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Sustainability Insights
draft-almprs-sustainability-insights-00

Document Type Active Internet-Draft (individual)
Authors Per Andersson , Jan Lindblad , Snezana Mitrovic , Marisol Palmero , Esther Roure , Gonzalo Salgueiro
Last updated 2023-03-13
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draft-almprs-sustainability-insights-00
Network Working Group                                       P. Andersson
Internet-Draft                                               J. Lindblad
Intended status: Informational                               S. Mitrovic
Expires: 14 September 2023                                    M. Palmero
                                                                E. Roure
                                                            G. Salgueiro
                                                           Cisco Systems
                                                           13 March 2023

                        Sustainability Insights
                draft-almprs-sustainability-insights-00

Abstract

   This document motivates the collection and aggregation of
   sustainability environmental related metrics.  It describes the
   motivation and requirements to collect asset centric metrics
   including but not limited to power consumption and energy efficiency,
   circular economy properties, and more general metrics useful in
   environmental impact analysis.  It provides foundations for building
   an industry-wide, open-source framework for the reduction of
   greenhouse gas emissions, enabling measurement and optimization of
   the overall impact on the environment of networking devices, software
   applications, services, and solutions across the lifecycle journey.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at https://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on 14 September 2023.

Copyright Notice

   Copyright (c) 2023 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

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   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents (https://trustee.ietf.org/
   license-info) in effect on the date of publication of this document.
   Please review these documents carefully, as they describe your rights
   and restrictions with respect to this document.  Code Components
   extracted from this document must include Revised BSD License text as
   described in Section 4.e of the Trust Legal Provisions and are
   provided without warranty as described in the Revised BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
     1.1.  The Sustainability Telemetry Standard Specification . . .   4
     1.2.  Requirements language . . . . . . . . . . . . . . . . . .   7
   2.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   7
   3.  Motivation  . . . . . . . . . . . . . . . . . . . . . . . . .   7
   4.  Next Steps  . . . . . . . . . . . . . . . . . . . . . . . . .   8
     4.1.  The Sustainability Framework  . . . . . . . . . . . . . .   8
     4.2.  Further Development . . . . . . . . . . . . . . . . . . .   9
   5.  Use Cases . . . . . . . . . . . . . . . . . . . . . . . . . .   9
     5.1.  Use Case I  . . . . . . . . . . . . . . . . . . . . . . .   9
       5.1.1.  Scenario  . . . . . . . . . . . . . . . . . . . . . .   9
       5.1.2.  Sustainability Insights Added Value . . . . . . . . .  10
     5.2.  Use Case II . . . . . . . . . . . . . . . . . . . . . . .  10
       5.2.1.  Scenario  . . . . . . . . . . . . . . . . . . . . . .  10
       5.2.2.  Sustainability Insights Added Value . . . . . . . . .  10
     5.3.  Use Case III  . . . . . . . . . . . . . . . . . . . . . .  10
       5.3.1.  Scenario  . . . . . . . . . . . . . . . . . . . . . .  10
       5.3.2.  Sustainability Insights Added Value . . . . . . . . .  11
     5.4.  Use Case IV . . . . . . . . . . . . . . . . . . . . . . .  11
       5.4.1.  Scenario  . . . . . . . . . . . . . . . . . . . . . .  11
       5.4.2.  Sustainability Insights Added Value . . . . . . . . .  11
     5.5.  Use Case V  . . . . . . . . . . . . . . . . . . . . . . .  11
       5.5.1.  Scenario  . . . . . . . . . . . . . . . . . . . . . .  11
       5.5.2.  Sustainability Insights Added Value . . . . . . . . .  12
   6.  Deployment Considerations . . . . . . . . . . . . . . . . . .  12
   7.  Security Considerations . . . . . . . . . . . . . . . . . . .  13
   8.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  13
     8.1.  Normative References  . . . . . . . . . . . . . . . . . .  13
     8.2.  Informative References  . . . . . . . . . . . . . . . . .  14
   Change log  . . . . . . . . . . . . . . . . . . . . . . . . . . .  14
   Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . .  14
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  15

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1.  Introduction

   To answer questions about how sustainable equipment and operational
   practices are, various key performance indicators (KPIs) produced by
   network devices, management systems, and networking solutions are
   necessary.  While such KPIs are abundantly produced and collected
   today there are quite a few issues with their usability and
   commonality.  Without a common definition of metrics across the
   industry and widespread adoption, we will be left with ill-defined,
   potentially redundant, and proprietary metrics.

   An aspect lacking today is the precise definitions of the collected
   metrics.  This leads to KPIs that are not comparable to each other,
   as it is unknown what is included in the outcomes and what is not.
   It makes it challenging to sum or compare numbers from different
   manufacturers and organizations without investing in data
   normalization and a high number of assumptions.

   To produce aggregate data, it is also important to consider how the
   component inputs are combined.  Different vendors and operators might
   do this aggregation differently, yet again producing values that are
   hard to combine or compare when also using different units of
   measurement.  In many cases, one might suspect the actual numbers are
   underestimated, since there is competitive pressure to produce small
   numbers to report on the environmental impact of Internet
   communications and applications in contrast with the benefit of using
   it.  The aim shall not be to "produce the numbers" but to find
   quantitative measures, when possible, that give a fair assessment of
   Sustainability related metrics vs. useful work.

   It may be tempting to define the useful work in networking equipment
   as simply as the number of bits that are passing through the device.
   For some types of equipment, that might be appropriate, but clearly a
   video system that is sending a video stream with better video
   compression is not necessarily less sustaiable just because it sends
   fewer bits per Joule.  There are also many kinds of networking
   equipment where measuring the end user value in number of passed bits
   is obviously ridiculous, and other metrics have to be defined.
   Monitoring or management systems are examples of this.

   Another important and key aspect, when referring to environmental
   impact metrics is what needs to be considered as part of the
   lifecycle.  Life cycle assessment, also known as LCA, of networks and
   services, is defined by ISO 14040 as the compilation and evaluation
   of the inputs, outputs, and potential environmental impacts
   throughout its lifecycle.

   LCA is based on four main phases:

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   *  Goal and Scope

   *  Inventory Analysis

   *  Impact Assessment

   *  Interpretation

   This document is setting up the stage to identify data quality
   requirements, under the information and communications technology
   (ICT) category.  Following product Lifecycle Accounting (LCA), this
   document focuses on using the five product lifecycle stages defined
   by the GHG Protocol Accounting and Reporting Standard, which is in
   accordance with the ISO 14040:44 standards:

   1.  Use

   2.  Manufacturing

   3.  Material Acquisition / Processing

   4.  Transport

   5.  End of Life

   Impact and interpretation will be briefly covered under the
   document's motivation and use cases sections.

   There is reason to suspect that nebulous definitions combined with
   the competitive pressure might produce greenwashing.  Greenwashing
   involves making an unsubstantiated claim to deceive consumers into
   believing that a vendor's product or solution is environmentally
   friendly or has a greater positive environmental impact than it does.
   This document proposes the following initiative to counter these
   effects.

1.1.  The Sustainability Telemetry Standard Specification

   As an industry, we need to cooperate and agree on a set of core KPIs
   that are measured, including the definition of terms, units, and
   measurement procedures.  What is included, and what is not included.

   Sustainability metrics require a broad diversity of data sources that
   need to be combined.

   *  Static information.  Data coming from manufacturing, including
      reference values on how the assets have been designed if they
      enable reuse and recycling, and which materials have been used

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      during manufacturing and packaging; normally this information is
      defined once and it is part of data sheets provided by the
      vendors.

   *  Dynamic data.  Information measured in real-time or close to real-
      time from the networking equipment or application.  For instance,
      metrics should consider current inventory and current source and
      amount of consumed power, as well as what hardware and software
      features are enabled and used by the specific network equipment.

   *  Best practices.  Recommendations for optimizing the use of the
      network equipment, throughout its complete lifecycle.

   *  Local context.  Country-specific regulations, corporate policy,
      and social aspects.

   To enable the exchange of sustainability data among all interested
   parties, deployment considerations that are out of the scope of this
   document will need to include:

   *  Data models.  The model definition can be implemented in different
      forms.  This document proposes YANG as part of the Specification
      Data Model.  YANG can be used independently of the transport and
      can be converted into any encoding format supported by the network
      configuration protocol.  YANG models are decoupled from the
      management protocol layer.

   *  Sustainability framework.  To drive adoption, we propose an open-
      source aggregation framework for sustainability data.  This
      framework should be seen as a reference architecture for a
      sustainability monitoring mechanism.  While each implementation
      may be (and will be) different, the basic framework shall remain
      constant.  The framework must account for vendor-specific
      calculations and enhacements in a plug-in architecture.

   YANG data models as part of the Sustainability Telemetry
   Specification, which will follow this document, have been classified
   as follows:

   *  Identification of the assets.  Assets include hardware (physical
      as well as virtual), software, applications, and services.  The
      asset concept is defined in the Data Model for Lifecycle
      Management and Operations (DMLMO)
      [I-D.draft-palmero-opsawg-dmlmo-09] IETF draft.

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   *  Power and Efficiency.  To measure power consumption and energy
      efficiency, common methods, attributes, and units are needed to
      define metrics.  The approach needs to cover the different
      networking domains, starting with hardware focus, but including
      software and protocols attributes and metrics.

   *  Circular Economy attributes.  Collecting circularity data (such as
      materials used, or the embedded emissions footprint) is expensive
      and difficult because of confidentiality and the non-standardized
      approach to reporting and exchanging circularity data.  The flow
      of circularity data is typically lost at each step throughout the
      supply chain, as goods are passed through suppliers,
      manufacturers, system integrators, distributors, customers, and
      consumers into reuse and recycling.

   *  Context metrics.  Without understanding the context of the use,
      none of the metrics listed above will provide much value.  The
      carbon intensity of the power used, for example, is key to
      assessing the sustainability of a given application.  An
      efficiency number needs to be interpreted differently at peak
      hours and night.  A given user may be considered less sustainable
      if someone demonstrates the ability to deliver the same end-user
      value to a smaller footprint.  A system that is transported a
      shorter distance or using a more sustainable mode of
      transportation from the factory to the installation site may also
      be assessed more positively.  Or if it has a longer economic life
      or comes with less single-use packaging.

   The model definition can be implemented in different forms.  We would
   like to propose a specific YANG model for the sustainability metrics,
   which intrinsically allows for a variety of collection protocols.
   YANG can be used independently of the transport protocol, and lends
   itself well to be converted into a variety of encoding formats
   supported by popular network configuration protocols.

   The rest of this document is organized as follows.  Section 2
   establishes the terminology and abbreviations.  Section 3 outlines
   the goals and motivation of Sustainability metrics.  Section 4
   discusses Use Cases that lay out the groundwork for the
   Sustainability Telemetry Specification, to address new business needs
   introduced by the Circular Economy and to avoid excessive climate
   change.

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1.2.  Requirements language

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in
   BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
   capitals, as shown here.

2.  Terminology

   Terminology and abbreviations used in this document:

   Asset  Hardware, software, applications, or services.  An asset can
      be physical or virtual.

   Greenwashing  Marketing (intentionally or not) an asset as being
      green (i.e. fitting well into the circular economy) by selectively
      omitting less green aspects of the asset.

   Circular economy  An economic paradigm in which the full lifecycle
      cost of resource use and emissions are included.

   Climate change  The disruption of ecological processes caused by
      excessive resource use or emissions.

3.  Motivation

   Aside from the need for consistency on metrics to be considered as
   part of the ICT sector, to reduce environmental impact and increase
   benefit; this document and future work related, aim to support the
   Digital Product Passport initiative under the European Union's (EU's)
   Circular Economy Action Plan (CEAP) and the Ecodesign for Sustainable
   Products Regulation (ESPR).  There is not much time for businesses to
   prepare and for IETF work to influence this development.

   The Digital Product Passport (DPP) is key to the EU's transition to a
   circular economy and will provide information about assets'
   environmental sustainability.  It aims to improve traceability and
   transparency along the entire value chain of an asset and to improve
   the management and sharing of product-related data which are critical
   to ensuring their sustainable use, prolonged life, and circularity.

   There is a need to:

   *  Track raw materials extraction/production, supporting due
      diligence efforts

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   *  Enable manufacturers to increase transparency in the value chain,
      better compliance, increased circularity, and sustainability

   *  Enabling services related to its remanufacturing, reparability,
      second-life, and recyclability, enabling sustainable business
      models.

   In the case of upgrading, repairing, repurposing, or remanufacturing
   a product, it should be clear the responsibility to update the
   information is transferred to the installer, repairer, or
   remanufacturer who will be putting the product into service or
   placing it on the EU market.

   The three main target groups of the passport are:

   *  Public authorities and policymakers: reliable information on
      compliance of products with EU legislation

   *  Economic operators (such as recyclers): information on proper
      dismantling and waste treatment of products; the presence of
      Substances of Very High Concern (SVHCs) through a link to the SCIP
      database; etc.

   *  Consumers: instructions for use, information on repair centers,
      sorting instructions, and other information as required by
      existing EU legislation (e.g.  CLP regulations), more information
      about products would be made available to consumers and customers
      to enable informed choices.

   The DPP will help business planners and consumers make informed
   choices when purchasing assets, and should also help local and public
   authorities to better perform checks and controls.

4.  Next Steps

   To enable the exchange of sustainability data among all interested
   parties at each step of the value supply chain, a technical
   sustainability framework for how this data is queried, transported,
   and visualized will be required.

4.1.  The Sustainability Framework

   To drive quick adoption, we propose to build an open-source
   aggregation framework for sustainability data.  This framework should
   be seen as a reference architecture for a sustainability monitoring
   mechanism.  The reference implementation will be based on the IETF
   standards mentioned before.  The architecture would supply a few base
   components, but otherwise, allow vendors or standards bodies to

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   plugin their applications that fit in the general framework.  One
   example of such an application that we would like to propose is a
   model to calculate the Total Sustainability Cost of Ownership (TSCO)
   for network solutions based on the Environmental, Social, and
   Governance (ESG) Materiality Matrix.  This matrix model is open to
   adding any implementation that takes into consideration
   Sustainability objectives at a point in time, but it also evolves
   with the needs of the business and the stakeholders.  The initial
   scope proposes to investigate the top four most important ESG
   Materiality issues as a base to grow the TCO to a TSCO that matches
   the Company's priorities and issues.

4.2.  Further Development

   Items that are not in the scope of this edition of this document, but
   could be addressed in future revisions, include:

   *  How to relate Sustainability Telemetry Specification to
      sustainability Scopes 1, 2, and 3,

   *  Circular Economy Business models,

   *  Recommendations,

   *  Scope 4, i.e. metrics for avoided footprints (sometimes called
      handprint).  For instance, to reduce GHG emissions, automation
      activities like Zero Touch, or certain technologies like Routed
      Optical Networking, can replace other higher emitting activities.
      Another example would be the positive impact arising from video
      conferencing as opposed to international travel by airplane.

5.  Use Cases

5.1.  Use Case I

5.1.1.  Scenario

   An organization is running a large and complex network with many
   types of devices.  By looking at the utility bills, it is clear that
   the organization is consuming rather more energy per transported bit
   than many other organizations.  Exactly which devices or network
   functions are at the root of the situation is unclear, however.

   The product LCA in this scenario applies to the stage of "Use".

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5.1.2.  Sustainability Insights Added Value

   By providing near-real-time data that is broken down at least to an
   individual hardware device, and ideally considerably deeper than
   that, it will be possible to attribute energy and environmental
   footprint costs to different device types, service types, and
   individual customers.

   If one customer is altering its behavior or load on the network, a
   monitoring application could detect this quickly.  It would also be
   possible to try several implementations or configurations for a given
   service and get quick feedback on the operations cost of that change.

5.2.  Use Case II

5.2.1.  Scenario

   An organization is running a network with a variety of managed
   services and applications.  Some of the devices are getting old, and
   have lower energy efficiency than more modern devices.  Replacing old
   devices with new ones might improve efficiency, but has an economical
   as well as environmental cost.  Without specific performance data, it
   is difficult to make informed decisions about upgrades.

   The product LCA stage applies to "Use".

5.2.2.  Sustainability Insights Added Value

   By providing KPIs for reading sustainability parameters that pertain
   to actual usage, rather than numbers from data sheets, the accuracy
   of upgrade decisions is enhanced.  Such data can make the case for an
   upgrade very clear and easy to make, or it may show that it's not a
   good idea at this time.  In both cases improving the sustainability
   of the operations.

5.3.  Use Case III

5.3.1.  Scenario

   Recycling and reuse are major drivers of the circular economy.
   Companies must put high efforts in this direction and transparency.
   This is a qualitative KPI, passed if percentages of recycled and
   reused goods given the manufacturing options, as well as reports
   listing how many units have been recycled.

   The product LCA applies to the stage of "Material Acquisition /
   Processing".

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5.3.2.  Sustainability Insights Added Value

   The trend seems to be to report on the percentage of recycled user
   devices and the eco-design and refurbishment efforts.  Sustainability
   Insights can enable the data sources to report comprehensive
   reporting of recycling efforts.

5.4.  Use Case IV

5.4.1.  Scenario

   An organization is running a network with a variety of managed
   services and applications.  The network and application performance
   is continuously monitored, and there are even some automatic
   remediation actions that may trigger when certain conditions are
   detected.

   In this scenario, the product LCA applies to the stage of "Use".

5.4.2.  Sustainability Insights Added Value

   By providing KPIs for sustainability parameters such as power
   consumption and power efficiency, the monitoring system can access
   relevant data and perform actions that reduce the power consumption
   or sustainability footprint of the delivered services.

   For example, some overly redundant links or systems may be powered
   off at night, or enter into a low-power mode.  A highly available
   application may be configured to take more load in the data center
   with a lower price of energy, lower outside temperatures, or an
   environmentally superior energy mix.

5.5.  Use Case V

5.5.1.  Scenario

   IT solutions are currently analyzed from two main perspectives:
   technological and economical.  When looking at environmental, social,
   and corporate governance (ESG) impact topics, sustainability metrics
   in the context of digital transformation, deliver insights into
   opportunities and risks that emerge from a rapidly growing
   stakeholder demand for sustainable, digitally advanced products and
   services.

   The product LCA applies to all stages under the product LCA.

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5.5.2.  Sustainability Insights Added Value

   From an application point of view, this use case proposes to include
   Sustainability factors in the Total Cost of Ownership (TCO)
   calculation, where there is a need to add Environmental, Social, and
   Governmental Key Performance Indicators (KPIs) to the analysis.
   However, adding Sustainability metrics comes with challenges and
   trades-off.  Future work considers a model to calculate the Total
   Sustainability Cost of Ownership (TSCO) for network solutions based
   on the ESG Materiality Matrix.  This model is open to adding any
   implementation that takes into consideration Sustainability
   objectives at a point in time, but it also evolves with the needs of
   the business and the stakeholders.  The initial scope proposes to
   investigate the top four most important ESG Materiality issues as a
   base to grow the TCO to a TSCO that matches the Company's priorities
   and issues.

   Future work might include use cases that will cover "Manufacturing",
   "Transport" and "End of Life" examples.

6.  Deployment Considerations

   Sustainability Data Models defines the data schemas for
   Sustainability Insights data.  Sustainability Insights Data Models
   are based on YANG.  YANG data models can be used independently of the
   transport protocols and can be converted into any encoding format
   supported by the network configuration protocol.  YANG is protocol
   independent.

   To enable the exchange of Sustainability Insights data among all
   interested parties, deployment considerations that are out of the
   scope of this document will need to include:

   *  The data model definition

   *  The data structure to describe all metrics and quantify relevant
      data consistently, i.e. specific formats like XML or JSON encoded
      messages would be deemed valid or invalid based on Sustainability
      Insights models.

   *  The process to share and collect Sustainability Insights data
      across the consumers consistently, including the transport
      mechanism.  The Sustainability Insights YANG models can be used
      with network management protocols such as NETCONF [RFC6241],
      RESTCONF [RFC8040], streaming telemetry, etc.  OpenAPI
      specifications might also help to consume Sustainability Insights
      metrics.

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   *  How the configuration of assets to implement Sustainability
      Insights telemetry should be done.

   It will be important to consider where, when, and how often the data
   will need to be collected.  As per the specification of the data,
   data might need to be collected from different data sources: network
   devices, and different databases where manufacturing information is
   stored and maintained.  Ideally all this information can be extracted
   via a well-defined API.  The frequency to collect the data will also
   vary, for instance, comparing manufacturing data with runtime data.
   For example, it might be a good practice to collect inventory data
   once per day, while "environmental" data might need to be updated
   hourly or even more frequently.  It will also be important to
   consider the platform from where data might be collected, and the
   need to properly correlate all the information.

7.  Security Considerations

   The security considerations mentioned in section 17 of [RFC7950]
   apply.

   Sustainability Insights brings several security and privacy
   implications because of the various components and attributes of the
   information model.  For example, each functional component can be
   tampered with to give manipulated data.  Sustainability Insights when
   used alone or with other relevant data, can identify an individual,
   revealing Personal Identifiable Information (PII).  Misconfigurations
   can lead to data being accessed by unauthorized entities.

   Methods exist to secure the communication of management information.
   The transport entity of the functional model MUST implement methods
   for secure transport.  This document also contains an Information
   model and Data-Model in which none of the objects defined are
   writable.  If the objects are deemed sensitive in a particular
   environment, access to them MUST be restricted using appropriately
   configured security and access control rights.  The information model
   contains several optional elements which can be enabled or disabled
   for the sake of privacy and security.  Proper authentication and
   audit trail MUST be included for all the users/processes that access
   Sustainability Insights Telemetry Data.

8.  References

8.1.  Normative References

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   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/info/rfc2119>.

   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <https://www.rfc-editor.org/info/rfc8174>.

8.2.  Informative References

   [I-D.draft-palmero-opsawg-dmlmo-09]
              Palmero, M., Brockners, F., Kumar, S., Bhandari, S.,
              Cardona, C., and D. Lopez, "Data Model for Lifecycle
              Management and Operations", Work in Progress, Internet-
              Draft, draft-palmero-opsawg-dmlmo-09, 17 January 2023,
              <https://datatracker.ietf.org/doc/html/draft-palmero-
              opsawg-dmlmo-09>.

   [RFC6241]  Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,
              and A. Bierman, Ed., "Network Configuration Protocol
              (NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011,
              <https://www.rfc-editor.org/info/rfc6241>.

   [RFC7950]  Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
              RFC 7950, DOI 10.17487/RFC7950, August 2016,
              <https://www.rfc-editor.org/info/rfc7950>.

   [RFC8040]  Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
              Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017,
              <https://www.rfc-editor.org/info/rfc8040>.

Change log

   RFC Editor Note: This section is to be removed during the final
   publication of the document.

   version 00

   *  Initial version of the draft.

Acknowledgments

   This document was created by meaningful contributions from Jeff
   Apcar, Klaus Verschure and Suresh Krishnan.

   The authors wish to thank them and many others for their helpful
   comments and suggestions.

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Internet-Draft           Sustainability Insights              March 2023

Authors' Addresses

   Per Andersson
   Cisco Systems
   Email: perander@cisco.com

   Jan Lindblad
   Cisco Systems
   Email: jlindbla@cisco.com

   Snezana Mitrovic
   Cisco Systems
   Email: snmitrov@cisco.com

   Marisol Palmero
   Cisco Systems
   Email: mpalmero@cisco.com

   Esther Roure
   Cisco Systems
   Email: erourevi@cisco.com

   Gonzalo Salgueiro
   Cisco Systems
   Email: gsalguei@cisco.com

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