Internet DRAFT - draft-irtf-nmrg-ibn-intent-classification
draft-irtf-nmrg-ibn-intent-classification
Network Working Group C. Li
Internet Draft China Telecom
Intended status: Informational O. Havel
Expires: November 2022 A. Olariu
Huawei Technologies
P. Martinez-Julia
NICT
J. Nobre
UFRGS
D. Lopez
Telefonica, I+D
May 18, 2022
Intent Classification
draft-irtf-nmrg-ibn-intent-classification-08
Abstract
Intent is an abstract, high-level policy used to operate the network.
Intent-based management system includes an interface for users to
input requests and an engine to translate the intents into the
network configuration and manage their life-cycle.
This document discusses mostly the concept of network intents, but
other types of intents are also being considered. Specifically, it
highlights stakeholder perspectives of intent, methods to classify
and encode intent, the associated intent taxonomy, and defines
relevant intent terms where necessary. This document provides a
foundation for intent related research and facilitates solution
development.
This document is a product of the IRTF Network Management Research
Group (NMRG).
Status of this Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
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time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on November 18, 2022.
Copyright Notice
Copyright (c) 2022 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
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described in the Simplified BSD License.
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Table of Contents
1. Introduction...................................................4
1.1. Research activities..........................................4
1.2. Standards and open source activities.........................5
1.3. Scope........................................................6
2. Acronyms.......................................................7
3. Definitions....................................................8
4. Abstract Intent Requirements...................................8
4.1. What is Intent?..............................................8
4.2. Intent Solutions and Intent Users............................9
4.3. Benefits of Intents for Different Stakeholders..............11
4.4. Intent Types that need to be supported......................12
5. Functional Characteristics and Behaviour......................13
5.1. Abstracting Intent Operation................................13
5.2. Intent User Types...........................................14
5.3. Intent Scope................................................15
5.4. Intent Network Scope........................................15
5.5. Intent Abstraction..........................................16
5.6. Intent Life-cycle...........................................16
5.7. Autonomous Driving Levels...................................16
6. Intent Classification.........................................17
6.1. Intent Classification Methodology...........................18
6.2. Intent Taxonomy.............................................21
6.3. Intent Classification for Carrier Solution..................23
6.3.1. Intent Users and Intent Types.............................23
6.3.2. Intent Categories.........................................27
6.3.3. Intent Classification Example.............................27
6.4. Intent Classification for Data Center Network Solutions.....31
6.4.1. Intent Users and Intent Types.............................31
6.4.2. Intent Categories.........................................35
6.4.3. Intent Classification Example.............................35
6.5. Intent Classification for Enterprise Solution...............39
6.5.1. Intent Users and Intent Types.............................39
6.5.2. Intent Categories.........................................41
7. Conclusions...................................................43
8. Security Considerations.......................................43
9. IANA Considerations...........................................43
10. Contributors.................................................44
11. Acknowledgments..............................................44
12. Informative References.......................................44
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1. Introduction
The vision of intent-based networks has attracted a lot of attention,
as it promises to simplify the management of networks by human
operators. This is done by simply specifying what should happen on
the network, without giving any instructions on how to do it. This
promise led many researcher-led activities and telecom companies to
start researching this new vision, and many Standards Development
Organization (SDOs) to propose different intent frameworks.
This draft proposes an intent classification methodology and an
intent taxonomy. The scope of these proposals is to ensure a common
understanding in the research community in terms of what are the
intent users, intent types, or intent solutions, etc. for specific
scenarios that are being considered.
The document represents the consensus of the Network Management
Research Group (NMRG). It has been reviewed extensively by the
Research Group (RG) members who are actively involved in the research
and development of the technology covered by this document. It is not
an IETF product and is not a standard.
1.1. Research activities
Intent-based networking is an active research topic which spans
across different areas that could benefit from an intent
classification and taxonomy.
One such area is intent expression and recognition ([Bezahaf21],
[Bezahaf19]), NILE [Jacobs18]). The use of a common classification
can provide consistency in the understanding of the various forms of
intent expressions being proposed and investigated.
Another area where this intent classification could contribute is the
orchestration of cognitive autonomous RANs [Banerjee21] where intents
are classified based on their content.
The work carried in intent network verification [Tian19] where the
authors are proposing new intent language is another candidate where
intent classification could be used advantageously.
Furthermore, this draft is proving itself already extremely relevant
to the research community as it has been used as the basis for
proposing self-generated Intent-based systems [Bezhaf19], for
advancing IBN-based VNF placement solutions that rely on defining
user intent profiles corresponding to abstract network services
[Leivadeas21], for improving existing solutions in provisioning
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intent-based networks, and proposing new approaches to service
management [Davoli21], or even for defining grammars for users to
specify the high-level requirements for blockchain selection in the
form of intent [Padovan20]. As well, the draft has been mentioned in
surveys addressing the topic of intelligent intent-based autonomous
networks [Mehmood21], [Szilagyi21].
This document describes as well an example on how this proposal has
been successfully applied in an academic environment [IBN-POC] by
researchers in the area of SDN/NFV for defining the scope of their
project. The specific problem addressed by researches is how to
apply intent concepts at different levels that correspond to
different stakeholders.
IEEE Communications Society Technical Committee on Network Operation
and Management (IEEE-CNOM), IRTF-NMRG and IFIP WG6.6 have developed a
taxonomy for network and service management [IFIP-NSM] that is used
by the research community in network management and operations to
structure the research area through a well-defined set of keywords
and to improve quality of reviews in submissions to journals,
conferences and workshops. The proposed intent taxonomy may be
contributed as an extension to this taxonomy for intent driven
management.
1.2. Standards and open source activities
Several SDOs and open source projects, such as Internet Research Task
Force (IRTF)/ Network Management Research Group (NMRG), Open
Networking Foundation (ONF) [ONF] / Open Network Operating System
(ONOS) [ONOS], European Telecommunications Standards Institute
(ETSI)/Experiential Networked Intelligence (ENI), TMF with its
Autonomous Networks, have proposed intents for defining a set of
network operations to execute in a declarative manner.
More recently, the IRTF NMRG is working on the Intent-based
Networking - Concepts and Definitions document, [CLEMM]. This
document clarifies the concept of "Intent" and provides an overview
of the functionality that is associated with it. The goal is to
contribute towards a common and shared understanding of terms,
concepts, and functionality that can be used as the foundation to
guide further definition of associated research and engineering
problems and their solutions.
The present document, together with [CLEMM], aims to become the
foundation for future intent-related topic discussions regarding the
NMRG.
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The SDOs usually came up with their own way of specifying an intent,
and with their own understanding of what an intent is. Besides that,
each SDO defines a set of terms and level of abstraction, its
intended intent users, and the applications and usage scenarios.
However, most intent approaches proposed by SDOs share the same
following features:
o It must be declarative in nature, meaning that an intent user
specifies the goal on the network without specifying how to achieve
that goal.
o It must be vendor agnostic, in the sense that it abstracts the
network capabilities, or the network infrastructure from the intent
user, and it can be ported across different platforms.
o It must provide an easy-to-use interface, which simplifies the
intent users' interaction with the intent system through the usage
of familiar terminology or concepts.
It should be able to detect and resolve intent conflicts, which
include, for example, static (compile-time) conflicts and dynamic
(run-time) conflicts.
1.3. Scope
The focus of this document is on the definition of criteria enabling
to categorize intents from the stakeholders' viewpoint. Concepts and
definitions related to IBN are provided in [CLEMM].
This document mostly addresses intents in the context of network
intents, however other types of intents are not excluded, as
presented in section 4.4. and section 6.2. .
It is impossible to fully differentiate intents only by the common
characteristics followed by concepts, terms and intentions. This
document clarifies what an intent represents for different
stakeholders through a classification on various dimensions, such as
solutions, intent users, and intent types. This classification
ensures common understanding among all participants and is used to
determine the scope and priority of individual projects, proof-of-
concept (PoCs), research initiatives, or open source projects.
The scope of intent classification in this document includes
solutions, intent users and intent types, and the initial
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classification table is made according to this scope. The
methodology presented can be used to update the classification
tables by adding or removing different solutions, intent users, or
intent types to cater for future scenarios, applications or domains.
2. Acronyms
AI: Artificial Intelligence
CE: Customer Equipment
CFS: Customer Facing Service
CLI: Command Line Interface
DB: Database
DC: Data Center
ECA: Event-Condition-Action
GBP: Group-Based Policy
GPU: Graphics Processing Unit
IBN: Intent Based Network
NFV: Network Function Virtualization
O&M: Operations & Maintenance
ONF: Open Networking Foundation
ONOS: Open Network Operating System
PNF: Physical Network Function
QoE: Quality of Experience
RFS: Resource Facing Service
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SDO: Standards Development Organization
SD-WAN: Software-Defined Wide-Area Network
SLA: Service Level Agreement
SUPA: Simplified Use of Policy Abstractions
VM: Virtual Machine
VNF: Virtual Network Function
3. Definitions
A common and shared understanding of terms and definitions related
to IBN is provided in [CLEMM], as follows:
o Intent: A set of operational goals (that a network should meet)
and outcomes (that a network is supposed to deliver), defined
in a declarative manner without specifying how to achieve or
implement them.
o Intent-Based Network: A network that can be managed using
intent.
o Policy: A set of rules that governs the choices in behaviour of
a system.
o Intent User: A user that defines and issues the intent request
to the intent-based management system.
Other definitions relevant to this draft, such as intent scope,
intent network scope, intent abstraction, intent abstraction, and
intent lifecycle are available in section 5.
4. Abstract Intent Requirements
In order to understand the different intent requirements that would
drive intent classification, we first need to understand what intent
means for different intent users.
4.1. What is Intent?
The term Intent has become very widely used in the industry for
different purposes, sometimes it is not even in agreement with SDO
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shared principles mentioned in the Introduction section.[CLEMM] draft
brings clarification with relation to what an intent is and how it
differentiates from policies and services.
Different stakeholders have different perspective of the network and
therefore have different intent requirements. Their intent is
sometimes technical, non-technical, abstract or technology specific.
Therefore, it is important to start a discussion in the industry and
academia communities about what intent is for different solutions and
intent users. It is also imperative to try to propose some intent
categories/ classifications that could be understood by a wider
audience. This would help us define intent interfaces, domain-
specific languages, and models.
4.2. Intent Solutions and Intent Users
Intent types are defined by all aspects that are required to profile
different requirements to easily distinguish among them. However, in
order to facilitate a clustered classification, we can focus on two
aspects, the solution and intent user. They can be considered as the
main keys to classify intents, as we can easily group requirements by
solution and intent user.
On the one hand, different solutions and intent users have different
requirements, expectations and priorities for intent-based
networking. Therefore, intent users require different intent types,
depending on their context, since they participate in different use
cases. For instance, some intent users are more technical and require
intents that expose more technical information. Other intent users do
not have knowledge of the network infrastructure and require intents
that shield them from different networking concepts and technologies.
The following are the solutions and intent users that intent-based
networking needs to support:
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+--------------------+------------------------------------+
| Solutions | Intent Users |
+--------------------+------------------------------------+
| Carrier Networks | Network Operator |
| | Service Designers/App Developer |
| | Service Operators |
| | Customers/Subscribers |
+--------------------+------------------------------------+
| DC Networks | Cloud Administrator |
| | Underlay Network Administrator |
| | Application Developers |
| | Customer/Tenants |
+--------------------+------------------------------------+
| Enterprise Networks| Enterprise Administrator |
| | Application Developers |
| | End-Users |
+--------------------+------------------------------------+
Table 1 - Intent Solutions and Intent Users
These intent solutions and intent users represent a starting point
for the classification and are expendable through the methodology
presented in section 6.1. .
o For carrier networks scenario, for example, if a
customer/subscriber wants to watch high-definition video, then the
intent is to convert the video image to 1080p rate.
o For DC networks scenario, administrators have their own clear
network intent such as load balancing. For all traffic flows that
need NFV service chaining, restrict the maximum load of any VNF
node/container below 50% and the maximum load of any network link
below 70%.
o For enterprise networks scenario, when hosting a video conference
multiple remote accesses are required. An example of the intent
from the network administrator is: for any end-user of this
application, the arrival time of hologram objects of all the
remote tele-presenters should be synchronised within 50ms to reach
the destination viewer for each conversation session.
o
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4.3. Benefits of Intents for Different Stakeholders
Current network APIs and CLIs are too complex because they are highly
integrated with the low level concepts exposed by networks.
Customers, application developers and end-users must not be required
to set IP addresses, VLANs, subnets, ports, while operators may still
want to have more technical and network visibility. All stakeholders
would benefit from the simpler interfaces, like:
o Request gold VPN service between my sites A, B and C
o Provide CE redundancy for the customer sites
o Add access rules to the network service
Operators and administrators manually troubleshoot and fix their
networks and services. They instead want to:
o simplify and automate network operations
o simplify definitions of network services
o provide simple customer APIs for value added services (operators)
o be informed if the network or service is not behaving as requested
o enable automatic optimization and correction for selected
scenarios
o have systems that learn from historic information and behaviour
Currently, intent users cannot build their own services and policies
without becoming technical experts and performing manual maintenance
actions. They instead want to be able to:
o build their own network services with their own policies via
simple interfaces, without becoming networking experts
o have their network services up and running based on intent and
automation only, without any manual actions or maintenance
o
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4.4. Intent Types that need to be supported
Next to the intent solutions and intent users, another way to
categorize the intent is through the intent types. The following
intent types and subtypes need to be supported, in order to address
the requirements from different solutions and intent users:
o Customer service intent
o for customer self-service with SLA
o for service operator orders
o Network and underlay network service intent
o for service operator orders
o for intent driven network configuration, verification,
correction and optimization
o for intent created and provided by the underlay network
administrator
o Network and underlay network intent
o for network configuration
o for automated lifecycle management of network configurations
o for network resources (switches, routers, routing, policies,
underlay)
o Cloud management intent
o for DC configuration, VMs, DB servers, APP servers
o for communication between VMs
o Cloud resource management intent
o for cloud resource life-cycle management (policy driven self-
configuration and auto-scaling and recovery/optimization)
o Strategy intent
o for security, QoS, application policies, traffic steering, etc.
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o for configuring and monitoring policies, alarms generation for
non-compliance, auto-recovery
o for design models and policies for network and network service
design
o for design workflows, models and policies for operational task
intents
o Operational task intents
o for network migration
o for device replacements
o for network software upgrades
o for automating any other tasks that operators/administrator
often perform
It is important to mention there all of the previously mentioned
types and subtypes may affect other intents. For example, operational
task intent can modify many other intents. The task itself is short-
lived, but the modification of other intents has an impact on their
life-cycle, so those changes must continue to be continuously
monitored and self-corrected/self-optimized.
5. Functional Characteristics and Behaviour
Intent can be used to operate immediately on a target (much like
issuing a command), or whenever it is appropriate (e.g., in response
to an event). In either case, intent has a number of behaviours that
serve to further organize its purpose, as described by the following
subsections.
5.1. Abstracting Intent Operation
The modelling of intents can be abstracted using the following
three-tuple:
{Context, Capabilities, Constraints}
o Context grounds the intent, and determines if it is relevant or
not for the current situation. Thus, context selects intents based
on applicability.
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o Capabilities describe the functionality that the intent can
perform. Capabilities take different forms, depending on the
expressivity of the intent as well as the programming paradigm(s)
used.
o Constraints define any restrictions on the capabilities to be used
for that particular context.
Metadata can be attached via strategy templates to each of the
elements of the three-tuple, and may be used to describe how the
intent should be used and how it operates, as well as prescribe any
operational dependencies that must be taken into account.
Although different intent categories share the same abstracted intent
model, each category will have its own specific context, capabilities
and constraints.
5.2. Intent User Types
Expanding on the introduction in section 4.2. , intent user types
represent the intent users that define and issue the intent request.
Depending on the intent solutions, there are specific intent users.
Examples of intent users are customers, network operators, service
operators, enterprise administrators, cloud administrators, and
underlay network administrators, or application developers.
o Customers and end-users do not necessarily know the functional and
operational details of the network that they are using.
Furthermore, they lack skills to understand such details; in fact,
such knowledge is typically not relevant to their job. In
addition, the network may not expose these details to its intent
users. This class of intent users focuses on the applications that
they run, and uses services offered by the network. Hence, they
want to specify policies that provide consistent behaviour
according to their business needs. They do not have to worry about
how the intents are deployed onto the underlying network, and
especially, whether the intents need to be translated to different
forms to enable network elements to understand them.
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o Application developers work in a set of abstractions defined by
their application and programming environment(s). For example,
many application developers think in terms of objects (e.g., a
VPN). While this makes sense to the application developer, most
network devices do not have a VPN object per se; rather, the VPN
is formed through a set of configuration statements for that
device in concert with configuration statements for the other
devices that together make up the VPN. Hence, the view of
application developers matches the services provided by the
network, but may not directly correspond to other views of other
intent users.
o Network operators may have the knowledge of the underlying
network. However, they may not understand the details of the
applications and services of customers.
5.3. Intent Scope
Intents are used to manage the behaviour of the networks they are
applied to and all intents are applied within a specific scope, such
as:
o Connectivity scope, if the intent creates or modifies a
connection.
o Security/privacy scope, if the intent specifies the security
characteristics of the network, customers, or end-users.
o Application scope, when the intent specifies the applications to
be affected by the intent request.
o QoS scope, when the intent specifies the QoS characteristics of
the network.
These intent scopes are expendable through the methodology presented
in section 6.1. .
5.4. Intent Network Scope
Regardless on the intent user type, their intent request is affecting
the network, or network components, which are representing the intent
targets.
Thus, intent network scope, or policy target as known in the area of
declarative policy, can represent VNFs or PNFs, physical network
elements, campus networks, SD-WAN networks, radio access networks,
cloud edge, cloud core, branch, etc.
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5.5. Intent Abstraction
Intent can be classified by whether it is necessary to feedback
technical network information or non-technical information to the
intent user after the intent is executed. As well, intent abstraction
covers the level of technical details in the intent itself.
o For non-technical intent users, they do not care how the intent is
executed, or the details of the network. As a result, they do not
need to know the configuration information of the underlying
network. They only focus on whether the intent execution result
achieves the goal, and the execution effect such as the quality of
completion and the length of execution. In this scenario, we refer
to an abstraction without technical feedback.
o For administrators, such as network administrators, they perform
intents, such as allocating network resources, selecting
transmission paths, handling network failures, etc. They require
multiple feedback indicators for network resource conditions,
congestion conditions, fault conditions, etc. after execution. In
this case, we refer to an abstraction with technical feedback.
As per intent definition provided in [CLEMM], lower-level intents are
not considered to qualify as intents. However, we kept this
classification to identify any PoCs/Demos/Use Cases that still either
require or implement lower level of abstraction for intents.
5.6. Intent Life-cycle
Intents can be classified into transient and persistent intents:
o If the intent is transient, it has no life-cycle management. As
soon as the specified operation is successfully carried out, the
intent is finished, and can no longer affect the target object.
o If the intent is persistent, it has life-cycle management. Once
the intent is successfully activated and deployed, the system will
keep all relevant intents active until they are deactivated or
removed.
5.7. Autonomous Driving Levels
In different phases of the autonomous driving network [TMF-auto], the
intents are different. Depending on the Autonomous Network Level of
the overall solution, we may have different intent requirements and
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types. For example, at lower level the customer intent is
automatically converted to configuration policies only, while at the
higher levels the customer intent is covering the full life cycle, it
is converted to both configuration and monitoring policies and is
self-assured using AI.
A typical example of autonomous driving network level 0 to 5 are
listed as below.
o Level 0 - Traditional manual network: O&M personnel manually
control the network and obtain network alarms and logs. - No
intent
o Level 1 - Partially automated network: Automated scripts are used
to automate service provisioning, network deployment, and
maintenance. Shallow perception of network status and decision
making suggestions of machine; - No intent
o Level 2 - Automated network: Automation of most service
provisioning, network deployment, and maintenance of a
comprehensive perception of network status and local machine
decision making; - simple intent on service provisioning
o Level 3 - Self-optimization network: Deep awareness of network
status and automatic network control, meeting requirements of
intent users of the network. - Intent based on network status
cognition
o Level 4 - Partial autonomous network: In a limited environment,
people do not need to participate in decision-making and networks
can adjust itself. - Intent based on limited AI
o Level 5 - Autonomous network: In different network environments
and network conditions, the network can automatically adapt to and
adjust to meet people's intentions. - Intent based on AI
6. Intent Classification
This section proposes an intent classification approach that may help
to classify mainstream intent related demos/tools.
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The three classifications in this document have been proposed from
scratch, following the methodology presented, through three
iterations: one for carrier network intent solution, one for DC
intent solution, and one for enterprise intent solution. For each
intent solution, we identified the specific intent users and intent
types. Then, we further identified intent scope, network scope,
abstractions, and life-cycle requirements.
These classifications and the generated tables can be easily
extended. For example, for the DC intent solution, a new category is
identified, i.e. resource scope, and the classification table has
been extended accordingly.
In the future, as new scenarios, applications, and domains are
emerging, new classifications and taxonomies can be identified,
following the proposed methodology.
The intent classifications have been documented to the best of our
knowledge at this point in time. Additional classifications will most
probably see the light in the future.
The output of the intent classification is the intent taxonomy
introduced in the next sections.
Thus, this section first introduces the proposed intent
classification methodology, followed by consolidated intent taxonomy
for three intent solutions, and then by concrete examples of intent
classifications for three different intent solutions (e.g. carrier
network, data center, and enterprise) that were derived using the
proposed methodology and then can be filled in for PoCs, demos,
research projects or future drafts.
6.1. Intent Classification Methodology
This section describes the methodology used to derive the initial
classification proposed in the draft. The proposed methodology can be
used to create new intent classifications from scratch, by analysing
the solution knowledge. As well, the methodology can be used to
update existing classification tables by adding or removing different
solutions, intent users or intent types in order to cater for future
scenarios, applications or domains.
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+------------------------------------------+
|Solution Knowledge (requirements, |
|use cases, technologies, network, intent |
|users, intent requirements) |
+----------------+-------------------------+
| Input Rx=Read
| Ux=Update (Add/Remove)
+--------V--------+
|1.Identify Intent|
| Solution +------------+
| | |
+---------^-+-----+ |
R1 | | U1 |
+---------------+ U8 | | R2 +--v----------------+
|8.Identify New +---------+ | | +-----------> 2.Identify |
| Categories | R8 | | | | U2 | Intent |
| <-------- | | | | +---------+ User Types |
+--------^------+ | | | | | | +-------|-----------+
| | | | | | | |
| ++-+-v-v---+-v-+ |
+--------+------+ U7 | | R3 +------v------------+
|7.Identify +------> Intent +--------> 3.Identify |
| Life-cycle | R7 |Classification| U3 | Type |
| Requirements <------+ <--------+ of Intent |
+--------^------+ +^--^-+--^-+---+ +------|------------+
| || | | | | |
| || | | | | |
+--------+-----+ || | | | | R4 +-------v-----------+
|6.Identify | U6 || | | | +-----------> 4.Identify |
| Abstractions+---------| | | | U4 | Intent |
| <---------+ | | +-------------+ Scope |
+-------^------+ R6 | | +-------+-----------+
| | | |
| U5 | |R5 |
| +-------+-v--------+ |
| |5.Identify Network| |
+----------+ Scope <---------------+
+------------------+
Figure 1 - Intent Classification Methodology
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The intent classification workflow starts from the solution
knowledge, which can provide information on requirements, use cases,
technologies used, network properties, intent users that define and
issue the intent request, and requirements. The following, defines
the steps to classify an intent:
1. The information provided in the solution knowledge is given as
input for identifying the intent solution (e.g. carrier, enterprise,
and data center). Intent solutions are reviewed against the existing
classification and they can either be used if present or added if not
there or removed if not needed, from the classification. (R1-U1).
2. Identify the intent user types (e.g. customer, network operators,
service operators, etc.), review existing intent classification and
use the intent user type if present, add if it is not there or remove
it if not needed (R2-U2).
3. Identify the types of intent (e.g. network intent, customer
service intent) and then review existing classification and
use/add/remove the intent type (R3-U3).
4. Identify the intent scopes (e.g. connectivity, application) based
on the solution knowledge and then review existing classification and
use/add/remove the identified intent scope (R4-U4).
5. Identify the network scopes (e.g. campus, radio access) and then
review existing classification and either use it or add/remove the
identified network scope (R5-U5).
6. Identify the abstractions (e.g. technical, non-technical) and
then review existing classification and use/add/remove the
abstractions (R6-U6).
7. Identify the life-cycle requirements (e.g. persistent, transient)
and then review existing classification and use/add/remove the life-
cycle requirements (R7-U7).
8. Identify any new categories and use/add the newly identified
categories. New categories can be identified as new domains or
applications are emerging, or new areas of concern (e.g. privacy,
compliance) might arise, which are not listed in the current
methodology.
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6.2. Intent Taxonomy
The following taxonomy describes the various intent solutions, intent
user types, intent types, intent scopes, network scopes, abstractions
and life-cycle and represents the output of the intent classification
tables for each of the solutions addressed (i.e. carrier, data
center, and enterprise solutions).
The intent scope categories in Figure 2 are shared among the carrier,
DC, and enterprise solutions. The abbreviations (Cx) in sections
6.3.2. 6.4.2. are introduced with the scope of fitting as column
title in the following tables.
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+--------------------------------+
+-->|Carrier Enterprise Data Center|
| +--------------------------------+
| +--------------------------------+
| |Customer/Subscriber/End-User |
+----------+ | |Network or Service Operator |
+>+Solutions +--+ |Application Developer |
| +----------+ +->|Enterprise Administrator |
| | |Cloud Administrator |
| +----------+ | |Underlay Network Administrator |
+>+Intent +---+ +--------------------------------+
| |User | +--------------------------------+
| |Types | |Customer Service Intent |
| +----------+ |Strategy Intent |
| +----------+ |Network Service Intent |
+>+Intent +----->|Underlay Network Service Intent |
+------+ | |Type | |Network Intent |
|Intent+-+ +----------+ |Underlay Network Intent |
+------+ | |Operational Task Intent |
| +----------+ |Cloud Management Intent |
+>+Intent +---+ |Cloud Resource Management Intent|
| |Scope | | +--------------------------------+
| +----------+ | +--------------------------------+
| +->|Connectivity Application QoS |
| +----------+ |Security/Privacy Storage Compute|
+>+Network +---+ +--------------------------------+
| |Scope | | +--------------------------------+
| +----------+ | |Radio Access Branch |
| +->|Transport Access SD-WAN |
| +----------+ |Transport Aggr. VNF PNF |
+>+Abstrac +----+ |Transport Core Physical |
| |tion | | |Cloud Edge Logical |
| +----------+ | |Cloud Core Campus |
| +----------+ | +--------------------------------+
+>+Life | | +--------------------------------+
|cycle +--+ +>|Technical Non-Technical |
+----------+ | +--------------------------------+
| +--------------------------------+
+-->|Persistent Transient |
+--------------------------------+
Figure 2 - Intent Taxonomy
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6.3. Intent Classification for Carrier Solution
6.3.1. Intent Users and Intent Types
This section addresses step 1, 2, and 3 from Figure 1 and the
following table describes the intent users in carrier solutions and
intent types with their descriptions for different intent users.
+-------------+-------------+---------------------------------------+
| Intent User | Intent Type | Intent Type Description |
+-------------------------------------------------------------------+
| Customer/ |Customer |Customer self-service with SLA and |
| Subscriber |Service |value added service |
| |Intent |Example: Always maintain high quality |
| | |of service and high bandwidth for gold |
| | |level subscribers. |
| | |Operational statement: Measure the |
| | |network congestion status, give |
| | |different adaptive parameters to |
| | |stations of different priority, thus in|
| | |heavy load situation, make the |
| | |bandwidth of the high-priority |
| | |customers guaranteed. |
| | |At the same time ensure the overall |
| | |utilization of system, improve |
| | |the overall throughput of the system. |
| +-----------------------------------------------------+
| |Strategy |Customer designs models and policy |
| |Intent |intents to be used by customer service |
| | |intents. |
| | |Example: Request reliable service |
| | |during peak traffic periods for apps |
| | |of type video. |
+-------------------------------------------------------------------+
|Network |Network |Service provided by network service |
|Operator |Service |operator to the customer |
| |Intent |(e.g. the service operator) |
| | |Example: Request network service with |
| | |delay guarantee for access customer A. |
| +-------------+---------------------------------------+
| |Network |Network operator requests network-wide |
| |Intent |(service underlay or other network-wide|
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| | |configuration) or network resource |
| | |configurations (switches, routers, |
| | |routing, policies). Includes |
| | |connectivity, routing, QoS, security, |
| | |application policies, traffic steering |
| | |policies, configuration policies, |
| | |monitoring policies, alarm generation |
| | |for non-compliance, auto-recovery, etc.|
| | |Example: Request high priority queueing|
| | |for traffic of class A. |
| +-----------------------------------------------------+
| |Operational |Network operator requests execution of |
| |Task |any automated task other than network |
| |Intent |service intent and network intent |
| | |(e.g. network migration, server |
| | |replacements, device replacements, |
| | |network software upgrades). |
| | |Example: Request migration of all |
| | |services in network N to backup path P.|
| +-----------------------------------------------------+
| |Strategy |Network operator designs models, policy|
| |Intent |intents and workflows to be used by |
| | |network service Intents, network |
| | |intents and operational task intents. |
| | |Workflows can automate any tasks that |
| | |network operator often performed in |
| | |addition to network service intents and|
| | |network intents |
| | |Example: Ensure the load on any link in|
| | |the network is not higher than 50%. |
+-------------+-------------+---------------------------------------+
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+-------------+-------------+---------------------------------------+
| Service | Customer | Service operator's customer orders, |
| Operator | Service | customer service / SLA |
| | Intent | Example: Provide service S with |
| | | guaranteed bandwidth for customer A. |
| +-----------------------------------------------------+
| | Network | Service operator's network orders / |
| | Service | network SLA |
| | Intent | Example: Provide network guarantees in|
| | | terms of security, low latency and |
| | | high bandwidth |
| +-----------------------------------------------------+
| | Operational | Service operator requests execution of|
| | Task | any automated task other than |
| | Intent | customer service intent and network |
| | | service intent |
| | | Example: Update service operator |
| | | portal platforms and their software |
| | | regularly. Move services from network |
| | | operator 1 to network operator 2. |
| +-----------------------------------------------------+
| | Strategy | Service operator designs models, |
| | Intent | policy intents and workflows to be |
| | | used by customer service intents, |
| | | network service intents and |
| | | operational task intents. Workflows |
| | | can automate any tasks that service |
| | | operator often performed in addition |
| | | to network service intents and network|
| | | intents. |
| | | Example: Request network service |
| | | guarantee to avoid network congestion |
| | | during special periods |
| | | such as black Friday, and Christmas. |
+-------------+-------------+---------------------------------------+
| Application | Customer | Customer service intent API provided |
| Developer | Service | to the application developers |
| | Intent | Example: API to request network to |
| | | watch HD video 4K/8K. |
| +-----------------------------------------------------+
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| | Network | Network service intent API provided to|
| | Service | the application developers |
| | Intent | Example:API to request network service|
| | | , monitoring and traffic grooming. |
| +-----------------------------------------------------+
| | Network | Network intent API provided to the |
| | Intent | application developers |
| | | Example: API to request network |
| | | resources configuration. |
| +-----------------------------------------------------+
| | Operational | Operational task intent API provided |
| | Task | to the application developers. This is|
| | Intent | for the trusted internal operator / |
| | | service providers / customer DevOps |
| | | Example: API to request server |
| | | migrations. |
| +-----------------------------------------------------+
| | Strategy | Application developer designs models, |
| | Intent | policy and workflows to be used by |
| | | customer service intents, network |
| | | service intents and operational |
| | | task intents. This is for the trusted |
| | | internal operator/service provider/ |
| | | customer DevOps |
| | | Example: API to design network load |
| | | balancing strategies during peak times|
+-------------+-------------+---------------------------------------+
Table 2 - Intent Classification for Carrier Solution
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6.3.2. Intent Categories
This subsection addresses step 4 to 7 from Figure 1, and the
following are the proposed categories:
o Intent Scope: C1=Connectivity, C2=Security/Privacy,
C3=Application, C4=QoS
o Network Scope:
o Network Domain: C1=Radio Access, C2=Transport Access,
C3=Transport Aggregation, C4=Transport Core, C5=Cloud Edge,
C6=Cloud Core)
o Network Function (NF) Scope: C1=VNFs, C2=PNFs
o Abstraction (ABS): C1=Technical (with technical feedback),
C2=Non-technical (without technical feedback) see section 5.2. .
o Life-cycle (L-C): C1=Persistent (full life-cycle), C2=Transient
(short lived)
6.3.3. Intent Classification Example
This section depicts an example on how the methodology described in
section 6.1. can be used in order to classify intents introduced in
the 'A Multi-Level Approach to IBN' PoC demonstration [POC-IBN]. This
PoC is led by academics carrying research in the area of SDN/NFV and
the specific problem they are addressing is to apply the intent
concept at different levels that correspond to different
stakeholders. For this research work, they considered two types of
intents: slice intents and service chain intents.
In this PoC [POC-IBN], a slice intent expresses a request for a
network slice with two types of components: a set of top layer
virtual functions, and a set of virtual switches and/or routers of
L2/L3 VNFs. A service chain intent expressed a request for a service
operated through a chain of service components running in L4-L7
virtual functions.
Following the intent classification methodology described step-by-
step in section 6.1. , the following can be derived:
1. The intent solution for both intents is carrier network.
2. The intent user type is network operator for the slice intent, and
service operator for the service chain intent.
3. The type of intent, is a network service intent for the slice
intent, and a customer service intent for the service chain intent.
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4. The intent scopes are connectivity and application.
5. The network scope is VNF, cloud edge, and cloud core.
6. The abstractions are with technical feedback for the slice intent,
and without technical feedback for the service chain intent
7. The life-cycle is persistent.
The following table shows how to represent this information in a
tabular form. The 'X' in the table refers to the slice intent, and
the 'Y' in the table refers to the service chain intent.
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+---------+---------+-----------+-----+-----------------+-----+-----+
| Intent | Intent | Intent | NF | Network | ABS |L-C |
| User | Type | Scope |Scope| Scope | | |
| | +-----------+-----+-----------------+-----+-----+
| | |C1|C2|C3|C4|C1|C2|C1|C2|C3|C4|C5|C6|C1|C2|C1|C2|
+---------+---------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
|Customer |Customer | | | | | | | | | | | | | | | | |
|/ Sub- |Service | | | | | | | | | | | | | | | | |
| scriber |Intent | | | | | | | | | | | | | | | | |
| +---------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| |Strategy | | | | | | | | | | | | | | | | |
| |Intent | | | | | | | | | | | | | | | | |
+---------+---------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
|Network |Network |X | |X | |X | | | | | |X | |X | |X | |
|Operator |Service | | | | | | | | | | | | | | | | |
| |Intent | | | | | | | | | | | | | | | | |
| +---------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| |Network | | | | | | | | | | | | | | | | |
| |Intent | | | | | | | | | | | | | | | | |
| +---------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| |Operatio-| | | | | | | | | | | | | | | | |
| |nal Task | | | | | | | | | | | | | | | | |
| |Intent | | | | | | | | | | | | | | | | |
| +---------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| |Strategy | | | | | | | | | | | | | | | | |
| |Intent | | | | | | | | | | | | | | | | |
+---------+---------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
|Service |Customer |Y | |Y | |Y | | | | | |Y |Y | |Y |Y | |
|Operator |Service | | | | | | | | | | | | | | | | |
| |Intent | | | | | | | | | | | | | | | | |
| +---------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| |Network | | | | | | | | | | | | | | | | |
| |Service | | | | | | | | | | | | | | | | |
| |Intent | | | | | | | | | | | | | | | | |
| +---------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| |Op Task | | | | | | | | | | | | | | | | |
| |Intent | | | | | | | | | | | | | | | | |
| +---------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| |Strategy | | | | | | | | | | | | | | | | |
| |Intent | | | | | | | | | | | | | | | | |
+---------+---------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
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|App |Customer | | | | | | | | | | | | | | | | |
|Developer|Intent | | | | | | | | | | | | | | | | |
| +---------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| |Network | | | | | | | | | | | | | | | | |
| |Service | | | | | | | | | | | | | | | | |
| |Intent | | | | | | | | | | | | | | | | |
| +---------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| |Network | | | | | | | | | | | | | | | | |
| |Intent | | | | | | | | | | | | | | | | |
| +---------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| |Op Task | | | | | | | | | | | | | | | | |
| |Intent | | | | | | | | | | | | | | | | |
| +---------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| |Strategy | | | | | | | | | | | | | | | | |
| |Intent | | | | | | | | | | | | | | | | |
+---------+---------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
Table 3 - Intent Classification Example for Carrier Solution
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6.4. Intent Classification for Data Center Network Solutions
6.4.1. Intent Users and Intent Types
The following table describes the intent users in DC network
solutions and intent types with their descriptions for different
intent users.
+---------------+-------------+-------------------------------------+
| Intent User | Intent Type | Intent Type Description |
+-------------------------------------------------------------------+
| Customer / | Customer | Customer self-service via tenant |
| Tenants | Service | portal. |
| | | Example: Request GPU computing and |
| | | storage resources to meet 10k video |
| | | surveillance services. |
| +---------------------------------------------------+
| | Strategy | This includes models and policy |
| | Intent | intents designed by customers/ |
| | | tenants to be reused later during |
| | | instantiation. |
| | | Example: Request dynamic computing |
| | | and storage resources of the service|
| | | in special and daily times. |
| | | |
+-------------------------------------------------------------------+
| | Cloud | Configuration of VMs, DB Servers, |
| Cloud | Management | app servers, connectivity, |
| Administrator | Intent | communication between VMs. |
| | | Example: Request connectivity |
| | | between VMs A,B,and C in network N1.|
| +---------------------------------------------------+
| | Cloud | Policy-driven self-configuration and|
| | Resource | and recovery / optimization |
| | Management | Example: Request automatic life |
| | Intent |-cycle management of VM cloud |
| | | resources. |
| +---------------------------------------------------+
| | Operational | Cloud administrator requests |
| | Task Intent | execution of any automated task |
| | | other than cloud management |
| | | intents and cloud resource |
| | | management intents. |
| | | Example: Request upgrade operating |
| | | system to version X on all VMs |
| | | in network N1. |
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| | |Operational statement: an intent to |
| | |update a system might reconfigure the|
| | |system topology (connect to a service|
| | |and to peers), exchange data (update |
| | |the content), and uphold a certain |
| | |QoE level (allocate sufficient |
| | |network resources). The network, |
| | |thus, carries out the necessary |
| | |configuration to best serve such an |
| | |intent; e.g. setting up direct |
| | |connections between terminals, and |
| | |allocating fair shares of router |
| | |queues considering other network |
| | |services.
| +---------------------------------------------------+
| | Strategy | Cloud administrator designs models, |
| | Intent | policy intents and workflows to be |
| | | used by other intents. Automate any |
| | | tasks that administrator often |
| | | performs, in addition to life-cycle |
| | | of cloud management intents and |
| | | cloud management resource intents. |
| | | Example: In case of emergency, |
| | | automatically migrate all cloud |
| | | resources to DC2. |
+---------------+---------------------------------------------------+
| Underlay | Underlay | Service created and provided by |
| Network | Network | the underlay network administrator. |
| Administrator | Service | Example: Request underlay service |
| | Intent | between DC1 and DC2 with |
| | | bandwidth B. |
| +---------------------------------------------------+
| | Underlay | Underlay network administrator |
| | Network | requests some DCN-wide underlay |
| | Intent | network configuration or network |
| | | resource configurations. |
| | | Example: Establish and allocate |
| | | DHCP address pool. |
| +---------------------------------------------------+
| | Operational | Underlay network administrator |
| | Task Intent | requests execution of the any |
| | | automated task other than underlay |
| | | network service and resource |
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| | | intent. |
| | | Example: Request automatic rapid |
| | | detection of device failures and |
| | | pre-alarm correlation. |
| +---------------------------------------------------+
| | Strategy | Underlay network administrator |
| | Intent | designs models, policy intents & |
| | | workflows to be used by other |
| | | intents. Automate any tasks that |
| | | administrator often performs. |
| | | Example: For all traffic flows |
| | | that need NFV service chaining, |
| | | restrict the maximum load of any |
| | | VNF node/container below 50% and |
| | | the maximum load of any network |
| | | link below 70%. |
+-------------------------------------------------------------------+
| | Cloud | Cloud management intent API |
| | Management | provided to the application |
| | Intent | developers. |
| | | Example: API to request |
| | | configuration of VMs, or DB Servers.|
| Application +---------------------------------------------------+
| Developer | Cloud | Cloud resource management intent |
| | Resource | API provided to the application |
| | Management | developers. |
| | Intent | Example: API to request automatic |
| | | life-cycle management of cloud |
| | | resources. |
| +---------------------------------------------------+
| | Underlay | Underlay network service API |
| | Network | provided to the application |
| | Service | developers. |
| | Intent | Example: API to request real-time |
| | | monitoring of device condition. |
| +---------------------------------------------------+
| | Underlay | Underlay network resource API |
| | Network | provided to the application |
| | Intent | developers. |
| | | Example: API to request dynamic |
| | | management of IPv4 address pool |
| | | resources. |
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| | | |
| +---------------------------------------------------+
| | Operational | Operational task intent API |
| | Task Intent | provided to the trusted |
| | | application developer (internal |
| | | DevOps). |
| | | Example: API to request automatic |
| | | rapid detection of device failures |
| | | and pre-alarm correlation |
| | | |
| +---------------------------------------------------+
| | Strategy | Application developer designs |
| | Intent | models, policy intents and |
| | | building blocks to be used by |
| | | other intents. This is for the |
| | | trusted internal DCN DevOps. |
| | | Example: API to request load |
| | | balancing thresholds. |
+---------------+-------------+-------------------------------------+
Table 4 - Intent Classification for Data Center Network Solutions
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6.4.2. Intent Categories
The following are the proposed categories:
o Intent Scope: C1=Connectivity, C2=Security/Privacy,
C3=Application, C4=QoS C5=Storage C6=Compute
o Network Scope
o Network Domain: DC Network
o DCN Network (DCN Net) Scope: C1=Logical, C2=Physical
o DCN Resource (DCN Res) Scope: C1=Virtual, C2=Physical
o Abstraction (ABS): C1=Technical (with technical feedback),
C2=Non-technical (without technical feedback), see section 5.2.
o Life-cycle (L-C): C1=Persistent (full life-cycle), C2=Transient
(short lived)
6.4.3. Intent Classification Example
This section depicts an example on how the methodology described in
section 6.1. can be used by the research community to classify
intents. As mentioned in 6.3.3. a successful use of the
classification proposed in this draft is introduced in the 'A Multi-
Level Approach to IBN' PoC demonstration [POC-IBN]. The PoC is led by
academics carrying research in the area of SDN/NFV and the specific
problem they are addressing is to apply the intent concept at
different levels that correspond to different stakeholders.
For their research work, they considered two types of intents: slice
intents and service chain intents. For the data center solution, only
the slice intent is relevant.
As already mentioned in section 6.3.3. , a slice intent expresses a
request for a network slice with two types of components: a set of
top layer virtual functions, and a set of virtual switches and/or
routers of L2/L3 VNFs.
Following the intent classification methodology described step-by-
step in section 6.1. , we identify the following:
1. The intent solution is for the data center.
2. The intent user type is the cloud administrator for the slice
intent and service chain intent.
3. The type of intent, is a cloud management intent, for the slice
intent.
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4. The intent scopes are connectivity and application.
5. The network scope is logical, and the resource scope is virtual.
6. The abstractions are with technical feedback for the slice intent.
7. The life-cycle is persistent.
The following table shows how to represent this information in a
tabular form, where the 'X' in the table refers to the slice intent.
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+---------+-------------+-----------------+-----+-----+-----+-----+
|Intent | Intent | Intent | DCN | DCN | ABS | L-C |
|User | Type | Scope | Res | Net | | |
| | +-----------------+-----+-----+-----+-----+
| | |C1|C2|C3|C4|C5|C6|C1|C2|C1|C2|C1|C2|C1|C2|
+---------+-------------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
|Customer | Customer | | | | | | | | | | | | | | |
|/Tenants | Service | | | | | | | | | | | | | | |
| | Intent | | | | | | | | | | | | | | |
| +-------------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| | Strategy | | | | | | | | | | | | | | |
| | Intent | | | | | | | | | | | | | | |
+---------+-------------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| Cloud | Cloud | | | | | | | | | | | | | | |
| Admin | Management |X | |X | | | |X | |X | |X | |X | |
| | Intent | | | | | | | | | | | | | | |
| +-------------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| | Cloud | | | | | | | | | | | | | | |
| | Resource | | | | | | | | | | | | | | |
| | Management | | | | | | | | | | | | | | |
| | Intent | | | | | | | | | | | | | | |
| +-------------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| | Operational | | | | | | | | | | | | | | |
| | Task Intent | | | | | | | | | | | | | | |
| +-------------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| | Strategy | | | | | | | | | | | | | | |
| | Intent | | | | | | | | | | | | | | |
+---------+-------------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
|Underlay | Underlay | | | | | | | | | | | | | | |
|Network | Network | | | | | | | | | | | | | | |
|Admin | Intent | | | | | | | | | | | | | | |
| +-------------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| | Underlay | | | | | | | | | | | | | | |
| | Network | | | | | | | | | | | | | | |
| | Resource | | | | | | | | | | | | | | |
| | Intent | | | | | | | | | | | | | | |
| +-------------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| | Operational | | | | | | | | | | | | | | |
| | Task Intent | | | | | | | | | | | | | | |
| +-------------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| | Strategy | | | | | | | | | | | | | | |
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| | Intent | | | | | | | | | | | | | | |
+---------+-------------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
|App | Cloud | | | | | | | | | | | | | | |
|Developer| Management | | | | | | | | | | | | | | |
| | Intent | | | | | | | | | | | | | | |
| +-------------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| | Cloud | | | | | | | | | | | | | | |
| | Resource | | | | | | | | | | | | | | |
| | Management | | | | | | | | | | | | | | |
| | Intent | | | | | | | | | | | | | | |
| +-------------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| | Underlay | | | | | | | | | | | | | | |
| | Network | | | | | | | | | | | | | | |
| | Intent | | | | | | | | | | | | | | |
| +-------------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| | Underlay | | | | | | | | | | | | | | |
| | Network | | | | | | | | | | | | | | |
| | Resource | | | | | | | | | | | | | | |
| | Intent | | | | | | | | | | | | | | |
| +-------------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| | Operational | | | | | | | | | | | | | | |
| | Task Intent | | | | | | | | | | | | | | |
| +-------------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| | Strategy | | | | | | | | | | | | | | |
| | Intent | | | | | | | | | | | | | | |
+---------+-------------+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
Table 5 - Intent Classification Example for Data Center Network
Solutions
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6.5. Intent Classification for Enterprise Solution
6.5.1. Intent Users and Intent Types
The following table describes the intent users in enterprise
solutions and their intent types.
+--------------+-------------+-------------------------------------+
| Intent User | Intent Type | Intent Type Description |
+--------------+---------------------------------------------------+
| End-User | Customer | Enterprise end-user self-service or |
| | Service | applications, enterprise may have |
| | Intent | multiple types of end-users. |
| | | Example: Request access to VPN |
| | | service. |
| | | Request video conference between |
| | | end-user A and B. |
| +---------------------------------------------------+
| | Strategy | This includes models and policy |
| | Intent | intents designed by end-users to be |
| | | used by end-user intents and their |
| | | applications. |
| | | Example: Create a video conference |
| | | type for a weekly meeting. |
+------------------------------------------------------------------+
|Enterprise | Network | Service provided by the |
|Administrator | Service | administrator to the end-users |
|(internal or | Intent | and their applications. |
| MSP) | | Example: For any end-user of |
| | | application X, the arrival of |
| | | hologram objects of all the remote |
| | | tele-presenters should be |
| | | synchronised within 50ms to reach |
| | | the destination viewer for each |
| | | conversation session. |
| | | Create management VPN connectivity |
| | | for type of service A. |
| | | Operational statement: The job of |
| | | the network layer is to ensure that |
| | | the delay is between 50-70ms through|
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| | | the routing algorithm. At the same |
| | | time,the node resources need to meet|
| | | the bandwidth requirements of 4K |
| | | video conferences. |
+------------------------------------------------------------------+
| | Network | Administrator requires network wide |
| | Intent | configuration (e.g. underlay, |
| | | campus) or resource configuration |
| | | (switches, routers, policies). |
| | | Example: Configure switches in |
| | | campus network 1 to prioritise |
| | | traffic of type A. |
| | | Configure YouTube as business |
| | | non-relevant. |
| +---------------------------------------------------+
| | Operational | Administrator requests execution of |
| | Task Intent | any automated task other than |
| | | network service intents and network |
| | | intents. |
| | | Example: Request network security |
| | | automated tasks such as web |
| | | filtering and DDOS cloud protection.|
| +---------------------------------------------------+
| | Strategy | Administrator designs models, policy|
| | Intent | intents and workflows to be used by |
| | | other intents. Automate any tasks |
| | | that administrator often performs. |
| | | Example: In case of emergency, |
| | | automatically shift all traffic of |
| | | type A through network N. |
| | | |
+--------------+-------------+-------------------------------------+
| Application | End-User | End-user service / application |
| Developer | Intent | intent API provided to the |
| | | application developers. |
| | | Example: API for request to open a |
| | | VPN service. |
| +---------------------------------------------------+
| | Network | Network service API provided to |
| | Service | application developers. |
| | Intent | Example: API for request network |
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| | | bandwidth and latency for |
| | | hosting video conference. |
| +---------------------------------------------------+
| | Network | Network API provided to application |
| | Intent | developers. |
| | | Example: API for request of network |
| | | devices configuration. |
| +---------------------------------------------------+
| | Operational | Operational task intent API provided|
| | Task Intent | to the trusted application developer|
| | | (internal DevOps). |
| | | Example: API for requesting |
| | | automatic monitoring and |
| | | interception for network security |
| +---------------------------------------------------+
| | Strategy | Application developer designs |
| | Intent | models, policy intents and building |
| | | blocks to be used by other intents. |
| | | This is for the trusted internal |
| | | DevOps. |
| | | Example: API for strategy intent in |
| | | case of emergencies. |
| | | |
+--------------+-------------+-------------------------------------+
Table 6 - Intent Classification for Enterprise Solution
6.5.2. Intent Categories
The following are the proposed categories:
o Intent Scope: C1=Connectivity, C2=Security/Privacy,
C3=Application, C4=QoS
o Network (Net) Scope: C1=Campus, C2=Branch, C3=SD-WAN
o Abstraction (ABS): C1=Technical (with technical feedback),
C2=Non-technical (without technical feedback), see section 5.2.
o Life-cycle (L-C): C1=Persistent (full life-cycle), C2=Transient
(short lived)
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The following is the intent classification table example for
enterprise solutions.
+---------------+-------------+-----------+--------+-----+-----+
| Intent User | Intent Type | Intent | Net | ABS | L-C |
| | | Scope | | | |
| | +-----------+--------+-----+-----+
| | |C1|C2|C3|C4|C1|C2|C3|C1|C2|C1|C2|
+---------------+-------------+--+--+--+--+--+--+--+--+--+--+--+
| End-User | Customer | | | | | | | | | | | |
| | Service | | | | | | | | | | | |
| | Intent | | | | | | | | | | | |
| +-------------+--+--+--+--+--+--+--+--+--+--+--+
| | Strategy | | | | | | | | | | | |
| | Intent | | | | | | | | | | | |
+---------------+-------------+--+--+--+--+--+--+--+--+--+--+--+
| Enterprise | Network | | | | | | | | | | | |
| Administrator | Service | | | | | | | | | | | |
| | Intent | | | | | | | | | | | |
| +-------------+--+--+--+--+--+--+--+--+--+--+--+
| | Network | | | | | | | | | | | |
| | Intent | | | | | | | | | | | |
| +-------------+--+--+--+--+--+--+--+--+--+--+--+
| | Operational | | | | | | | | | | | |
| | Task | | | | | | | | | | | |
| | Intent | | | | | | | | | | | |
| +-------------+--+--+--+--+--+--+--+--+--+--+--+
| | Strategy | | | | | | | | | | | |
| | Intent | | | | | | | | | | | |
+---------------+-------------+--+--+--+--+--+--+--+--+--+--+--+
| Application | End-User | | | | | | | | | | | |
| Developer | Intent | | | | | | | | | | | |
| +-------------+--+--+--+--+--+--+--+--+--+--+--+
| | Network | | | | | | | | | | | |
| | Service | | | | | | | | | | | |
| | Intent | | | | | | | | | | | |
| +-------------+--+--+--+--+--+--+--+--+--+--+--+
| | Network | | | | | | | | | | | |
| | Intent | | | | | | | | | | | |
| +-------------+--+--+--+--+--+--+--+--+--+--+--+
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| | Operational | | | | | | | | | | | |
| | Task | | | | | | | | | | | |
| | Intent | | | | | | | | | | | |
| +-------------+--+--+--+--+--+--+--+--+--+--+--+
| | Strategy | | | | | | | | | | | |
| | Intent | | | | | | | | | | | |
+---------------+-------------+--+--+--+--+--+--+--+--+--+--+--+
Table 7 - Intent Categories for Enterprise Solution
7. Conclusions
This document is aligned with the RG objectives and supports
investigations into intent-based networking by proposing an intent
categorization methodology and taxonomy. It brings clarification on
what an intent represents for different stakeholders through the
proposal of an Intent Classification approach, ensuring that a
common understanding among all the participants exists. This,
together with the proposed intent taxonomy provides a solid
foundation for future intent-related topic discussions within NMRG.
The benefits of this intent classification draft in the research
community have been demonstrated through a PoC implementation [POC-
IBN] in which the draft's concepts at different levels corresponding
to different stakeholders have been applied to.
8. Security Considerations
This document identifies the security and privacy as categories of
the intent scope. The intents could be solely security intents and
privacy intents or security can be embedded in the intents that
include also connectivity, application, and QoS scope.
Security and privacy scope, is when the intent specifies the security
characteristics of the network, customers, or end-users, and privacy
for customers and end-users.
More details of these security intents would be described in future
documents that specify architecture, functionality, user intents and
models. As well, an analysis of the security considerations of the
overall intent-based system is provided in section 10 of [CLEMM].
9. IANA Considerations
This document has no actions for IANA.
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10. Contributors
The following people all contributed to creating this document:
Contributed significant text:
Xueyuan Sun, China Telecom
Will (Shucheng) Liu, Huawei
Contributed text in early drafts:
Ying Chen, China Unicom
John Strassner, Huawei
Weiping Xu, Huawei
Richard Meade, Huawei
11. Acknowledgments
This document has benefited from reviews, suggestions, comments and
proposed text provided by the following members, listed in
alphabetical order: Mehdi Bezahaf, Brian E Carpenter, Laurent
Ciavaglia, Benoit Claise, Alexander Clemm, Yehia Elkhatib, Jerome
Francois, Pedro Andres Aranda Gutierrez, Daniel King, Branislav
Meandzija, Bob Natale, Juergen Schoenwaelder, Xiaolin Song, Jeff
Tantsura.
We thank to Barbara Martini, Walter Cerroni, Molka Gharbaoui, Davide
Borsatti, for contributing with their 'A multi-level approach to
IBN' PoC demonstration a first attempt to adopt the intent
classification methodology.
12. Informative References
[Bezahaf21] Bezahaf, M., Davies, E., Rotsos, C. and Race, N., "To All
Intents and Purposes: Towards Flexible Intent Expression,"
2021 IEEE 7th International Conference on Network
Softwarization (NetSoft), 2021.
[Bezhaf19] Bezahaf, M., Hernandez, MP, Bardwell, L., Davies, E.,
Broadbent, M.,King, D. and Hutchison, D. , "Self-Generated
Intent-Based System," 2019 10th International Conference on
Networks of the Future (NoF), 2019.
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[Jacobs18] Jacobs, A.S., Pfitscher,R.J., Ferreira, R.A., and
Granville, L.Z., "Refining Network Intents for Self-Driving
Networks", Proceedings of the Afternoon Workshop on Self-
Driving Networks (SelfDN 2018), 2018.
[Banerjee21] Banerjee,A., Mwanje. S. and Carle, G., "Contradiction
Management in Intent-driven Cognitive Autonomous RAN",
2021.
[Tian19] Tian, B., Zhang, X., Zhai, E., Liu, H. H., Ye, Q., Wang, C.,
and Zhao, B. Y., "Safely and automatically updating in-
network ACL configurations with intent language", SIGCOMM
'19, 2019.
[Leivadeas21] Leivadeas, A. and Falkner, M., "VNF Placement Problem:
A Multi-Tenant Intent-Based Networking Approach," 24th
Conference on Innovation in Clouds, Internet and Networks
and Workshops (ICIN), 2021.
[Davoli21] Davoli, G., "Programmability and Management of Software-
defined Network Infrastructures", 2021.
[Padovan20] Padovan, S., "Design and Implementation of a Blockchain
Intent Management System", 2020.
[Mehmood21] Mehmood, K., Kralevska, K., and Palma, D., "Intent-driven
Autonomous Network and Service Management in Future
Networks: A Structured Literature Review", 2021.
[Szilagyi21] Szilagyi, P., "I2BN: Intelligent Intent Based Networks",
Journal of ICT Standardization, 2021.
[POC-IBN] Barbara Martini, Walter Cerroni, Molka Gharbaoui, Davide
Borsatti, "A multi-level approach to IBN", July 2020,
https://www.ietf.org/proceedings/108/slides/slides-108-
nmrg-ietf-108-hackathon-report-a-multi-level-approach-to-
ibn-02
[IFIP-NSM] IFIP - Network and Service Management Taxonomy,
https://www.simpleweb.org/ifip/taxonomy.html
[ONF] ONF, "Intent Definition Principles", 2017,
<https://www.opennetworking.org/images/stories/downloads/
sdn-resources/technical-reports/TR-
523_Intent_Definition_Principles.pdf>.
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[ONOS] ONOS, "ONOS Intent Framework", 2017,
<https://wiki.onosproject.org/display/ONOS/Intent+Framework
/>.
[CLEMM] A. Clemm, L. Ciavaglia, L. Granville, J. Tantsura, "Intent-
Based Networking - Concepts and Overview", Work in
Progress, draft-irtf-nmrg-ibn-concepts-definitions-05,
February 2021, https://tools.ietf.org/html/draft-irtf-nmrg-
ibn-concepts-definitions-05
[TMF-auto] Aaron Richard Earl Boasman-Patel,et, A whitepaper of
Autonomous Networks: Empowering Digital Transformation For
the Telecoms Industry, inform.tmforum.org, 15 May, 2019.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC7575] Behringer, M., Pritikin, M., Bjarnason, S., Clemm, A.,
Carpenter, B., Jiang, S., and L. Ciavaglia, "Autonomic
Networking: Definitions and Design Goals", RFC 7575, June
2015.
[RFC8328] Liu, W., Xie, C., Strassner, J., Karagiannis, G., Klyus,
M., Bi, J., Cheng, Y., and D. Zhang, "Policy-Based
Management Framework for the Simplified Use of Policy
Abstractions (SUPA)", March 2018.
[RFC3198] Westerinen, A., Schnizlein, J., Strassner, J.,
Scherling, M., Quinn, B., Herzog, S., Huynh, A., Carlson,
M., Perry, J., Waldbusser, S., "Terminology for Intent-
driven Management", RFC 3198, November 2001.
[RFC6020] Bjorlund, M., "YANG - A Data Modelling Language for Network
Configuration Protocol (NETCONF)", RFC 6020, October 2010.
[RFC7285] R. Alimi, R. Penno, Y. Yang, S. Kiesel, S. Previdi, W.
Roome, S. Shalunov, R. Woundy "Application-Layer Traffic
Optimization (ALTO) Protocol", September 2014.
[ANIMA] Du, Z., "ANIMA Intent Policy and Format", 2017,
<https://datatracker.ietf.org/doc/draft-du-anima-an-
intent/>.
[SUPA] Strassner, J., "Simplified Use of Policy Abstractions",
2017, <https://datatracker.ietf.org/doc/draft-ietf-supa-
generic-policy-info-model/?include_text=1>.
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[ANIMA-Prefix] Jiang, S., Du, Z., Carpenter, B., and Q. Sun,
"Autonomic IPv6 Edge Prefix Management in Large-scale
Networks", draft-ietf-anima-prefix-management-07 (work in
progress), December 2017.
Authors' Addresses
Chen Li
China Telecom
No.118 Xizhimennei street, Xicheng District
Beijing 100035
P.R. China
Email: lichen.bri@chinatelecom.cn
Olga Havel
Huawei Technologies
Ireland
Email: olga.havel@huawei.com
Adriana Olariu
Huawei Technologies
Ireland
Email: adriana.olariu@huawei.com
Pedro Martinez-Julia
NICT
Japan
Email: pedro@nict.go.jp
Jeferson Campos Nobre
Federal University of Rio Grande do Sul
Porto Alegre
Brazil
Email: jcnobre@inf.ufrgs.br
Diego R. Lopez
Telefonica I+D
Don Ramon de la Cruz, 82
Madrid 28006
Spain
Email: diego.r.lopez@telefonica.com
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