Getting Ready for Energy-Efficient Networking                 E. Stephan
Internet-Draft                                                    Orange
Intended status: Informational                                M. Palmero
Expires: 17 November 2025                            Cisco Systems, Inc.
                                                               B. Claise
                                                                   Q. Wu
                                                                  Huawei
                                                         L. M. Contreras
                                                              Telefonica
                                                         C. J. Bernardos
                                        Universidad Carlos III de Madrid
                                                             16 May 2025


               Use Cases for Energy Efficiency Management
                    draft-stephan-green-use-cases-01

Abstract

   This document groups use cases for Energy efficiency Management of
   network devices.

   Discussion Venues

   Source of this draft and an issue tracker can be found at
   https://github.com/emile22/draft-stephan-green-use-cases

About This Document

   This note is to be removed before publishing as an RFC.

   The latest revision of this draft can be found at
   https://emile22.github.io/draft-stephan-green-use-cases/draft-
   stephan-green-use-cases.html.  Status information for this document
   may be found at https://datatracker.ietf.org/doc/draft-stephan-green-
   use-cases/.

   Discussion of this document takes place on the Getting Ready for
   Energy-Efficient Networking Working Group mailing list
   (mailto:green@ietf.org), which is archived at
   https://mailarchive.ietf.org/arch/browse/green/.  Subscribe at
   https://www.ietf.org/mailman/listinfo/green/.

   Source for this draft and an issue tracker can be found at
   https://github.com/emile22/draft-stephan-green-use-cases.






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Status of This Memo

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   This Internet-Draft will expire on 17 November 2025.

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   Copyright (c) 2025 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
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Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
   2.  Use Cases . . . . . . . . . . . . . . . . . . . . . . . . . .   3
     2.1.  Incremental Application of the GREEN Framework  . . . . .   4
     2.2.  Selective reduction of energy consumption in network parts
            proportional to traffic levels . . . . . . . . . . . . .   5
     2.3.  Reporting on Lifecycle Management . . . . . . . . . . . .   6
       2.3.1.  Carbon Reporting  . . . . . . . . . . . . . . . . . .   6
       2.3.2.  Energy Mix  . . . . . . . . . . . . . . . . . . . . .   6
     2.4.  Real-time Energy Metering of Virtualised or Cloud-native
            Network Functions  . . . . . . . . . . . . . . . . . . .   6
     2.5.  Indirect Energy Monitoring and control  . . . . . . . . .   7
     2.6.  Consideration of other domains for obtention of end-to-end
            metrics  . . . . . . . . . . . . . . . . . . . . . . . .   7
     2.7.  Dynamic adjustment of network element throughput according
            to traffic levels in wireless transport networks . . . .   8



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     2.8.  Video streaming use case  . . . . . . . . . . . . . . . .   8
     2.9.  WLAN Network Energy Saving  . . . . . . . . . . . . . . .   9
     2.10. Fixed Network Energy Saving . . . . . . . . . . . . . . .  11
     2.11. Energy Efficiency Network Management  . . . . . . . . . .  11
     2.12. ISAC-enabled Energy-Aware Smart City Traffic
            Management . . . . . . . . . . . . . . . . . . . . . . .  11
       2.12.1.  Use case description . . . . . . . . . . . . . . . .  11
       2.12.2.  GREEN Specifics  . . . . . . . . . . . . . . . . . .  12
       2.12.3.  Requirements for GREEN . . . . . . . . . . . . . . .  12
     2.13. Double Accounting Open issue  . . . . . . . . . . . . . .  13
   3.  Security Considerations . . . . . . . . . . . . . . . . . . .  14
   4.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  14
   5.  Acknowledgments . . . . . . . . . . . . . . . . . . . . . . .  14
   6.  Use Cases Living List . . . . . . . . . . . . . . . . . . . .  15
   7.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  15
     7.1.  Normative References  . . . . . . . . . . . . . . . . . .  15
     7.2.  Informative References  . . . . . . . . . . . . . . . . .  16
   8.  Appendix  . . . . . . . . . . . . . . . . . . . . . . . . . .  16
   9.  Informative References  . . . . . . . . . . . . . . . . . . .  16
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  17

1.  Introduction

   This document groups use cases collected from operators and from
   discussions since the GREEN WG preparations.

   It provides a set of use cases for Energy efficiency Management of
   network devices.  The scope is devices like switches, routers,
   servers and storage devices having an IP address providing a
   management interface.  It includes their built-in components that
   receive and provide electrical energy.

   In annex we recall the framework where the use cases can be put in
   situation.

2.  Use Cases

   This section describes a number of relevant use cases with the
   purpose of elicit requirements for Energy Efficiency Management.
   This is a work in progress and additional use cases will be
   documented in next versions of this document.  Use cases which are
   not tied enough to the current GREEN chater will be moved to the
   GREEN WG wiki pages or to other WGs or RGs.








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2.1.  Incremental Application of the GREEN Framework

   This section describes an incremental example [legacy-path] of usage
   showing how a product, a service and a network can use the framework
   in different settings.

   This use case is the less trendy of all the use cases by far as its
   ambitious is limited to migration and coexistence, as usual.
   Nevertheless from a telco perspective, it is the centrality for 2
   main reasons:

   *  to start immediatly the move to energy efficiency using legacy
      devices;

   *  to account the gain of the move one started;

   Once upon a time there was an very old legacy router named Rusty
   equipped with outdated ethernet and ugly optical interfaces.  Despite
   his worn-out appearance, Rusty was determined to contribute to the
   energy efficiency effort.  He dreamed of finding a way to optimize
   his old circuits and help reduce the power consumption of the network
   he had faithfully served for so many years.  Though he was no longer
   in his prime, Rusty believed that even an old router like him could
   make a difference in a world striving for sustainability and help
   reduce the carbon footprint.  He is convince that he still had a part
   to play in making the digital world a greener place.

   Device moving gradually to GREEN energy efficiency support:

   *  step 1 "baseline" : establishing a reference point of typical
      energy usage, which is crucial for identifying inefficiencies and
      measuring improvements over time.  At this step the controler use
      only the (c) part of the framework.  It is collected from the
      datasheet.

   By establishing a baseline and using benchmarking, you can determine
   if your networking equipment is performing normally or if it is "off"
   from expected performance, guiding you in making necessary
   improvements.












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   The initial measurement of your networking equipment's energy
   efficiency and performance, aka Baselining, needs to be in
   coordination with the vendor specifications and industry standards to
   understand what is considered normal or optimal performance. example:
   Baseline: Your switches operate at 5 Gbps per watt.  Benchmarking:
   Vendor specification is 8 Gbps per watt; industry standard is 10 Gbps
   per watt.  Action: Implement energy-saving measures and upgrades.
   Tracking: Measure again to see if efficiency improves towards 8-10
   Gbps per watt.

   *  step 2 "component": part of the device hw or sw migrated to
      support GREEN framework elements.

   *  step 3 "device controleur"

   *  step 4 "network level"

   (i) Avoid a power-on/power-off frequency to break component parts
   (aka laser, power parts, wire connectors ...)

   (ii) the gain must be measurable

   (iii) network-wide energy efficiency solutions must include legacy
   devices and green-wg ready devices

2.2.  Selective reduction of energy consumption in network parts
      proportional to traffic levels

   Traffic levels in a network follow patterns reflecting the behavior
   of consumers.  Those patterns show periodicity in the terms of the
   traffic delivered, that can range from daily (from 00:00 to 23:59) to
   seasonal (e.g., winter to summer), showing peaks and valleys that
   could be exploited to reduce the consumption of energy in the network
   proportionally, in case the underlying network elements incorporate
   such capabilities.  The reduction of energy consumption could be
   performed by leveraging on sleep modes in components up to more
   extreme actions such as switching off network components or modules.
   Such decisions are expected to no impact on the service delivered to
   customers, and could be accompanied by traffic relocation and / or
   concentration in the network.











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2.3.  Reporting on Lifecycle Management

   Lifecycle information related to manufacturing energy costs,
   transport, recyclability, and end-of-life disposal impacts is part of
   what is called "embedded carbon."  This information is considered to
   be an estimated value, which might not be implemented today in the
   network devices.  It might be part of the vendor information, and to
   be collected from datasheets or databases.  In accordance with ISO
   14040/44, this information should be considered as part of the
   sustainable strategy related to energy efficiency.  Also, refer to
   the ecodesign framework [(EU) 2024/1781] published in June by the
   European Commission.

2.3.1.  Carbon Reporting

   To report on carbon equivalents for global reporting, it is important
   to correlate the location where the specific entity/network element
   is operating with the corresponding carbon factor.  Refer to the
   world emission factor from the International Energy Agency (IEA),
   electricity maps applications that reflect the carbon intensity of
   the electricity consumed, etc.

2.3.2.  Energy Mix

   Energy efficiency is not limited to reducing the energy consumption,
   it is common to include carbon free, solar energy, wind energy,
   cogeneration in the efficiency.

   The type of the sources of energy of the power is one criteria of
   efficiency.

   There are other dimensions that must visible: As many telecom
   locations include battery or additionnally several backups levels (as
   example battery, standby generator ...) there is a requirement to
   known exactly when a backup power is in used and which one is.

2.4.  Real-time Energy Metering of Virtualised or Cloud-native Network
      Functions

   Facilitating more precise and real-time estimations of energy
   consumed by virtualised or cloud-native network functions.

   Effective metering of virtualized network infrastructure is critical
   for the efficient management and operation of next-generation mobile
   networks [GREEN_NGNM].






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2.5.  Indirect Energy Monitoring and control

   There are cases where Energy Management for some devices need to
   report on other entities.  There are two major reasons for this.

   o For monitoring energy consumption of a particular entity, it is not
   always sufficient to communicate only with that entity.  When the
   entity has no instrumentation for determining power, it might still
   be possible to obtain power values for the entity via communication
   with other entities in its power distribution tree.  A simple example
   of this would be the retrieval of power values from a power meter at
   the power line into the entity.  A Power Distribution Unit (PDU) and
   a Power over Ethernet (PoE) switch are common examples.  Both supply
   power to other entities at sockets or ports, respectively, and are
   often instrumented to measure power per socket or port.  Also it
   could be considered to obtain power values for the entity via
   communication with other entities outside of the power distribution
   tree, like for example external databases or even data sheets.

   o Similar considerations apply to controlling the power supply of an
   entity that often needs direct or indirect communications with
   another entity upstream in the power distribution tree.  Again, a PDU
   and a PoE switch are common examples, if they have the capability to
   switch power on or off at their sockets or ports, respectively.

2.6.  Consideration of other domains for obtention of end-to-end metrics

   The technologies under the scope of IETF provide the necessary
   connectivity to other technological domains.  For the obtention of
   metrics end-to-end it would be required to combine or compose the
   metrics per each of those domains.

   An exemplary case is the one of a network slice service.  The concept
   of network slice was initially defined by 3GPP [TS23.501], and it has
   been further extended to the concerns of IETF [RFC9543].

   In regards energy efficiency, 3GPP defines a number of energy-related
   key performance indicators (KPI) in [TS28.554], specifically Energy
   Efficiency (EE) and Energy Consumption (EC) KPIs.  There are KPIs
   particular for a slice supporting a specific kind of service (e.g.,
   Mobile Broadband or MBB), or generic ones, like Generic Network Slice
   EE or Network Slice EC.  Assuming these as the KPIs of interest, the
   motivation of this use case is the obtention of the equivalent KPIs
   at IETF level, that is, for the network slice service as defined in
   [RFC9543].






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   Note that according to [TS28.554], the Generic Network Slice EE is
   the performance of the network slice divided by the Network Slice EC.
   Same approach can be followed at IETF level.  Note that for avoiding
   double counting the energy at IETF level in the calculation of the
   end-to-end metric, the 3GPP metric should only consider the
   efficiency and consumption of the 3GPP-related technologies.

2.7.  Dynamic adjustment of network element throughput according to
      traffic levels in wireless transport networks

   Radio base stations are typically connected to the backbone network
   by means of fiber or wireless transport (e.g., microwave)
   technologies.  In the specific case of wireless transport, automation
   frameworks have been defined [ONF-MW][RFC8432][mWT025] for their
   control and management.

   One of the parameters subject of automated control is the power of
   the radio links.  The relevance of that capability is that the power
   can be adjusted accordingly to the traffic observed.  Wireless
   transport networks are typically planned to support the maximum
   traffic capacity in their area of aggregation, that is, the traffic
   peak.  With that input, the number of radio links in the network
   element and the corresponding power per radio link (for supporting a
   given modulation and link length in the worst weather conditions) are
   configured.  This is done to avoid any kind of traffic loss in the
   worst operational situation.  However, such operational needs are
   sporadic, giving room for optimization during normal operational
   circumstances and/or low traffic periods.

   Power-related parameters are for instance defined in [RFC8561].
   Those power parameters can be dynamically configured to adjust the
   power to the observed traffic levels with some coarse granularity,
   but pursuing certain degrees of proportionality.

2.8.  Video streaming use case

   Video streaming is nowadays the major source of traffic observed in
   ISP networks, in a propotion of 70% or even higher.  Over-the-top
   distribution of streaming traffic is typically done by delivering a
   unicast flow per end user for the content of its interest.In
   consequence, during the hours of higher demand, the total traffic in
   the network is proportional to the concurrence of users consuming the
   video streaming service.  The amount of traffic is also dependent of
   the resolution of the encoded video (the higher the resolution, the
   higher the bit rate per video flow), which tends to be higher as long
   as the users devices support such higher resolutions.





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   The consequence of both the growth in the number of flows to be
   supported simultaneously, and the higher bit rate per flow, is that
   the nework elements in the path between the source of the video and
   the user have to be dimensioned accordingly.  This implies the
   continuous upgrade of those network elements in terms of capacity,
   with the need of deploying high-capacity network elements and
   components.  Apart from the fact that this process is shortening the
   lifetime of network elements, the need of high capacity interfaces
   also increase the energy consumption (despite the effort of
   manufacturers in creating more efficient network element platforms).
   Note that nowadays there is no actual possibility of activating
   energy consumption proportionality (in regards the delivered traffic)
   to such network elements.

   As a mean of slowing down this cycle of continuos renewal, and reduce
   the need og higher bit rate interfaces / line cards, it seems
   convenient to explore mechanisms that could reduce the volume of
   traffic without impacting the user service expectations.  Variants of
   multicast or different service delivery strategies can help to
   improve the energy efficiency associated to the video streaming
   service.  It should be noted that another front for optimization is
   the one related to the deployment of cache servers in the network.

2.9.  WLAN Network Energy Saving

   In a WLAN network, The AP is usually powered by a PoE switch.  AP
   nodes are network devices with the largest number and consuming most
   of energy.  Therefore, the working status of the AP is the core of
   the energy saving solution.

   The working status of the AP can be break down into 3 modes as
   follows: PoE power-off mode: In this mode, the PoE switch shuts down
   the port and stops supplying power to the AP.  The AP does not
   consume power at all.  When the AP wakes up, the port provides power
   again.  In this mode, it usually takes a few minutes for the AP to
   recover.  Hibernation mode: Only low power consumption is used to
   protect key hardware such as the CPU, and other components are shut
   down.  Low power consumption mode: Compared with the hibernation
   mode, the low power consumption mode maintains a certain
   communication capability.  For example, the AP retains only the 2.4
   GHz band and disables other radio bands.

   In energy saving deployment, after the surrounding energy saving APs
   are shut down, the Working AP automatically adjusts their transmit
   power to increase the coverage of the entire area at specific energy
   saving period.  In such case, energy saving APs can freely choose to
   switch to any mode we described above.




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      /---\
     |     +-----+
     | AP  |     |
      \---/      |      +------------+
                 |      |            |
                 |------+     PoE    |
      /---\      |      |   Switch   |
     |     |     |      +------------+
     | AP  +-----+
      \---/

                        Figure 1: PoE Power Off Mode

                    4                         4
    +----------+   \|/        +----------+   \|/
    |          |    |         |          |    |
    |   +----+ |    |         |   +----+ |    |
    |   |5GHz+-+----+         |   |5GHz+-+-X--+
    |   | RF | |    2         |   | RF | |    2
    |   +----+ |   \|/    \   |   +----+ |   \|/
    |   +----+ |    |   ---\  |   +----+ |    |
    |  2.4GHz| |    |       \ |  2.4GHz| |    |
    |   | RF +-+----+       / |   | RF +-+-X--+
    |   +----+ |    2   ---/  |   +----+ |    2
    |   +----+ |   \|/    /   |   +----+ |   \|/
    |  2.4GHz| |    |         |  2.4GHz| |    |
    |   | RF |-+----+         |   | RF +-+----+
    |   +----+ |              |   +----+ |
    +----------+              +----------+

                    Figure 2: Low Power Consumption Mode

        +--+  +--+    +--+
        |AP|--|AP|--- |AP|      ------------------------------
        +--+  +--+   \+--+      Grouping  Recommended
        /               \        Area     Energy Saving Period
     +--+     +--+      +--+    ------------------------------
     |AP|     |AP|      |AP|    XED01-1  01:00:00,06:30:00
     +--+     +--+      +--+
       |                 |      ------------------------------
        +--+          +--+
        |AP|  +--+   /|AP|      XED01-2  01:30:00,06:30:00
        +--+--|AP|--- +--+     --------------------------------
              +--+

               Figure 3: Wireless Resource Management on APs





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2.10.  Fixed Network Energy Saving

   Traffic on the Tidal network has an obvious tidal period, including
   heavy-traffic periods and light-traffic periods: The time duration of
   heavy traffic load and light traffic load are clearly distinguished.
   The switching time between the heavy-traffic period and the light-
   traffic period is quite fixed and cyclic.  In a tidal network, some
   network devices can be shut down or sleep during low-traffic periods
   to save energy.  In the metro or backbone network, the routers
   support various different speed interfaces, e.g., the gigabit level
   to 10GE/50GE, or 100G to 400G.  Routers might choose to adjust speed
   of the interface or downgrade from high speed interface to low speed
   interface based on network traffic load changes to save the energy.
   In addition, the routers can adjust the number of working network
   processor cores and clock frequency of chipsets and the number of
   SerDes buses based on network traffic load changes to save the
   energy.

2.11.  Energy Efficiency Network Management

   Network level Energy Efficiency allows network operators not only see
   real time energy consumption in the network devices of large scale
   network, but also allow you see o which network devices enable energy
   saving, which devices not,which are legacy ones, o The total energy
   consumption changing trend over the time of the day, for all network
   devices, o Energy efficiency changing trend over the time of the day
   for the whole network.  With the better observability to energy
   consumption statistics data and energy efficiency statistics data,
   the network operators can know which part of the network need to be
   adjusted or optimized based on network status change.

2.12.  ISAC-enabled Energy-Aware Smart City Traffic Management

2.12.1.  Use case description

   Integrated Sensing and Communications (ISAC) is emerging as a key
   enabler for next-generation wireless networks, integrating sensing
   and communication functionalities within a unified system.  By
   leveraging the same spectral, hardware, and computational resources,
   ISAC enhances network efficiency while enabling new capabilities such
   as high-resolution environment perception, object detection, and
   situational awareness.  This paradigm shift is particularly relevant
   for applications requiring both reliable connectivity and precise
   sensing, such as autonomous vehicles, industrial automation, and
   smart city deployments.  Given its strategic importance, ISAC has
   gained significant traction in standardization efforts.  The ETSI
   Industry Specification Group (ISG) on ISAC has been established to
   explore technical requirements and use cases, while 3GPP has



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   initiated discussions on ISAC-related features within its ongoing
   research on future 6G systems.  Furthermore, research initiatives
   within the IEEE and IETF are investigating how ISAC can be integrated
   into network architectures, spectrum management, and protocol design,
   making it a critical area of development in the evolution of wireless
   networks.

   This use case involves deploying ISAC systems in a smart city to
   monitor and optimize vehicles' traffic flows while minimizing energy
   consumption of the mobile network.  The system integrates sensing
   technologies, such as radar and LIDAR, with communication networks to
   detect vehicle density, monitor road conditions, and communicate with
   autonomous vehicles or traffic lights.  By using ISAC, the system
   minimizes redundant infrastructure (e.g., separate sensors and
   communication equipment), thus reducing the overall carbon and energy
   footprint.

2.12.2.  GREEN Specifics

   Energy Consumption Monitoring: Each ISAC component (e.g., roadside
   units, integrated sensors, and communication transceivers) is capable
   of reporting its energy consumption in real time to the centralized
   or distributed energy management system.

   Reconfiguration for Energy Efficiency: The system can dynamically
   switch between high-resolution sensing modes (e.g., during peak
   hours) and low-power modes (e.g., during low traffic periods).  The
   network can reconfigure traffic communication paths to prioritize
   routes or nodes that consume less power, leveraging energy-efficient
   communication protocols.

   Integration of Local and Global Energy Goals: The system can operate
   both locally (e.g., turning off specific roadside units in low-
   traffic areas) and globally (e.g., modifying traffic patterns across
   the city) to achieve defined energy consumption goals.

2.12.3.  Requirements for GREEN

   1.  Measurement Granularity:

   *  Ability to measure energy consumption per ISAC component (e.g.,
      roadside unit, sensor, transceiver).

   *  Granular reporting per communication link or sensing mode (e.g.,
      high-power radar mode vs. low-power mode).

   1.  Power Control Mechanisms:




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   *  Ability to switch components on/off or place them in sleep/standby
      mode when not in use.

   *  Support for dynamic adjustment of sensing resolution or
      communication bandwidth to balance energy savings and system
      performance.

   1.  Reconfiguration and Adaptability:

   *  Support for hardware reconfiguration (e.g., adaptive sensing
      modes, transceiver settings) to optimize energy use.

   *  Mechanisms to steer traffic or adjust network routing based on
      global or local energy-saving objectives.

   1.  Global Coordination:

   *  Capabilities for cross-domain coordination to enable global
      optimization (e.g., city-wide traffic rerouting or dynamic
      resource allocation across different regions).

   *  Ability to aggregate and analyze energy consumption data from all
      ISAC components to inform high-level decision-making.

   1.  Energy-Aware Standards and Protocols:

       *  Communication protocols that minimize power usage while
          maintaining reliability.

       *  Interoperability standards for energy-aware reconfiguration
          across heterogeneous ISAC components and systems.

2.13.  Double Accounting Open issue

   Energy consumption monitoring often includes metering at both
   upstream and downstream levels of power distribution.  While this can
   provide granular visibility, it may also lead to double accounting if
   not carefully managed.

   A common case arises when energy is measured at the input of a Power
   Delivery Unit (PDU), and individually at each device powered by that
   PDU (e.g., servers, switches).  Since the PDU input already reflects
   the downstream consumption, summing the per-device values with the
   PDU input results in redundant reporting.  A similar issue occurs
   with Power over Ethernet (PoE) infrastructures when a network switch
   supply power directly to devices.  If the total power consumption
   measured encompasses both the power delivered to the PoE switch and
   to the powered devices, this again results in double accounting.



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   These 2 cases distort energy dashboards and indicators such as Power
   Usage Effectiveness (PUE).

3.  Security Considerations

   Resiliency is an implicit use case of energy efficiency management
   which comes with numerous security considerations :

   Controlling Power State and power supply of entities are considered
   highly sensitive actions, since they can significantly affect the
   operation of directly and indirectly connected devices.  Therefore,
   all control actions must be sufficiently protected through
   authentication, authorization, and integrity protection mechanisms.

   Entities that are not sufficiently secure to operate directly on the
   public Internet do exist and can be a significant cause of risk, for
   example, if the remote control functions can be exercised on those
   devices from anywhere on the Internet.

   The monitoring of energy-related quantities of an entity as addressed
   can be used to derive more information than just the received and
   provided energy; therefore, monitored data requires protection.  This
   protection includes authentication and authorization of entities
   requesting access to monitored data as well as confidentiality
   protection during transmission of monitored data.  Privacy of stored
   data in an entity must be taken into account.  Monitored data may be
   used as input to control, accounting, and other actions, so integrity
   of transmitted information and authentication of the origin may be
   needed.

4.  IANA Considerations

   This document has no IANA actions.

5.  Acknowledgments

   The contribution of Luis M.  Contreras to this document has been
   supported by the Smart Networks and Services Joint Undertaking (SNS
   JU) under the European Union's Horizon Europe research and innovation
   projects 6Green (Grant Agreement no. 101096925) and Exigence (Grant
   Agreement no. 101139120).










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6.  Use Cases Living List

   Consider 5g vs network slicing: 3GPP spec describing energy
   efficiency KPIs. 3GPP TS 28.554.
   Reference:https://datatracker.ietf.org/doc/rfc9543/ Connectivity from
   radio side (trying to control the traffic/related work to CCAMP)
   Marisol to add one use case: drift from data specifications...
   (somehow link to the above) Energy Metric in E2E view

7.  References

7.1.  Normative References

   [IEC.61850-7-4] International Electrotechnical Commission,
   "Communication networks and systems for power utility automation --
   Part 7-4: Basic communication structure -- Compatible logical node
   classes and data object classes", March 2010.

   [IEC.62053-21] International Electrotechnical Commission,
   "Electricity metering equipment (a.c.) -- Particular requirements --
   Part 21: Static meters for active energy (classes 1 and 2)", January
   2003.

   [IEC.62053-22] International Electrotechnical Commission,
   "Electricity metering equipment (a.c.) -- Particular requirements --
   Part 22: Static meters for active energy (classes 0,2 S and 0,5 S)",
   January 2003.

   [IEEE-100] IEEE, "The Authoritative Dictionary of IEEE Standards
   Terms, IEEE 100, Seventh Edition", December 2000.

   [IEEE-1621] Institute of Electrical and Electronics Engineers, "IEEE
   1621-2004 - IEEE Standard for User Interface Elements in Power
   Control of Electronic Devices Employed in Office/Consumer
   Environments", 2004.

   [ATIS-0600015.03.2013] ATIS, "ATIS-0600015.03.2013: Energy Efficiency
   for Telecommunication Equipment: Methodology for Measurement and
   Reporting for Router and Ethernet Switch Products", 2013.

   [ETSI-ES-203-136] ETSI, "ETSI ES 203 136: Environmental Engineering
   (EE); Measurement methods for energy efficiency of router and switch
   equipment", 2017, <https://www.etsi.org/deliver/
   etsi_es/203100_203199/203136/01.02.00_50/ es_203136v010200m.pdf>.







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   [ITUT-L.1310] ITU-T, "L.1310 : Energy efficiency metrics and
   measurement methods for telecommunication equipment", 2020,
   https://www.itu.int/rec/T-REC-L.1310/en (https://www.itu.int/rec/T-
   REC-L.1310/en).

7.2.  Informative References

   [IEC.60050] International Electrotechnical Commission, "Electropedia:
   The World's Online Electrotechnical Vocabulary", 2013,
   http://www.electropedia.org/iev/iev.nsf/welcome?openform
   (http://www.electropedia.org/iev/iev.nsf/welcome?openform).

   [ITU-M.3400] International Telecommunication Union, "ITU-T
   Recommendation M.3400 -- Series M: TMN and Network Maintenance:
   International Transmission Systems, Telephone Circuits, Telegraphy,
   Facsimile and Leased Circuits -- Telecommunications Management
   Network - TMN management functions", February 2000.

8.  Appendix

   This appendix should be removed when the initial set of GREEN WG
   documents will be stable

9.  Informative References

   [GREEN-BOF]
              "BOF proposal for GREEN WG Creation", 10 May 2024,
              <https://github.com/marisolpalmero/GREEN-bof>.

   [GREEN_NGNM]
              "NGMN Alliance, GREEN FUTURE NETWORKS: METERING IN
              VIRTUALISED RAN INFRASTRUCTURE", n.d.,
              <https://www.ngmn.org/publications/metering-in-
              virtualised-ran-infrastructure.html>.

   [legacy-path]
              "Requirements for Energy Efficiency Management", 21 July
              2024, <https://datatracker.ietf.org/doc/draft-stephan-
              legacy-path-eco-design>.

   [mWT025]   "ETSI GR mWT 025, Wireless Backhaul Network and Services
              Automation: SDN SBI YANG models, V1.1.1.", 31 March 2021.

   [ONF-MW]   "ONF TR-532, Microwave Information Model, version 2.0.",
              31 January 2024.






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   [operators-inputs]
              "Input from Operators to GREEN BoF", 20 July 2024,
              <https://datatracker.ietf.org/meeting/120/materials/
              slides-120-green-input-from-operators-to-green-bof-01>.

   [RFC8432]  Ahlberg, J., Ed., Ye, M., Ed., Li, X., Contreras, LM., and
              CJ. Bernardos, "A Framework for Management and Control of
              Microwave and Millimeter Wave Interface Parameters",
              RFC 8432, DOI 10.17487/RFC8432, October 2018,
              <https://www.rfc-editor.org/rfc/rfc8432>.

   [RFC8561]  Ahlberg, J., Ye, M., Li, X., Spreafico, D., and M.
              Vaupotic, "A YANG Data Model for Microwave Radio Link",
              RFC 8561, DOI 10.17487/RFC8561, June 2019,
              <https://www.rfc-editor.org/rfc/rfc8561>.

   [RFC9543]  Farrel, A., Ed., Drake, J., Ed., Rokui, R., Homma, S.,
              Makhijani, K., Contreras, L., and J. Tantsura, "A
              Framework for Network Slices in Networks Built from IETF
              Technologies", RFC 9543, DOI 10.17487/RFC9543, March 2024,
              <https://www.rfc-editor.org/rfc/rfc9543>.

   [sustainability-insights]
              "Sustainability Insights", 7 May 2024,
              <https://datatracker.ietf.org/doc/html/draft-almprs-
              sustainability-insights>.

   [TS23.501] "3GPP TS 23.501, System architecture for the 5G System
              (5GS), 17.6.0.", 22 September 2022.

   [TS28.554] "3GPP TS 28.554, Management and orchestration; 5G end to
              end Key Performance Indicators (KPI), 17.15.0.", 25
              September 2024.

Authors' Addresses

   Emile Stephan
   Orange
   Email: emile.stephan@orange.com


   Marisol Palmero
   Cisco Systems, Inc.
   Email: mpalmero@cisco.com


   Benoit Claise
   Huawei



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   Email: benoit.claise@huawei.com


   Qin Wu
   Huawei
   Email: bill.wu@huawei.com


   Luis M. Contreras
   Telefonica
   Email: luismiguel.contrerasmurillo@telefonica.com


   Carlos J. Bernardos
   Universidad Carlos III de Madrid
   Email: cjbc@it.uc3m.es



































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