this document are listed below. The terms and abbreviations used in this document are listed below.
o NBI: NorthBound Interface o NBI: NorthBound Interface
o NS: Network Slice
o NSC: Network Slice Controller o NSC: Network Slice Controller
o NSE: Network Slice Endpoint o NSE: Network Slice Endpoint
o SBI: SouthBound Interface o SBI: SouthBound Interface
o SLA: Service Level Agreement o SLA: Service Level Agreement
o SLI: Service Level Indicator o SLI: Service Level Indicator
o SLO: Service Level Objective o SLO: Service Level Objective
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used to specify network-related conditions for particular traffic used to specify network-related conditions for particular traffic
flows. flows.
It is also intended that, once created, these slices can be It is also intended that, once created, these slices can be
monitored, modified, deleted, and otherwise managed. monitored, modified, deleted, and otherwise managed.
It is also intended that applications and components will be able to It is also intended that applications and components will be able to
use these IETF Network Slices to move packets between the specified use these IETF Network Slices to move packets between the specified
end-points in accordance with specified characteristics. end-points in accordance with specified characteristics.
As an example of requirements that might apply to IETF Network
Slices, see [I-D.ietf-teas-enhanced-vpn] (in particular, section 3).
3.1. Definition and Scope of IETF Network Slice 3.1. Definition and Scope of IETF Network Slice
The definition of a network slice in IETF context is as follows: The definition of a network slice in IETF context is as follows:
An IETF Network Slice is a logical network topology connecting a An IETF Network Slice is a logical network topology connecting a
number of endpoints using a set of shared or dedicated network number of endpoints using a set of shared or dedicated network
resources that are used to satisfy specific Service Level Objectives resources that are used to satisfy specific Service Level Objectives
(SLOs). (SLOs).
An IETF Network Slice combines the connectivity resource requirements An IETF Network Slice combines the connectivity resource requirements
and associated network behaviors such as bandwidth, latency, jitter, and associated network behaviors such as bandwidth, latency, jitter,
and network functions with other resource behaviors such as compute and network functions with other resource behaviors such as compute
and storage availability. IETF Network Slices are independent of the and storage availability. IETF Network Slices are independent of the
underlying infrastructure connectivity and technologies used. This underlying infrastructure connectivity and technologies used. This
is to allow an IETF Network Slice consumer to describe their network is to allow an IETF Network Slice customer to describe their network
connectivity and relevant objectives in a common format, independent connectivity and relevant objectives in a common format, independent
of the underlying technologies used. of the underlying technologies used.
IETF Network Slices may be combined hierarchically, so that a network IETF Network Slices may be combined hierarchically, so that a network
slice may itself be sliced. They may also be combined sequentially slice may itself be sliced. They may also be combined sequentially
so that various different networks can each be sliced and the network so that various different networks can each be sliced and the network
slices placed into a sequence to provide an end-to-end service. This slices placed into a sequence to provide an end-to-end service. This
form of sequential combination is utilized in some services such as form of sequential combination is utilized in some services such as
in 3GPP's 5G network [TS23501]. in 3GPP's 5G network [TS23501].
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signaling or via controller(s) and fulfilling all or some of SLOs to signaling or via controller(s) and fulfilling all or some of SLOs to
all of the traffic in the slice or to specific flows. all of the traffic in the slice or to specific flows.
4. IETF Network Slice System Characteristics 4. IETF Network Slice System Characteristics
The following subsections describe the characteristics of IETF The following subsections describe the characteristics of IETF
Network Slices. Network Slices.
4.1. Objectives for IETF Network Slices 4.1. Objectives for IETF Network Slices
An IETF Network Slice is defined in terms of several quantifiable An IETF Network Slice service is defined in terms of quantifiable
characteristics or Service Level Objectives (SLOs). SLOs along with characteristics known as Service Level Objectives (SLOs) and
the terms Service Level Indicator (SLI) and Service Level Agreement unquantifiable characteristics known as Service Level Expectations
(SLA) are used to define the performance of a service at different (SLEs). SLOs are expressed in terms Service Level Indicators (SLIs),
levels. and together with the SLEs form the contractual agreement between
service customer and service provider known as a Service Level
Agreement (SLA).
A Service Level Indicator (SLI) is a quantifiable measure of an The terms are defined as follows:
aspect of the performance of a network. For example, it may be a
measure of throughput in bits per second, or it may be a measure of
latency in milliseconds.
A Service Level Objective (SLO) is a target value or range for the o A Service Level Indicator (SLI) is a quantifiable measure of an
measurements returned by observation of an SLI. For example, an SLO aspect of the performance of a network. For example, it may be a
may be expressed as "SLI <= target", or "lower bound <= SLI <= upper measure of throughput in bits per second, or it may be a measure
bound". A network slice is expressed in terms of the set of SLOs of latency in milliseconds.
that are to be delivered for the different connections between
endpoints.
A Service Level Agreement (SLA) is an explicit or implicit contract o A Service Level Objective (SLO) is a target value or range for the
between the consumer of an IETF Network Slice and the provider of the measurements returned by observation of an SLI. For example, an
slice. The SLA is expressed in terms of a set of SLOs and may SLO may be expressed as "SLI <= target", or "lower bound <= SLI <=
include commercial terms as well as the consequences of missing/ upper bound". A customer can determine whether the provider is
violating the SLOs they contain. meeting the SLOs by performing measurements on the traffic.
Additional descriptions of IETF Network Slice attributes is covered o A Service Level Expectation (SLE) is an expression of an
in [I-D.contreras-teas-slice-nbi]. unmeasurable service-related request that a customer of an IETF
network slice makes of the provider. An SLE is distinct from an
SLO because the customer may have little or no way of determining
whether the SLE is being met, but they still contract with the
provider for a service that meets the expectation.
o A Service Level Agreement (SLA) is an explicit or implicit
contract between the customer of an IETF Network Slice and the
provider of the slice. The SLA is expressed in terms of a set of
SLOs and SLEs that are to be applied to the connections between
the service endpoints, and may include commercial terms as well as
the consequences of missing/violating the SLOs they contain.
4.1.1. Service Level Objectives 4.1.1. Service Level Objectives
SLOs define a set of network attributes and characteristics that SLOs define a set of network attributes and characteristics that
describe an IETF Network Slice. SLOs do not describe how the IETF describe an IETF Network Slice. SLOs do not describe how the IETF
Network Slices are implemented or realized in the underlying network Network Slices are implemented or realized in the underlying network
layers. Instead, they are defined in terms of dimensions of layers. Instead, they are defined in terms of dimensions of
operation (time, capacity, etc.), availability, and other attributes. operation (time, capacity, etc.), availability, and other attributes.
An IETF Network Slice can have one or more SLOs associated with it. An IETF Network Slice can have one or more SLOs associated with it.
The SLOs are combined in an SLA. The SLOs are defined for sets of The SLOs are combined in an SLA. The SLOs are defined for sets of
two or more endpoints and apply to specific directions of traffic two or more endpoints and apply to specific directions of traffic
flow. That is, they apply to specific source endpoints and specific flow. That is, they apply to specific source endpoints and specific
connections between endpoints within the set of endpoints and connections between endpoints within the set of endpoints and
connections in the IETF Network Slice. connections in the IETF Network Slice.
4.1.1.1. Minimal Set of SLOs SLOs define a set of measurable network attributes and
characteristics that describe an IETF Network Slice service. SLOs do
not describe how the IETF network slices are implemented or realized
in the underlying network layers. Instead, they are defined in terms
of dimensions of operation (time, capacity, etc.), availability, and
other attributes. An IETF Network Slice service can have one or more
SLOs associated with it. The SLOs are combined with Service Level
Expectations in an SLA.
This document defines a minimal set of SLOs and later systems or An IETF network slice service may include multiple connection
standards could extend this set as described in Section 4.1.1.2. constructs that associate sets of endpoints. SLOs apply to sets of
two or more endpoints and apply to specific directions of traffic
flow. That is, they apply to a specific source endpoint and the
connection to specific destination endpoints.
SLOs can be categorized in to 'Directly Measurable Objectives' or 4.1.1.1. Some Common SLOs
'Indirectly Measurable Objectives'. Objectives such as guaranteed
minimum bandwidth, guaranteed maximum latency, maximum permissible
delay variation, maximum permissible packet loss rate, and
availability are 'Directly Measurable Objectives'. While 'Indirectly
Measurable Objectives' include security, geographical restrictions,
maximum occupancy level objectives. The later standard might define
other SLOs as needed.
Editor's Note TODO: replace Minimal set to most commonly used SLOs can be described as 'Directly Measurable Objectives': they are
objectives to describe network behavior. Other directly or always measurable. See Section 4.1.2 for the description of Service
indirectly measurable objectives may be requested by that consumer of Level Expectations which are unmeasurable service-related requests
an IETF Network Slice. sometimes known as 'Indirectly Measurable Objectives'.
Objectives such as guaranteed minimum bandwidth, guaranteed maximum
latency, maximum permissible delay variation, maximum permissible
packet loss rate, and availability are 'Directly Measurable
Objectives'. Future specifications (such as IETF Network Slice
service YANG models) may precisely define these SLOs, and other SLOs
may be introduced as described in Section 4.1.1.2.
The definition of these objectives are as follows: The definition of these objectives are as follows:
Guaranteed Minimum Bandwidth Guaranteed Minimum Bandwidth
Minimum guaranteed bandwidth between two endpoints at any time. Minimum guaranteed bandwidth between two endpoints at any time.
The bandwidth is measured in data rate units of bits per second The bandwidth is measured in data rate units of bits per second
and is measured unidirectionally. and is measured unidirectionally.
Guaranteed Maximum Latency Guaranteed Maximum Latency
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[RFC2681] and [RFC7679] discuss round trip times and one-way [RFC2681] and [RFC7679] discuss round trip times and one-way
metrics, respectively. metrics, respectively.
Maximum Permissible Delay Variation Maximum Permissible Delay Variation
Packet delay variation (PDV) as defined by [RFC3393], is the Packet delay variation (PDV) as defined by [RFC3393], is the
difference in the one-way delay between sequential packets in a difference in the one-way delay between sequential packets in a
flow. This SLO sets a maximum value PDV for packets between flow. This SLO sets a maximum value PDV for packets between
two endpoints. two endpoints.
Maximum permissible packet loss rate Maximum Permissible Packet Loss Rate
The ratio of packets dropped to packets transmitted between two The ratio of packets dropped to packets transmitted between two
endpoints over a period of time. See [RFC7680]. endpoints over a period of time. See [RFC7680].
Availability Availability
The ratio of uptime to the sum of uptime and downtime, where The ratio of uptime to the sum of uptime and downtime, where
uptime is the time the IETF Network Slice is available in uptime is the time the IETF Network Slice is available in
accordance with the SLOs associated with it. accordance with the SLOs associated with it.
Security 4.1.1.2. Other Service Level Objectives
An IETF Network Slice consumer may request that the network Additional SLOs may be defined to provide additional description of
applies encryption or other security techniques to traffic the IETF Network Slice service that a customer requests. These would
flowing between endpoints. be specified in further documents.
Note that the use of security or the violation of this SLO is If the IETF network slice service is traffic aware, other traffic
not directly observable by the IETF Network Slice consumer and specific characteristics may be valuable including MTU, traffic-type
cannot be measured as a quantifiable metric. (e.g., IPv4, IPv6, Ethernet or unstructured), or a higher-level
behavior to process traffic according to user-application (which may
be realized using network functions).
Also note that the objective may include request for encryption 4.1.2. Service Level Expectations
(e.g., [RFC4303]) between the two endpoints explicitly to meet
SLEs define a set of network attributes and characteristics that
describe an IETF Network Slice service, but which are not directly
measurable by the customer. Even though the delivery of an SLE
cannot usually be determined the customer, the SLEs form an important
part of the contract between customer and provider.
Quite often, an SLE will imply some details of how an IETF Network
Slice service is realized by the provider, although most aspects of
the implementation in the underlying network layers remain a free
choice for the provider.
SLEs may be seen as aspirational on the part of the customer, and
they are expressed as behaviors that the provider is expected to
apply to the network resources used to deliver the IETF Network Slice
service. An IETF network slice service can have one or more SLEs
associated with it. The SLEs are combined with SLOs in an SLA.
An IETF Network Slice service may include multiple connection
constructs that associate sets of endpoints. SLEs apply to sets of
two or more endpoints and apply to specific directions of traffic
flow. That is, they apply to a specific source endpoint and the
connection to specific destination endpoints. However, being more
general in nature, SLEs may commonly be applied to all connection
constructs in an IETF Network Slice service.
4.1.2.1. Some Common SLEs
SLEs can be described as 'Indirectly Measurable Objectives': they are
not generally directly measurable by the customer.
Security, geographic restrictions, maximum occupancy level, and
isolation are example SLEs as follows.
Security
A customer may request that the provider applies encryption or
other security techniques to traffic flowing between endpoints
of an IETF Network Slice service. For example, the customer
could request that only network links that have MACsec [MACsec]
enabled are used to realize the IETF Network Slice service.
This SLE may include the request for encryption (e.g.,
[RFC4303]) between the two endpoints explicitly to meet
architecture recommendations as in [TS33.210] or for compliance architecture recommendations as in [TS33.210] or for compliance
with [HIPAA] and/or [PCI]. with [HIPAA] or [PCI].
Please see more discussion on security in Section 9. Whether or not the provider has met this SLE is generally not
directly observable by the customer and cannot be measured as a
quantifiable metric.
4.1.1.2. Other Service Level Objectives Please see further discussion on security in Section 9.
Additional SLOs may be defined to provide additional description of Geographic Restrictions
the IETF Network Slice that a consumer requests.
If the IETF Network Slice consumer service is traffic aware, other A customer may request that certain geographic limits are
traffic specific characteristics may be valuable including MTU, applied to how the provider routes traffic for the IETF Network
traffic-type (e.g., IPv4, IPv6, Ethernet or unstructured), or a Slice service. For example, the customer may have a preference
higher-level behavior to process traffic according to user- that its traffic does not pass through a particular country for
application (which may be realized using network functions). political or security reasons.
Maximal occupancy for an IETF Network Slice should be provided. Whether or not the provider has met this SLE is generally not
Since it carries traffic for multiple flows between the two directly observable by the customer and cannot be measured as a
endpoints, the objectives should also say if they are for the entire quantifiable metric.
connection, group of flows or on per flow basis. Maximal occupancy
should specify the scale of the flows (i.e., maximum number of flows Maximal Occupancy Level
to be admitted) and optionally a maximum number of countable resource
units, e.g., IP or MAC addresses a slice might consume. The maximal occupancy level specifies the number of flows to be
admitted and optionally a maximum number of countable resource
units (e.g., IP or MAC addresses) an IETF network slice service
can consume. Since an IETF Network Slice service may include
multiple connection constructs, this SLE should also say
whether it applies for the entire IETF Network Service slice,
for group of connections, or on a per connection basis.
Again, a customer may not be able to fully determine whether
this SLE is being met by the provider.
Isolation
As described in Section 7, a customer may request that its
traffic within its IETF Network Slice service is isolated from
the effects of other network services supported by the same
provider. That is, if another service exceeds capacity or has
a burst of traffic, the customer's IETF Network Slice service
should remain unaffected and there should be no noticeable
change to the quality of traffic delivered.
In general, a customer cannot tell whether a service provider
is meeting this SLE. They cannot tell whether the variation of
an SLI is because of changes in the underlying network or
because of interference from other services carried by the
network. And if the service varies within the allowed bounds
of the SLOs, there may be no noticeable indication that this
SLE has been violated.
Diversity
A customer may request that traffic on the connection between
one set of endpoints should use different network resources
from the traffic between another set of endpoints. This might
be done to enhance the availability of the IETF Network Slice
service.
While availability is a measurable objective (see
Section 4.1.1.1) this SLE requests a finer grade of control and
is not directly measurable (although the customer might become
suspicious if two connections fail at the same time).
4.2. IETF Network Slice Endpoints 4.2. IETF Network Slice Endpoints
As noted in Section 3.1, an IETF Network Slice describes connectivity As noted in Section 3.1, an IETF Network Slice describes connectivity
between multiple endpoints across the underlying network. These between multiple endpoints across the underlying network. These
connectivity types are: point-to-point, point-to-multipoint, connectivity types are: point-to-point, point-to-multipoint,
multipoint-to-point, multipoint-to-point, or multipoint-to- multipoint-to-point, multipoint-to-point, or multipoint-to-
multipoint. multipoint.
Figure 1 shows an IETF Network Slice along with its Network Slice Figure 1 shows an IETF Network Slice along with its Network Slice
skipping to change at page 10, line 50 skipping to change at page 12, line 38
o Each endpoint could map to a device, application or a network o Each endpoint could map to a device, application or a network
function. A non-exhaustive list of devices, applications or function. A non-exhaustive list of devices, applications or
network functions might include but not limited to: routers, network functions might include but not limited to: routers,
switches, firewalls, WAN, 4G/5G RAN nodes, 4G/5G Core nodes, switches, firewalls, WAN, 4G/5G RAN nodes, 4G/5G Core nodes,
application acceleration, Deep Packet Inspection (DPI), server application acceleration, Deep Packet Inspection (DPI), server
load balancers, NAT44 [RFC3022], NAT64 [RFC6146], HTTP header load balancers, NAT44 [RFC3022], NAT64 [RFC6146], HTTP header
enrichment functions, and TCP optimizers. enrichment functions, and TCP optimizers.
o An NSE should be identified by a unique ID in the context of an o An NSE should be identified by a unique ID in the context of an
IETF Network Slice consumer. IETF Network Slice customer.
o In addition to an identifier, each NSE should contain a subset of o In addition to an identifier, each NSE should contain a subset of
attributes such as IPv4/IPv6 addresses, encapsulation type (i.e., attributes such as IPv4/IPv6 addresses, encapsulation type (i.e.,
VLAN tag, MPLS Label etc.), interface/port numbers, node ID etc. VLAN tag, MPLS Label etc.), interface/port numbers, node ID etc.
o A combination of NSE unique ID and NSE attributes defines an NSE o A combination of NSE unique ID and NSE attributes defines an NSE
in the context of the IETF Network Slice Controller (NSC). in the context of the IETF Network Slice Controller (NSC).
o During the realization of the IETF Network Slice, in addition to o During the realization of the IETF Network Slice, in addition to
SLOs, all or subset of IETF NSE attributes will be utilized by the SLOs, all or subset of IETF NSE attributes will be utilized by the
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sequential composition, each IETF Network Slice would potentially sequential composition, each IETF Network Slice would potentially
support different dataplanes that need to be stitched together. support different dataplanes that need to be stitched together.
5. Framework 5. Framework
A number of IETF Network Slice services will typically be provided A number of IETF Network Slice services will typically be provided
over a shared underlying network infrastructure. Each IETF Network over a shared underlying network infrastructure. Each IETF Network
Slice consists of both the overlay connectivity and a specific set of Slice consists of both the overlay connectivity and a specific set of
dedicated network resources and/or functions allocated in a shared dedicated network resources and/or functions allocated in a shared
underlay network to satisfy the needs of the IETF Network Slice underlay network to satisfy the needs of the IETF Network Slice
consumer. In at least some examples of underlying network customer. In at least some examples of underlying network
technologies, the integration between the overlay and various technologies, the integration between the overlay and various
underlay resources is needed to ensure the guaranteed performance underlay resources is needed to ensure the guaranteed performance
requested for different IETF Network Slices. requested for different IETF Network Slices.
Section 3 of [I-D.ietf-teas-enhanced-vpn] provides an example
architecture that might apply in using the technology described in
this document.
5.1. IETF Network Slice Stakeholders 5.1. IETF Network Slice Stakeholders
An IETF Network Slice and its realization involves the following An IETF Network Slice and its realization involves the following
stakeholders and it is relevant to define them for consistent stakeholders and it is relevant to define them for consistent
terminology. terminology.
Consumer: A consumer is the requester of an IETF Network Slice. Customer: A customer is the requester of an IETF Network Slice.
Consumers may request monitoring of SLOs. A consumer may manage Customers may request monitoring of SLOs. A customer may manage
the IETF Network Slice service directly by interfacing with the the IETF Network Slice service directly by interfacing with the
IETF NSC or indirectly through an orchestrator. IETF NSC or indirectly through an orchestrator.
Orchestrator: An orchestrator is an entity that composes different Orchestrator: An orchestrator is an entity that composes different
services, resource and network requirements. It interfaces with services, resource and network requirements. It interfaces with
the IETF NSC. the IETF NSC.
IETF Network Slice Controller (NSC): It realizes an IETF Network IETF Network Slice Controller (NSC): It realizes an IETF Network
Slice in the underlying network, maintains and monitors the run- Slice in the underlying network, maintains and monitors the run-
time state of resources and topologies associated with it. A time state of resources and topologies associated with it. A
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Network Controller: is a form of network infrastructure controller Network Controller: is a form of network infrastructure controller
that offers network resources to the NSC to realize a particular that offers network resources to the NSC to realize a particular
network slice. These may be existing network controllers network slice. These may be existing network controllers
associated with one or more specific technologies that may be associated with one or more specific technologies that may be
adapted to the function of realizing IETF Network Slices in a adapted to the function of realizing IETF Network Slices in a
network. network.
5.2. Expressing Connectivity Intents 5.2. Expressing Connectivity Intents
The NSC northbound interface (NBI) can be used to communicate between The NSC northbound interface (NBI) can be used to communicate between
IETF Network Slice users (or consumers) and the NSC. IETF Network Slice users (or customers) and the NSC.
An IETF Network Slice user may be a network operator who, in turn, An IETF Network Slice user may be a network operator who, in turn,
provides the IETF Network Slice to another IETF Network Slice user or provides the IETF Network Slice to another IETF Network Slice user or
consumer. customer.
Using the NBI, a consumer expresses requirements for a particular Using the NBI, a customer expresses requirements for a particular
slice by specifying what is required rather than how that is to be slice by specifying what is required rather than how that is to be
achieved. That is, the consumer's view of a slice is an abstract achieved. That is, the customer's view of a slice is an abstract
one. Consumers normally have limited (or no) visibility into the one. Customers normally have limited (or no) visibility into the
provider network's actual topology and resource availability provider network's actual topology and resource availability
information. information.
This should be true even if both the consumer and provider are This should be true even if both the customer and provider are
associated with a single administrative domain, in order to reduce associated with a single administrative domain, in order to reduce
the potential for adverse interactions between IETF Network Slice the potential for adverse interactions between IETF Network Slice
consumers and other users of the underlay network infrastructure. customers and other users of the underlay network infrastructure.
The benefits of this model can include: The benefits of this model can include:
o Security: because the underlay network (or network operator) does o Security: because the underlay network (or network operator) does
not need to expose network details (topology, capacity, etc.) to not need to expose network details (topology, capacity, etc.) to
IETF Network Slice consumers the underlay network components are IETF Network Slice customers the underlay network components are
less exposed to attack; less exposed to attack;
o Layered Implementation: the underlay network comprises network o Layered Implementation: the underlay network comprises network
elements that belong to a different layer network than consumer elements that belong to a different layer network than customer
applications, and network information (advertisements, protocols, applications, and network information (advertisements, protocols,
etc.) that a consumer cannot interpret or respond to (note - a etc.) that a customer cannot interpret or respond to (note - a
consumer should not use network information not exposed via the customer should not use network information not exposed via the
NSC NBI, even if that information is available); NSC NBI, even if that information is available);
o Scalability: consumers do not need to know any information beyond o Scalability: customers do not need to know any information beyond
that which is exposed via the NBI. that which is exposed via the NBI.
The general issues of abstraction in a TE network is described more The general issues of abstraction in a TE network is described more
fully in [RFC7926]. fully in [RFC7926].
This framework document does not assume any particular layer at which This framework document does not assume any particular layer at which
IETF Network Slices operate as a number of layers (including virtual IETF Network Slices operate as a number of layers (including virtual
L2, Ethernet or IP connectivity) could be employed. L2, Ethernet or IP connectivity) could be employed.
Data models and interfaces are of course needed to set up IETF Data models and interfaces are of course needed to set up IETF
Network Slices, and specific interfaces may have capabilities that Network Slices, and specific interfaces may have capabilities that
allow creation of specific layers. allow creation of specific layers.
Layered virtual connections are comprehensively discussed in IETF Layered virtual connections are comprehensively discussed in IETF
documents and are widely supported. See, for instance, GMPLS-based documents and are widely supported. See, for instance, GMPLS-based
networks ([RFC5212] and [RFC4397]), or ACTN ([RFC8453] and networks [RFC5212] and [RFC4397], or Abstraction and Control of TE
[RFC8454]). The principles and mechanisms associated with layered Networks (ACTN) [RFC8453] and [RFC8454]. The principles and
networking are applicable to IETF Network Slices. mechanisms associated with layered networking are applicable to IETF
Network Slices.
There are several IETF-defined mechanisms for expressing the need for There are several IETF-defined mechanisms for expressing the need for
a desired logical network. The NBI carries data either in a a desired logical network. The NBI carries data either in a
protocol-defined format, or in a formalism associated with a modeling protocol-defined format, or in a formalism associated with a modeling
language. language.
For instance: For instance:
o Path Computation Element (PCE) Communication Protocol (PCEP) o Path Computation Element (PCE) Communication Protocol (PCEP)
[RFC5440] and GMPLS User-Network Interface (UNI) using RSVP-TE [RFC5440] and GMPLS User-Network Interface (UNI) using RSVP-TE
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is the key building block for control and management of the IETF is the key building block for control and management of the IETF
Network Slice. It provides the creation/modification/deletion, Network Slice. It provides the creation/modification/deletion,
monitoring and optimization of IETF Network Slices in a multi-domain, monitoring and optimization of IETF Network Slices in a multi-domain,
a multi-technology and multi-vendor environment. a multi-technology and multi-vendor environment.
The main task of the IETF NSC is to map abstract IETF Network Slice The main task of the IETF NSC is to map abstract IETF Network Slice
requirements to concrete technologies and establish required requirements to concrete technologies and establish required
connectivity, and ensuring that required resources are allocated to connectivity, and ensuring that required resources are allocated to
the IETF Network Slice. the IETF Network Slice.
A NSC northbound interface (NBI) is needed for communicating details An NSC northbound interface (NBI) is needed for communicating details
of a IETF Network Slice (configuration, selected policies, of a IETF Network Slice (configuration, selected policies,
operational state, etc.), as well as providing information to a slice operational state, etc.), as well as providing information to a slice
requester/consumer about IETF Network Slice status and performance. requester/customer about IETF Network Slice status and performance.
The details for this NBI are not in scope for this document. The details for this NBI are not in scope for this document.
The controller provides the following functions: The controller provides the following functions:
o Provides a technology-agnostic NBI for creation/modification/ o Provides a technology-agnostic NBI for creation/modification/
deletion of the IETF Network Slices. The API exposed by this NBI deletion of the IETF Network Slices. The API exposed by this NBI
communicates the endpoints of the IETF network slice, IETF Network communicates the endpoints of the IETF network slice, IETF Network
Slice SLO parameters (and possibly monitoring thresholds), Slice SLO parameters (and possibly monitoring thresholds),
applicable input selection (filtering) and various policies, and applicable input selection (filtering) and various policies, and
provides a way to monitor the slice. provides a way to monitor the slice.
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* map filtering/selection information as necessary to entities in * map filtering/selection information as necessary to entities in
the underlay network. the underlay network.
o Via an SBI, the controller collects telemetry data (e.g., OAM o Via an SBI, the controller collects telemetry data (e.g., OAM
results, statistics, states, etc.) for all elements in the results, statistics, states, etc.) for all elements in the
abstract topology used to realize the IETF Network Slice. abstract topology used to realize the IETF Network Slice.
o Using the telemetry data from the underlying realization of a IETF o Using the telemetry data from the underlying realization of a IETF
Network Slice (i.e., services/paths/tunnels), evaluates the Network Slice (i.e., services/paths/tunnels), evaluates the
current performance against IETF Network Slice SLO parameters and current performance against IETF Network Slice SLO parameters and
exposes them to the IETF Network Slice consumer via the NBI. The exposes them to the IETF Network Slice customer via the NBI. The
NSC NBI may also include a capability to provide notification in NSC NBI may also include a capability to provide notification in
case the IETF Network Slice performance reaches threshold values case the IETF Network Slice performance reaches threshold values
defined by the IETF Network Slice consumer. defined by the IETF Network Slice customer.
An IETF Network Slice user is served by the IETF Network Slice An IETF Network Slice user is served by the IETF Network Slice
Controller (NSC), as follows: Controller (NSC), as follows:
o The NSC takes requests from a management system or other o The NSC takes requests from a management system or other
application, which are then communicated via an NBI. This application, which are then communicated via an NBI. This
interface carries data objects the IETF Network Slice user interface carries data objects the IETF Network Slice user
provides, describing the needed IETF Network Slices in terms of provides, describing the needed IETF Network Slices in terms of
topology, applicable service level objectives (SLO), and any topology, applicable service level objectives (SLO), and any
monitoring and reporting requirements that may apply. Note that - monitoring and reporting requirements that may apply. Note that -
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functions. functions.
5.3.1. IETF Network Slice Controller Interfaces 5.3.1. IETF Network Slice Controller Interfaces
The interworking and interoperability among the different The interworking and interoperability among the different
stakeholders to provide common means of provisioning, operating and stakeholders to provide common means of provisioning, operating and
monitoring the IETF Network Slices is enabled by the following monitoring the IETF Network Slices is enabled by the following
communication interfaces (see Figure 2). communication interfaces (see Figure 2).
NSC Northbound Interface (NBI): The NSC Northbound Interface is an NSC Northbound Interface (NBI): The NSC Northbound Interface is an
interface between a consumer's higher level operation system interface between a customer's higher level operation system
(e.g., a network slice orchestrator) and the NSC. It is a (e.g., a network slice orchestrator) and the NSC. It is a
technology agnostic interface. The consumer can use this technology agnostic interface. The customer can use this
interface to communicate the requested characteristics and other interface to communicate the requested characteristics and other
requirements (i.e., the SLOs) for the IETF Network Slice, and the requirements (i.e., the SLOs) for the IETF Network Slice, and the
NSC can use the interface to report the operational state of an NSC can use the interface to report the operational state of an
IETF Network Slice to the consumer. IETF Network Slice to the customer.
NSC Southbound Interface (SBI): The NSC Southbound Interface is an NSC Southbound Interface (SBI): The NSC Southbound Interface is an
interface between the NSC and network controllers. It is interface between the NSC and network controllers. It is
technology-specific and may be built around the many network technology-specific and may be built around the many network
models defined within the IETF. models defined within the IETF.
+------------------------------------------+ +------------------------------------------+
| Consumer higher level operation system | | Customer higher level operation system |
| (e.g E2E network slice orchestrator) | | (e.g E2E network slice orchestrator) |
+------------------------------------------+ +------------------------------------------+
A A
| NSC NBI | NSC NBI
V V
+------------------------------------------+ +------------------------------------------+
| IETF Network Slice Controller (NSC) | | IETF Network Slice Controller (NSC) |
+------------------------------------------+ +------------------------------------------+
A A
| NSC SBI | NSC SBI
V V
+------------------------------------------+ +------------------------------------------+
| Network Controllers | | Network Controllers |
+------------------------------------------+ +------------------------------------------+
Figure 2: Interface of IETF Network Slice Controller Figure 2: Interface of IETF Network Slice Controller
5.3.2. Northbound Interface (NBI) 5.3.2. Northbound Interface (NBI)
The IETF Network Slice Controller provides a Northbound Interface The IETF Network Slice Controller provides a Northbound Interface
(NBI) that allows consumers of network slices to request and monitor (NBI) that allows customers of network slices to request and monitor
IETF Network Slices. Consumers operate on abstract IETF Network IETF Network Slices. Customers operate on abstract IETF Network
Slices, with details related to their realization hidden. Slices, with details related to their realization hidden.
The NBI complements various IETF services, tunnels, path models by The NBI complements various IETF services, tunnels, path models by
providing an abstract layer on top of these models. providing an abstract layer on top of these models.
The NBI is independent of type of network functions or services that The NBI is independent of type of network functions or services that
need to be connected, i.e., it is independent of any specific need to be connected, i.e., it is independent of any specific
storage, software, protocol, or platform used to realize physical or storage, software, protocol, or platform used to realize physical or
virtual network connectivity or functions in support of IETF Network virtual network connectivity or functions in support of IETF Network
Slices. Slices.
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end network slices. A network operator may be responsible for end network slices. A network operator may be responsible for
delivering services over a number of technologies (such as radio delivering services over a number of technologies (such as radio
networks) and for providing specific and fine-grained services (such networks) and for providing specific and fine-grained services (such
as CCTV feed or High definition realtime traffic data). That as CCTV feed or High definition realtime traffic data). That
operator may need to combine slices of various networks to produce an operator may need to combine slices of various networks to produce an
end-to-end network service. Each of these networks may include end-to-end network service. Each of these networks may include
multiple physical or virtual nodes and may also provide network multiple physical or virtual nodes and may also provide network
functions beyond simply carrying of technology-specific protocol data functions beyond simply carrying of technology-specific protocol data
units. An end-to-end network slice is defined by the 3GPP as a units. An end-to-end network slice is defined by the 3GPP as a
complete logical network that provides a service in its entirety with complete logical network that provides a service in its entirety with
a specific assurance to the consumer [TS23501]. a specific assurance to the customer [TS23501].
An end-to-end network slice may be composed from other network slices An end-to-end network slice may be composed from other network slices
that include IETF Network Slices. This composition may include the that include IETF Network Slices. This composition may include the
hierarchical (or recursive) use of underlying network slices and the hierarchical (or recursive) use of underlying network slices and the
sequential (or stitched) combination of slices of different networks. sequential (or stitched) combination of slices of different networks.
5.5. Realizing IETF Network Slice 6. Realizing IETF Network Slices
Realization of IETF Network Slices is out of scope of this document. Realization of IETF Network Slices is out of scope of this document.
It is a mapping of the definition of the IETF Network Slice to the It is a mapping of the definition of the IETF Network Slice to the
underlying infrastructure and is necessarily technology-specific and underlying infrastructure and is necessarily technology-specific and
achieved by the NSC over the SBI. achieved by the NSC over the SBI.
The realization can be achieved in a form of either physical or The realization can be achieved in a form of either physical or
logical connectivity through VPNs (see, for example, logical connectivity using VPNs, virtual networks (VNs), or a variety
[I-D.ietf-teas-enhanced-vpn], a variety of tunneling technologies of tunneling technologies such as Segment Routing, MPLS, etc.
such as Segment Routing, MPLS, etc. Accordingly, endpoints may be Accordingly, endpoints (NSEs) may be realized as physical or logical
realized as physical or logical service or network functions. service or network functions.
5.5.1. Underlying Technology
There are a number of different technologies that can be used,
including physical connections, MPLS, TSN, Flex-E, etc.
See Section 5 of [I-D.ietf-teas-enhanced-vpn] for instance, for 6.1. Procedures to Realize IETF Network Slices
example underlying technologies.
Also, as outlined in "applicability of ACTN to IETF Network Slices" There are a number of different technologies that can be used in the
below, ACTN ([RFC8453]) offers a framework that is used elsewhere in underlay, including physical connections, MPLS, time-sensitive
IETF specifications to create virtual network (VN) services similar networking (TSN), Flex-E, etc.
to IETF Network Slices.
A IETF Network Slice can be realized in a network, using specific An IETF Network Slice can be realized in a network, using specific
underlying technology or technologies. The creation of a new IETF underlying technology or technologies. The creation of a new IETF
Network Slice will be initiated with following three steps: Network Slice will be initiated with following three steps:
o Step 1: A higher level system requests connections with specific o Step 1: A higher level system requests connections with specific
characteristics via NBI. characteristics via the NBI.
o Step 2: This request will be processed by an IETF NSC which o Step 2: This request will be processed by an IETF NSC which
specifies a mapping between northbound request to any IETF specifies a mapping between northbound request to any IETF
Services, Tunnels, and paths models. Services, Tunnels, and paths models.
o Step 3: A series of requests for creation of services, tunnels and o Step 3: A series of requests for creation of services, tunnels and
paths will be sent to the network to realize the trasport slice. paths will be sent to the network to realize the transport slice.
It is very clear that regardless of how IETF Network Slice is
realized in the network (i.e., using tunnels of type RSVP or SR), the
definition of IETF Network Slice does not change at all but rather
its realization.
6. Applicability of ACTN to IETF Network Slices
Abstraction and Control of TE Networks (ACTN - [RFC8453]) is an
example of similar IETF work. ACTN defines three controllers to
support virtual network (VN) services -
o Customer Network Controller (CNC),
o Multi-Domain Service Coordinator (MDSC) and
o Provisioning Network Controller (PNC). It is very clear that, regardless of how IETF Network Slice is
realized in the network (i.e., using tunnels of different types), the
definition of the IETF Network Slice does not change at all. The
only difference is how the slice is realized. The following sections
briefly introduce some existing architectural approaches that can be
applied to realize IETF Network Slices.
A CNC is responsible for communicating a customer's VN requirements. 6.2. Applicability of ACTN to IETF Network Slices
A MDSC is responsible for multi-domain coordination, virtualization Abstraction and Control of TE Networks (ACTN - [RFC8453]) is a
(or abstraction), customer mapping/translation and virtual service management architecture and toolkit used to create virtual networks
coordination to realize the VN requirement. Its key role is to (VNs) on top of a traffic engineering (TE) underlay network. The VNs
detach the network/service requirements from the underlying can be presented to customers for them to operate as private
technology. networks.
A PNC oversees the configuration, monitoring and collection of the In many ways, the function of ACTN is similar to IETF network
network topology. The PNC is a underlay technology specific slicing. Customer requests for connectivity-based overlay services
controller. are mapped to dedicated or shared resources in the underlay network
in a way that meets customer guarantees for service level objectives
and for separation from other customers' traffic. [RFC8453] the
function of ACTN as collecting resources to establish a logically
dedicated virtual network over one or more TE networks. Thus, in the
case of a TE-enabled underlying network, the ACTN VN can be used as a
basis to realize an IETF network slicing.
While the ACTN framework is a generic VN framework that is used for While the ACTN framework is a generic VN framework that can be used
various VN service beyond the IETF Network Slice, it is still a for VN services beyond the IETF network slice, it also a suitable
suitable basis to understand how the various controllers interact to basis for delivering and realizing IETF network slices.
realize a IETF Network Slice.
One possible mapping between the IETF Network Slice, and ACTN, Further discussion of the applicability of ACTN to IETF network
definitions is as shown in Figure 4. slices including a discussion of the relevant YANG models can be
found in [I-D.king-teas-applicability-actn-slicing].
IETF Network Slice | ACTN analogous 6.3. Applicability of Enhanced VPNs to IETF Network Slices
Terminology / Concepts Terminology
| and Concepts
+--------------------------------------+
|Consumer higher level operation system| | +-----+
| (e.g E2E network slice orchestrator) | =====> | CNC |
+--------------------------------------+ | +-----+
^ ^
| NSC NBI | | CMI
v v
+-------------------------------------+ | +------+
| IETF Network Slice Controller (NSC) | =====> | MDSC |
+-------------------------------------+ | +------+
^ ^
| NSC SBI | | MPI
v v
+-------------------------------------+ | +-----+
| Network Controller(s) | =====> | PNC |
+-------------------------------------+ | +-----+
Figure 4: Mapping between IETF Network Slices and ACTN An enhanced VPN (VPN+) is designed to support the needs of new
applications, particularly applications that are associated with 5G
services, by utilizing an approach that is based on existing VPN and
Traffic Engineering (TE) technologies and adds characteristics that
specific services require over and above traditional VPNs.
The NSC NBI conveys the generic IETF Network Slice requirements. An enhanced VPN can be used to provide enhanced connectivity services
These may then be realized using an SBI within the NSC. between customer sites (a concept similar to an IETF Network Slice)
and can be used to create the infrastructure to underpin network
slicing.
As per [RFC8453] and [I-D.ietf-teas-actn-yang], the CNC-MDSC It is envisaged that enhanced VPNs will be delivered using a
Interface (CMI) is used to convey the virtual network service combination of existing, modified, and new networking technologies.
requirements along with the service models and the MDSC-PNC Interface
(MPI) is used to realize the service along network configuration
models. [I-D.ietf-teas-te-service-mapping-yang] further describe how
the VPN services can be mapped to the underlying TE resources.
The Network Controller is depicted as a single block, analogous to a [I-D.ietf-teas-enhanced-vpn] describes the framework for Enhanced
Provisioning Network Controller (PNC - in this example). In the ACTN Virtual Private Network (VPN+) services.
framework, however, it is also possible that the NC function is
decomposed into MDSC and PNC - that is, the NC may comprise hierarchy
as needed to handle the multiple domains and various underlay
technologies, whereas a PNC in ACTN is intended to be specific to at
most a single underlay technology and (likely) to individual devices
(or functional components).
Note that the details of potential implementations of everything that 6.4. Network Slicing and Slice Aggregation in IP/MPLS Networks
is below the NSC in Section 6 are out of scope in this document -
hence the specifics of the relationship between NC and PNC, and the
possibility that the MDSC and PNC may be combined are at most
academically interesting in this context. Another way to view this
is that, in the same way that ACTN might combine MDSC and PNC, the
NSC might also directly include NC functionality.
[RFC8453] also describes TE Network Slicing in the context of ACTN as Network slicing provides the ability to partition a physical network
a collection of resources that is used to establish a logically into multiple isolated logical networks of varying sizes, structures,
dedicated virtual network over one or more TE networks. In case of and functions so that each slice can be dedicated to specific
TE enabled underlying network, ACTN VN can be used as a base to services or customers.
realize the IETF Network Slicing by coordination among multiple peer
domains as well as underlay technology domains.
Section 6 shows only one possible mapping as each ACTN component (or Many approaches are currently being worked on to support IETF Network
interface) in the figure may be a composed differently in other Slices in IP and MPLS networks with or without the use of Segment
mappings, and the exact role of both components and subcomponents Routing. Most of these approaches utilize a way of marking packets
will not be always an exact analogy between the concepts used in this so that network nodes can apply specific routing and forwarding
document and those defined in ACTN. behaviors to packets that belong to different IETF Network Slices.
Different mechanisms for marking packets have been proposed
(including using MPLS labels and Segment Rouing segment IDs) and
those mechanisms are agnostic to the path control technology used
within the underlay network.
This is - in part - shown in a previous paragraph in this section These approaches are also sensitive to the scaling concerns of
where it is pointed out that the NC may actually subsume some aspects supporting a large number of IETF Network Slices within a single IP
of both the MDSC and PNC. or MPLS network, and so offer ways to aggregate the slices so that
the packet markings indicate an aggregate or grouping of IETF Network
Slices where all of the packets are subject to the same routing and
forwarding behavior.
Similarly, in part depending on how "customer" is interpreted, CNC At this stage, it is inappropriate to mention any of these proposed
might merge some aspects of the higher level system and the NSC. As solutions that are currently work in progress and not yet adopted as
in the NC/PNC case, this way of comparing ACTN to this work is not IETF work.
useful as the NSC and NSC NBI are the focus on this document.
7. Isolation in IETF Network Slices 7. Isolation in IETF Network Slices
An IETF Network Slice consumer may request, that the IETF Network
Slice delivered to them is isolated from any other network slices of
services delivered to any other consumers. It is expected that the
changes to the other network slices of services do not have any
negative impact on the delivery of the IETF Network Slice.
7.1. Isolation as a Service Requirement 7.1. Isolation as a Service Requirement
Isolation may be an important requirement of IETF Network Slices for An IETF network slice customer may request that the IETF network
some critical services. A consumer may express this request as an slice delivered to them is delivered such that changes to other IETF
SLO. network slices or services do not have any negative impact on the
delivery of the IETF Network Slice. The IETF Network Slice customer
This requirement can be met by simple conformance with other SLOs. may specify the degree to which their IETF Network Slice is
For example, traffic congestion (interference from other services) unaffected by changes in the provider network or by the behavior of
might impact on the latency experienced by an IETF Network Slice. other IETF Network Slice customers. The customer may express this
Thus, in this example, conformance to a latency SLO would be the via an SLE it agrees with the provider. This concept is termed
primary requirement for delivery of the IETF Network Slice service, 'isolation'
and isolation from other services might be only a means to that end.
It should be noted that some aspects of isolation may be measurable
by a consumer who have the information about the traffic on a number
of IETF Network Slices or other services.
7.2. Isolation in IETF Network Slice Realization 7.2. Isolation in IETF Network Slice Realization
Delivery of isolation is achieved in the realization of IETF Network
Slices, with existing, in-development, and potential new technologies
in IETF. It depends on how a network operator decides to operate
their network and deliver services.
Isolation may be achieved in the underlying network by various forms Isolation may be achieved in the underlying network by various forms
of resource partitioning ranging from dedicated allocation of of resource partitioning ranging from dedicated allocation of
resources for a specific IETF Network Slice, to sharing or resources resources for a specific IETF Network Slice, to sharing of resources
with safeguards. For example, traffic separation between different with safeguards. For example, traffic separation between different
IETF Network Slices may be achieved using VPN technologies, such as IETF Network Slices may be achieved using VPN technologies, such as
L3VPN, L2VPN, EVPN, etc. Interference avoidance may be achieved by L3VPN, L2VPN, EVPN, etc. Interference avoidance may be achieved by
network capacity planning, allocating dedicated network resources, network capacity planning, allocating dedicated network resources,
traffic policing or shaping, prioritizing in using shared network traffic policing or shaping, prioritizing in using shared network
resources, etc. Finally, service continuity may be ensured by resources, etc. Finally, service continuity may be ensured by
reserving backup paths for critical traffic, dedicating specific reserving backup paths for critical traffic, dedicating specific
network resources for a selected number of network slices, etc. network resources for a selected number of IETF Network Slices.
8. Management Considerations 8. Management Considerations
IETF Network Slice realization needs to be instrumented in order to IETF Network Slice realization needs to be instrumented in order to
track how it is working, and it might be necessary to modify the IETF track how it is working, and it might be necessary to modify the IETF
Network Slice as requirements change. Dynamic reconfiguration might Network Slice as requirements change. Dynamic reconfiguration might
be needed. be needed.
9. Security Considerations 9. Security Considerations
This document specifies terminology and has no direct effect on the This document specifies terminology and has no direct effect on the
security of implementations or deployments. In this section, a few security of implementations or deployments. In this section, a few
of the security aspects are identified. of the security aspects are identified.
o Conformance to security constraints: Specific security requests o Conformance to security constraints: Specific security requests
from consumer defined IETF Network Slices will be mapped to their from customer defined IETF Network Slices will be mapped to their
realization in the unerlay networks. It will be required by realization in the underlay networks. It will be required by
underlay networks to have capabilities to conform to consumer's underlay networks to have capabilities to conform to customer's
requests as some aspects of security may be expressed in SLOs. requests as some aspects of security may be expressed in SLOs.
o IETF NSC authentication: Unerlying networks need to be protected o IETF NSC authentication: Underlying networks need to be protected
against the attacks from an adversary NSC as they can destablize against the attacks from an adversary NSC as they can destabilize
overall network operations. It is particularly critical since an overall network operations. It is particularly critical since an
IETF Network Slice may span across different networks, therefore, IETF Network Slice may span across different networks, therefore,
IETF NSC should have strong authentication with each those IETF NSC should have strong authentication with each those
networks. Futhermore, both SBI and NBI need to be secured. networks. Furthermore, both SBI and NBI need to be secured.
o Specific isolation criteria: The nature of conformance to o Specific isolation criteria: The nature of conformance to
isolation requests means that it should not be possible to attack isolation requests means that it should not be possible to attack
an IETF Network Slice service by varying the traffic on other an IETF Network Slice service by varying the traffic on other
services or slices carried by the same underlay network. In services or slices carried by the same underlay network. In
general, isolation is expected to strengthen the IETF Network general, isolation is expected to strengthen the IETF Network
Slice security. Slice security.
o Data Integrity of an IETF Network Slice: A consumer wanting to o Data Integrity of an IETF Network Slice: A customer wanting to
secure their data and keep it private will be responsible for secure their data and keep it private will be responsible for
applying appropriate security measures to their traffic and not applying appropriate security measures to their traffic and not
depending on the network operator that provides the IETF Network depending on the network operator that provides the IETF Network
Slice. It is expected that for data integrity, a consumer is Slice. It is expected that for data integrity, a customer is
responsible for end-to-end encryption of its own traffic. responsible for end-to-end encryption of its own traffic.
Note: see NGMN document[NGMN_SEC] on 5G network slice security for Note: see NGMN document[NGMN_SEC] on 5G network slice security for
discussion relevant to this section. discussion relevant to this section.
IETF Network Slices might use underlying virtualized networking. All IETF Network Slices might use underlying virtualized networking. All
types of virtual networking require special consideration to be given types of virtual networking require special consideration to be given
to the separation of traffic between distinct virtual networks, as to the separation of traffic between distinct virtual networks, as
well as some degree of protection from effects of traffic use of well as some degree of protection from effects of traffic use of
underlying network (and other) resources from other virtual networks underlying network (and other) resources from other virtual networks
skipping to change at page 25, line 40 skipping to change at page 25, line 33
then that service can be degraded by added delay in transmission of then that service can be degraded by added delay in transmission of
service packets through the activities of another service or service packets through the activities of another service or
application using the same resources. application using the same resources.
Similarly, in a network with virtual functions, noticeably impeding Similarly, in a network with virtual functions, noticeably impeding
access to a function used by another IETF Network Slice (for access to a function used by another IETF Network Slice (for
instance, compute resources) can be just as service degrading as instance, compute resources) can be just as service degrading as
delaying physical transmission of associated packet in the network. delaying physical transmission of associated packet in the network.
While a IETF Network Slice might include encryption and other While a IETF Network Slice might include encryption and other
security features as part of the service, consumers might be well security features as part of the service, customers might be well
advised to take responsibility for their own security needs, possibly advised to take responsibility for their own security needs, possibly
by encrypting traffic before hand-off to a service provider. by encrypting traffic before hand-off to a service provider.
9.1. Privacy Considerations 10. Privacy Considerations
Privacy of IETF Network Slice service consumers must be preserved. Privacy of IETF Network Slice service customers must be preserved.
It should not be possible for one IETF Network Slice consumer to It should not be possible for one IETF Network Slice customer to
discover the presence of other consumers, nor should sites that are discover the presence of other customers, nor should sites that are
members of one IETF Network Slice be visible outside the context of members of one IETF Network Slice be visible outside the context of
that IETF Network Slice. that IETF Network Slice.
In this sense, it is of paramount importance that the system use the In this sense, it is of paramount importance that the system use the
privacy protection mechanism defined for the specific underlying privacy protection mechanism defined for the specific underlying
technologies used, including in particular those mechanisms designed technologies used, including in particular those mechanisms designed
to preclude acquiring identifying information associated with any to preclude acquiring identifying information associated with any
IETF Network Slice consumer. IETF Network Slice customer.
10. IANA Considerations
There are no requests to IANA in this framework document.
11. Acknowledgments
The entire TEAS NS design team and everyone participating in related
discussions has contributed to this document. Some text fragments in
the document have been copied from the [I-D.ietf-teas-enhanced-vpn],
for which we are grateful.
Significant contributions to this document were gratefully received
from the contributing authors listed in the "Contributors" section.
In addition we would like to also thank those others who have
attended one or more of the design team meetings, including the
following people not listed elsewhere:
o Aihua Guo
o Bo Wu
o Greg Mirsky
o Lou Berger
o Rakesh Gandhi
o Ran Chen
o Sergio Belotti
o Stewart Bryant
o Tomonobu Niwa
o Xuesong Geng
12. Contributors
The following authors contributed significantly to this document:
Jari Arkko
Ericsson
Email: jari.arkko@piuha.net
Dhruv Dhody
Huawei, India
Email: dhruv.ietf@gmail.com
Jie Dong
Huawei
Email: jie.dong@huawei.com
Xufeng Liu
Volta Networks
Email: xufeng.liu.ietf@gmail.com
13. References
13.1. Normative References
[I-D.ietf-teas-ietf-network-slice-definition] 11. IANA Considerations
Rokui, R., Homma, S., Makhijani, K., Contreras, L., and J.
Tantsura, "Definition of IETF Network Slices", draft-ietf-
teas-ietf-network-slice-definition-00 (work in progress),
January 2021.
[I-D.ietf-teas-ietf-network-slice-framework] This document makes no requests for IANA action.
Gray, E. and J. Drake, "Framework for IETF Network
Slices", draft-ietf-teas-ietf-network-slice-framework-00
(work in progress), March 2021.
13.2. Informative References 12. Informative References
[BBF-SD406] [BBF-SD406]
Broadband Forum, ., "End-to-end network slicing", BBF Broadband Forum, "End-to-end network slicing", BBF SD-406,
SD-406 , n.d.. <https://wiki.broadband-forum.org/display/BBF/SD-406+End-
to-End+Network+Slicing>.
[HIPAA] HHS, "Health Insurance Portability and Accountability Act [HIPAA] HHS, "Health Insurance Portability and Accountability Act
- The Security Rule", February 2003, - The Security Rule", February 2003,
<https://www.hhs.gov/hipaa/for-professionals/security/ <https://www.hhs.gov/hipaa/for-professionals/security/
index.html>. index.html>.
[I-D.contreras-teas-slice-nbi]
Contreras, L., Homma, S., and J. Ordonez-Lucena, "IETF
Network Slice use cases and attributes for Northbound
Interface of controller", draft-contreras-teas-slice-
nbi-03 (work in progress), October 2020.
[I-D.ietf-teas-actn-yang]
Lee, Y., Zheng, H., Ceccarelli, D., Yoon, B., Dios, O.,
Shin, J., and S. Belotti, "Applicability of YANG models
for Abstraction and Control of Traffic Engineered
Networks", draft-ietf-teas-actn-yang-06 (work in
progress), August 2020.
[I-D.ietf-teas-enhanced-vpn] [I-D.ietf-teas-enhanced-vpn]
Dong, J., Bryant, S., Li, Z., Miyasaka, T., and Y. Lee, "A Dong, J., Bryant, S., Li, Z., Miyasaka, T., and Y. Lee, "A
Framework for Enhanced Virtual Private Networks (VPN+) Framework for Enhanced Virtual Private Network (VPN+)
Service", draft-ietf-teas-enhanced-vpn-06 (work in Services", draft-ietf-teas-enhanced-vpn-07 (work in
progress), July 2020. progress), February 2021.
[I-D.ietf-teas-te-service-mapping-yang] [I-D.king-teas-applicability-actn-slicing]
Lee, Y., Dhody, D., Fioccola, G., WU, Q., Ceccarelli, D., King, D., Drake, J., Zheng, H., and A. Farrel,
and J. Tantsura, "Traffic Engineering (TE) and Service "Applicability of Abstraction and Control of Traffic
Mapping Yang Model", draft-ietf-teas-te-service-mapping- Engineered Networks (ACTN) to Network Slicing", draft-
yang-05 (work in progress), November 2020. king-teas-applicability-actn-slicing-10 (work in
progress), March 2021.
[I-D.openconfig-rtgwg-gnmi-spec] [I-D.openconfig-rtgwg-gnmi-spec]
Shakir, R., Shaikh, A., Borman, P., Hines, M., Lebsack, Shakir, R., Shaikh, A., Borman, P., Hines, M., Lebsack,
C., and C. Morrow, "gRPC Network Management Interface C., and C. Morrow, "gRPC Network Management Interface
(gNMI)", draft-openconfig-rtgwg-gnmi-spec-01 (work in (gNMI)", draft-openconfig-rtgwg-gnmi-spec-01 (work in
progress), March 2018. progress), March 2018.
[MACsec] IEEE, "IEEE Standard for Local and metropolitan area
networks - Media Access Control (MAC) Security", 2018,
<https://1.ieee802.org/security/802-1ae>.
[NGMN-NS-Concept] [NGMN-NS-Concept]
NGMN Alliance, ., "Description of Network Slicing NGMN Alliance, "Description of Network Slicing Concept",
Concept", https://www.ngmn.org/uploads/ https://www.ngmn.org/uploads/
media/161010_NGMN_Network_Slicing_framework_v1.0.8.pdf , media/161010_NGMN_Network_Slicing_framework_v1.0.8.pdf ,
2016. 2016.
[NGMN_SEC] [NGMN_SEC]
NGMN Alliance, "NGMN 5G Security - Network Slicing", April NGMN Alliance, "NGMN 5G Security - Network Slicing", April
2016, <https://www.ngmn.org/wp-content/uploads/Publication 2016, <https://www.ngmn.org/wp-content/uploads/Publication
s/2016/160429_NGMN_5G_Security_Network_Slicing_v1_0.pdf>. s/2016/160429_NGMN_5G_Security_Network_Slicing_v1_0.pdf>.
[PCI] PCI Security Standards Council, "PCI DSS", May 2018, [PCI] PCI Security Standards Council, "PCI DSS", May 2018,
<https://www.pcisecuritystandards.org>. <https://www.pcisecuritystandards.org>.
skipping to change at page 31, line 30 skipping to change at page 29, line 46
Yoon, "Information Model for Abstraction and Control of TE Yoon, "Information Model for Abstraction and Control of TE
Networks (ACTN)", RFC 8454, DOI 10.17487/RFC8454, Networks (ACTN)", RFC 8454, DOI 10.17487/RFC8454,
September 2018, <https://www.rfc-editor.org/info/rfc8454>. September 2018, <https://www.rfc-editor.org/info/rfc8454>.
[RFC8795] Liu, X., Bryskin, I., Beeram, V., Saad, T., Shah, H., and [RFC8795] Liu, X., Bryskin, I., Beeram, V., Saad, T., Shah, H., and
O. Gonzalez de Dios, "YANG Data Model for Traffic O. Gonzalez de Dios, "YANG Data Model for Traffic
Engineering (TE) Topologies", RFC 8795, Engineering (TE) Topologies", RFC 8795,
DOI 10.17487/RFC8795, August 2020, DOI 10.17487/RFC8795, August 2020,
<https://www.rfc-editor.org/info/rfc8795>. <https://www.rfc-editor.org/info/rfc8795>.
[TS23501] 3GPP, ., "System architecture for the 5G System (5GS)", [TS23501] 3GPP, "System architecture for the 5G System (5GS)",
3GPP TS 23.501 , 2019. 3GPP TS 23.501, 2019.
[TS28530] 3GPP, ., "Management and orchestration; Concepts, use [TS28530] 3GPP, "Management and orchestration; Concepts, use cases
cases and requirements", 3GPP TS 28.530 , 2019. and requirements", 3GPP TS 28.530, 2019.
[TS33.210] [TS33.210]
3GPP, "3G security; Network Domain Security (NDS); IP 3GPP, "3G security; Network Domain Security (NDS); IP
network layer security (Release 14).", December 2016, network layer security (Release 14).", December 2016,
<https://portal.3gpp.org/desktopmodules/Specifications/ <https://portal.3gpp.org/desktopmodules/Specifications/
SpecificationDetails.aspx?specificationId=2279>. SpecificationDetails.aspx?specificationId=2279>.
Appendix A. Unused Material Acknowledgments
This section includes material from the source documents that is not The entire TEAS Network Slicing design team and everyone
used in the body of this document. It is intended for deletion. participating in related discussions has contributed to this
document. Some text fragments in the document have been copied from
the [I-D.ietf-teas-enhanced-vpn], for which we are grateful.
For this purpose, the text is tagged to show its origin using the Significant contributions to this document were gratefully received
format <D1.3> or <F2.4> where the letters 'D' and 'F' indicate the from the contributing authors listed in the "Contributors" section.
definitions draft [I-D.ietf-teas-ietf-network-slice-definition] and In addition we would like to also thank those others who have
the framework draft [I-D.ietf-teas-ietf-network-slice-framework] attended one or more of the design team meetings, including the
respectively, and the subsequent numbers indicate the the section of following people not listed elsewhere:
the source document.
A.1. Abstract o Aihua Guo
<FAb> o Bo Wu
This memo is intended for discussing interfaces and technologies. It o Greg Mirsky
is not intended to be a new set of concrete interfaces or
technologies. Rather, it should be seen as an explanation of how
some existing, concrete IETF VPN and traffic-engineering technologies
can be used to create IETF network slices. Note that there are a
number of these technologies, and new technologies or capabilities
keep being added. This memo is also not intended presume any
particular technology choice.
A.2. Management Systems or Other Applications o Lou Berger
<F3.1.> o Rakesh Gandhi
The IETF Network Slice system is used by a management system or other o Ran Chen
application. These systems and applications may also be a part of a
higher level function in the system, e.g., putting together network o Sergio Belotti
functions, access equipment, application specific components, as well
as the IETF Network Slices. o Stewart Bryant
o Tomonobu Niwa
o Xuesong Geng
Further useful comments were received from Daniele Ceccarelli, Uma
Chunduri, Pavan Beeram, and Tarek Saad.
Contributors
The following authors contributed significantly to this document:
Jari Arkko
Ericsson
Email: jari.arkko@piuha.net
Dhruv Dhody
Huawei, India
Email: dhruv.ietf@gmail.com
Jie Dong
Huawei
Email: jie.dong@huawei.com
Xufeng Liu
Volta Networks
Email: xufeng.liu.ietf@gmail.com
Authors' Addresses Authors' Addresses
Adrian Farrel (editor) Adrian Farrel (editor)
Old Dog Consulting Old Dog Consulting
UK
Email: adrian@olddog.co.uk Email: adrian@olddog.co.uk
Eric Gray Eric Gray
Ericsson Independent
USA
Email: ewgray@graiymage.com Email: ewgray@graiymage.com
John Drake John Drake
Juniper Networks Juniper Networks
USA
Email: jdrake@juniper.net Email: jdrake@juniper.net
Reza Rokui Reza Rokui
Nokia Nokia
Email: reza.rokui@nokia.com Email: reza.rokui@nokia.com
Shunsuke Homma Shunsuke Homma
NTT NTT
Japan
Email: shunsuke.homma.ietf@gmail.com Email: shunsuke.homma.ietf@gmail.com
Kiran Makhijani Kiran Makhijani
Futurewei Futurewei
USA
Email: kiranm@futurewei.com Email: kiranm@futurewei.com
Luis M. Contreras Luis M. Contreras
Telefonica Telefonica
Spain Spain
Email: luismiguel.contrerasmurillo@telefonica.com Email: luismiguel.contrerasmurillo@telefonica.com
Jeff Tantsura Jeff Tantsura
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