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Network Working Group                                    J. Quittek, Ed.
Internet-Draft                                                 R. Winter
Intended status: Informational                                  T. Dietz
Expires: January 1, 2012                                 NEC Europe Ltd.
                                                               B. Claise
                                                         M. Chandramouli
                                                     Cisco Systems, Inc.
                                                           June 30, 2011


                   Requirements for Energy Management
                    draft-ietf-eman-requirements-03

Abstract

   This document defines requirements for standards specifications for
   energy management.  Defined requirements concern monitoring functions
   as well as control functions.  Covered functions include
   identification of powered entities, monitoring of their power state,
   power inlets, power outlets, actual power, consumed energy, and
   contained batteries.  Further included is control of powered
   entities' power supply and power state.  This document does not
   specify the features that must be implemented by compliant
   implementations but rather features that must be supported by
   standards for energy management.

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
   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 January 1, 2012.

Copyright Notice

   Copyright (c) 2011 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
   (http://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 Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.


Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  4
     1.1.  Conventional requirement for energy management . . . . . .  4
     1.2.  Specific requirements for energy management  . . . . . . .  5

   2.  Terminology  . . . . . . . . . . . . . . . . . . . . . . . . .  6

   3.  General Objectives of Energy Management  . . . . . . . . . . .  8
     3.1.  Power states . . . . . . . . . . . . . . . . . . . . . . .  8
     3.2.  Trade-offs . . . . . . . . . . . . . . . . . . . . . . . .  8
     3.3.  Local and network-wide energy management . . . . . . . . .  9
     3.4.  Energy monitoring  . . . . . . . . . . . . . . . . . . . .  9
     3.5.  Overview of energy management requirements . . . . . . . . 10

   4.  Identification of Powered Entities . . . . . . . . . . . . . . 10

   5.  Required Information on Powered Entities . . . . . . . . . . . 11
     5.1.  General information on entities  . . . . . . . . . . . . . 11
     5.2.  Power state  . . . . . . . . . . . . . . . . . . . . . . . 12
     5.3.  Power inlet and power outlet . . . . . . . . . . . . . . . 14
     5.4.  Power  . . . . . . . . . . . . . . . . . . . . . . . . . . 16
     5.5.  Energy . . . . . . . . . . . . . . . . . . . . . . . . . . 18
     5.6.  Battery State  . . . . . . . . . . . . . . . . . . . . . . 19

   6.  Control of Powered Entities  . . . . . . . . . . . . . . . . . 21

   7.  Reporting on Other Powered Entities  . . . . . . . . . . . . . 22

   8.  Controlling Other Powered Entities . . . . . . . . . . . . . . 23
     8.1.  Controlling power states of other entities . . . . . . . . 23
     8.2.  Controlling power supply of other entities . . . . . . . . 24

   9.  Security Considerations  . . . . . . . . . . . . . . . . . . . 25

   10. IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 26




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   11. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 26

   12. Open issues  . . . . . . . . . . . . . . . . . . . . . . . . . 26
     12.1. High/Low power notifications . . . . . . . . . . . . . . . 26
     12.2. Power and energy time series?  . . . . . . . . . . . . . . 26
     12.3. Inlet/outlet combinations  . . . . . . . . . . . . . . . . 26
     12.4. Aggregation functions  . . . . . . . . . . . . . . . . . . 27
     12.5. Add a definition of 'demand' . . . . . . . . . . . . . . . 27
     12.6. IEC references . . . . . . . . . . . . . . . . . . . . . . 27
     12.7. Standard references for BACNET or MODBUS . . . . . . . . . 27
     12.8. IEEE 1621 and 802.3az references . . . . . . . . . . . . . 27
     12.9. DC power quality covered by IEC standard?  . . . . . . . . 27

   13. Informative References . . . . . . . . . . . . . . . . . . . . 27

   Appendix A.  Existing Standards  . . . . . . . . . . . . . . . . . 28
     A.1.  Existing IETF Standards  . . . . . . . . . . . . . . . . . 29
       A.1.1.  ENTITY MIB . . . . . . . . . . . . . . . . . . . . . . 29
       A.1.2.  ENTITY STATE MIB . . . . . . . . . . . . . . . . . . . 29
       A.1.3.  ENTITY SENSOR MIB  . . . . . . . . . . . . . . . . . . 30
       A.1.4.  UPS MIB  . . . . . . . . . . . . . . . . . . . . . . . 30
       A.1.5.  POWER ETHERNET MIB . . . . . . . . . . . . . . . . . . 31
       A.1.6.  LLDP MED MIB . . . . . . . . . . . . . . . . . . . . . 31
     A.2.  Existing standards of other bodies . . . . . . . . . . . . 31
       A.2.1.  DMTF . . . . . . . . . . . . . . . . . . . . . . . . . 31
       A.2.2.  OVDA . . . . . . . . . . . . . . . . . . . . . . . . . 32
       A.2.3.  IEEE-ISTO Printer WG . . . . . . . . . . . . . . . . . 32

   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 32






















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1.  Introduction

   With rising energy cost and with an increasing awareness of the
   ecological impact of running IT and networking equipment, energy
   management is becoming an additional basic requirement for network
   management systems and frameworks.

   This document defines requirements for standards specifications for
   energy management.  Defined requirements concern monitoring functions
   as well as control functions.  Covered functions include
   identification of powered entities, monitoring of their power state,
   power inlets, power outlets, actual power, consumed energy, and
   contained batteries.  Further included is control of powered
   entities' power supply and power state.  Note that this document does
   not specify the features that must be implemented by compliant
   implementations but rather features that must be supported by
   standards for energy management.

   The main subject of energy management are powered entities that
   consume electric energy.  Powered entities include devices that have
   an IP address and can be addressed directly, such as hosts, routers,
   and middleboxes, as well as devices indirectly connected to an IP
   network, for which a proxy with an IP address provides a management
   interface, for example, devices in a building energy management
   infrastructure using BACNET or MODBUS protocols.

   The requirements specified in this document explicitly concern the
   standards specification process and not the implementation of
   specified standards.  All requirements in this document must be
   reflected by standards specifications to be developed based on these
   requirements.  But which of the features specified by these standards
   will be mandatory, recommended, or optional for compliant
   implementations is to be defined by the concrete standards track
   document(s) and not in this document.

   This document first discusses general objectives of energy management
   in Section 3.  Requirements for an energy management standard are
   specified in Sections 4 to 8.

1.1.  Conventional requirement for energy management

   The specification of requirements for an energy management standard
   starts with Section 4 addressing the identification of powered
   entities and the granularity of reporting of energy-related
   information.  A standard must support unique identification of
   powered entities.  Furthermore, it must support more than just
   reporting per powered device.  Support is required for also reporting
   energy-related information on individual components of a device or



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   subtended devices.  This is why this draft uses the more general term
   "powered entity" rather than "powered device".  An entity may be a
   device or a component of a device.

   Section 5 specifies requirements related to monitoring of powered
   entities.  This includes general (type, context) information and
   specific information on power states, power inlets, power outlets,
   power, energy, and batteries.  Control power state and power supply
   of powered entities is covered by requirements specified in
   Section 6.

1.2.  Specific requirements for energy management

   At first glance the rather conventional requirements summarized above
   seem to be all that would be needed for energy management.  But it
   turns out that there are some significant differences between energy
   management and most of the well known conventional network management
   functions.  The most significant difference from many other
   management functions is the need to report on others.  There are
   three major reasons for this.
   o  For monitoring and controlling a particular powered entity in
      general it is not sufficient to communicate with the entity only,
      but in many cases also communication with other entities along the
      power distribution path may be necessary, for example, with power
      switches and power meters.  Indeed, there are situations where a
      power or energy meter is not located in the powered entity, but in
      a different physical location.  For example, a Power Distribution
      Unit (PDU), which supplies power for a server connected to a PDU
      socket, would meter the power supplied, while the server may not
      have the capability to measure its power consumption.  A second
      example is a Power over Ethernet port, which provides power to the
      attached device, and which can meter how much power/energy it
      offers to the attached device.
   o  Energy management often extends its scope beyond entities with IP
      network interfaces, for example toward non-IP building networks,
      that are accessed via an IP gateway.  Requirements in this
      document do not fully cover all these networks, but they cover
      means for opening IP network management towards them.
   o  For monitoring of particular powered entities, it is sometimes not
      a scalable approach to communicate with all the powered entities
      directly from a central energy management system as the number of
      powered entities keeps increasing.

   This specific issue of energy management and a set of further ones
   are covered by requirements specified in Sections 7 and 8.






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2.  Terminology

2.1.  Energy

   Electric Energy is needed for operating electric entities.  These
   entities "consume" electric energy by converting it to thermal energy
   (heat) or other kinds of energy while conducting their operational
   tasks.  For energy management, the total energy converted by an
   entity during a time interval is of interest.

   The term 'energy consumption' is commonly used for both, for
   referring to the amount of consumed energy and also for referring to
   the process of consuming energy.  In the first case it addresses
   consumed energy, in the second one it addresses power, typically an
   average power.

2.2.  Power

   Power is defined as energy conversion rate.  For energy management,
   the instantaneous power of a managed entity may be of interest as
   well as the average power over a time interval.

2.3.  Powered entity

   A powered entity is a consumer of energy that is subject to energy
   management.  In general, all managed physical entities in a
   communication network consume electric energy and thus are subject to
   energy management including particularly energy monitoring and energy
   control.

   A powered entity can be a managed device or a component of a managed
   device, which is monitored individually.

2.4.  Power state

   Power state of an entity is defined as a specific settings of an
   entity that influences its power.  Examples of power states of an
   entity are on, off, hibernate, and sleep.

2.5.  Power monitor

   Energy management requires retrieving energy-related information on
   powered entities.  In many cases this information is not available at
   the entities themselves, but at other entities.  For example
   measurement of power and energy consumption can be conducted by power
   meters at other locations along the power distribution tree for the
   powered entity.




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   A power monitor is a module that reports energy-related information
   on powered entities.  A power monitor may be integrated into a
   powered entity or located remotely of the powered entity.  Instances
   of power monitors may report information on, for example, power
   supply, power, and power state of a powered entity.  There may be
   multiple power monitors reporting information on the same powered
   entity.

2.6.  Power inlet

   Powered entities receive power at their power inlets.  Powered
   entities may have multiple inlets, for example, servers with
   redundant power supply.  Examples for power inlets are AC power cords
   of an entity or an Ethernet port at which the entity receives DC
   Power over Ethernet (PoE).

2.7.  Power outlet

   Entities may have means to supply others with electrical power.
   Power is delivered to other entities through power outlets.  Power
   sourcing entities often have more than one power outlet.  Examples
   for power outlets are AC power sockets at a Power Distribution Unit
   (PDU) and Ethernet ports at a Power over Ethernet (PoE) Power
   Sourcing Equipment (PSE), that can supply entities with DC power
   using the Ethernet cable.

2.8.  Energy management

   Energy management deals with assessing and influencing the
   consumption of energy in a network of powered entities.  A typical
   objective of energy management is reducing the energy consumption in
   the network.  Ways towards achieving this objective may be limited by
   other objectives of a general network management system, such as
   service level objectives.

2.9.  Energy management standard

   This document specifies requirements for an energy management
   standard.  This term refers to a collections of documents specifying
   standards for energy-related monitoring and control.  The energy
   management standard specifies means for building energy management
   systems.

   Requirements specified in this document concern the means that an
   energy management standard must provide.  It does not imply that all
   required means must be implemented in all energy standard scenarios.
   Which means and features must be implemented by compliant
   implementations is to be specified by the energy management standard



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   itself, not by this requirements document.

   Note that for meeting individual requirements specified in this
   document not necessarily new standards are required.  It is
   recommended to rather use existing standards than specify new ones.


3.  General Objectives of Energy Management

   The basic objective of energy management is operating communication
   networks and other equipment with minimal amount of energy, while
   maintaining a certain level of service.  A set of use cases for
   energy management can be found in
   [I-D.tychon-eman-applicability-statement].

3.1.  Power states

   One approach to achieve this goal is by setting all powered entities
   to an operational state that results in lower energy consumption, but
   still meets the service level performance objectives.  The sufficient
   performance level may vary over time and can depend on several
   factors.  In principle, there are four basic types of power states
   for a powered entity or for a whole system:
   o  full power state
   o  reduced power states (lower clock rate for processor, lower data
      rate on a link, etc.)
   o  sleep (stand-by) state (not functional, but immediately available)
   o  power-off state (may imply requiring significant time for becoming
      operational)
   In actual implementations the number of power states and their
   properties vary a lot.  Very simple powered entities may just have
   only the extreme states, full power and power-off state.  Some
   implementations might use IEEE1621 model of three states on, off, and
   sleep.  However, more granular power states can be implemented with
   many levels of reduced power and/or sleep states.

3.2.  Trade-offs

   While the general objective of energy management is quite clear, the
   way to attain that goal is often difficult.  In many cases there is
   no way of reducing power consumption without the consequence of a
   potential performance, service, or capacity degradation.  Then a
   trade-off needs to be dealt with between service level objectives and
   energy efficiency.  In other cases a reduction of energy consumption
   can easily be achieved while still maintaining sufficient service
   level performance, for example, by switching powered entities to
   lower power states when higher performance is not needed.




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3.3.  Local and network-wide energy management

   Many energy saving functions can be executed locally by an entity.
   The basic principle is that an entity monitors its usage and
   dynamically adapts its energy consumption according to the required
   performance.  In the extreme case, an entity switches to a sleep
   state when it is not in use at all.  Potential interactions with an
   energy management system for such an entity include the observation
   of the entity's power state and the configuration of power saving
   policies, for example, by setting thresholds for power state changes.

   Energy savings can also be achieved with policies implemented by a
   network management system that controls power states of managed
   entities.  In order to make policy decisions properly, information
   about the energy consumption of entities in different power states is
   required.  Often this information is acquired best through
   monitoring.

   Both methods, network-wide and local energy management, have
   advantages and disadvantages.  In some cases for example, significant
   energy savings can be achieved by simply setting all entities in a
   network to sleep, when the network is not needed.  However, in
   general it is dangerous to set all entities of a group to the same
   state, because there is a risk that such actions ignore specifics of
   individual entities or violate local service level agreements.

3.4.  Energy monitoring

   It should be noted that only monitoring energy consumption and power
   states is obviously not a means to reduce the energy consumption of
   an entity.  In fact, it is likely to increase the power consumption
   of an entity slightly.  The reason is that monitoring energy requires
   instrumentation that consumes energy when in use.  And also reporting
   of measured quantities over the network consumes energy.  However,
   the acquired energy consumption and power state information is
   essential for defining energy saving policies and can be used as
   input to power state control loops that in total can lead to energy
   savings.

   Monitoring operational power states and energy consumption can also
   be useful for other energy management purposes including but not
   limited to
   o  investigating power saving potential
   o  evaluating the effectiveness of energy saving policies and
      measures
   o  deriving, implementing, and testing power management strategies





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   o  accounting for the total power consumption of a powered entity, a
      network, or a service
   o  predicting an entity's reliability based on power usage.
   o  choosing time of next maintenance cycle for an entity.

3.5.  Overview of energy management requirements

   From the considerations described above the following basic
   management functions appear to be required for energy management:
   o  monitoring power states of powered entities
   o  monitoring power (energy consumption rate) of powered entities
   o  monitoring (accumulated) energy consumption of powered entities
   o  setting power states of powered entities
   o  setting and enforcing power saving policies for individual powered
      entities as well as for networks of many powered entities

   It should be noted that active power control is complementary (but
   essential) to other energy savings measures such as low power
   electronics, energy saving protocols (for example, IEEE 802.3az), and
   energy-efficient device design (for example, sleep and low-power
   modes for individual components of a device), and energy-efficient
   network architectures.  Measurement of energy consumption may also
   provide input for developing these technologies.


4.  Identification of Powered Entities

   As already stated Section 1.1, entities on which energy-related
   information is provided are identified in a sufficiently unique way.
   This holds in particular for entities that are components of managed
   devices and in case that one entity reports information on another
   one, see Section 7.  But also for powered entities that control other
   powered entities it is important to identify the entities they
   control, see Section 8.

   Also stated already in Section 1.1 is the requirement of providing
   means for reporting energy-related information on components of a
   managed device.  An entity in this document may be an entire managed
   device or just a component of it.  Examples of components of interest
   are a hard drive, a battery, or a line card.  Also for controlling
   entities it may be useful to be able to address individual components
   in order to save energy.  For example, server blades can be switched
   off when the overall load is low or line cards at switches may be
   switched off at night times.

   Instrumentation for measuring energy consumption of a device is
   typically more expensive than instrumentation for retrieving the
   devices power state.  It may be a reasonable compromise in many cases



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   to provide power state information for all individually switchable
   components of a device separately, while the energy consumption is
   only measured for the entire device.

   Detailed Requirements:

4.1.  Identifying powered entities

   The energy management standard must provide means for uniquely
   identifying powered entities that are monitored or controlled by an
   energy management system.  Uniqueness must be given in a domain that
   is large enough to avoid collisions of identities at potential
   receivers of monitored information.

4.2.  Identifying components of powered devices

   The energy management standard must provide means for identifying not
   just entire devices as powered entities, but also individual
   components of powered devices.


5.  Required Information on Powered Entities

   This section describes energy-related information on powered entities
   for which an energy management standard must provide means for
   retrieving and reporting.

   Note that the fact that an energy management standard provides
   required means does not imply that all of them must be implemented by
   every compliant implementation.  The concrete specification of
   standards based on these requirements may label individual features
   as mandatory, recommended, or optional.

   Required information on powered entities can be structured into six
   groups.  Section 5.1 specifies requirements for general information
   on powered entities, such as type of entity or context information.
   Section 5.2 covers requirements related to entities' power states.
   Requirements for information on power inlets and power outlets of
   powered entities are specified in Section 5.3.  Monitoring of power
   and energy is covered by Sections 5.4 and 5.5, respectively.
   Finally, Section 5.6 specified requirements for monitoring batteries.

5.1.  General information on entities

   For energy management it is useful to understand role and context of
   an entity.  When monitoring, it may be helpful to group energy
   consumption per kind of entity.  When controlling and setting power
   states it may be helpful to understand the kind and role of an entity



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   in a network, for example, in order to avoid switching off vital
   network components.

   Detailed Requirements:

5.1.1.  Type of powered entity

   The energy management standard must provide means to retrieve and
   report the type of powered entities.

5.1.2.  Grouping of powered entities

   The energy management standard must provide means for grouping
   powered entities, for example, into energy monitoring domains, energy
   control domains, power supply domains, groups of entities of the same
   type, etc.

5.1.3.  Context information on powered entities

   The energy management standard must provide means for retrieving and
   reporting context information on powered entities, for example tags
   associated with an entity that indicate the entity's role, or
   importance.

5.2.  Power state

   Many entities have a limited number of discrete power states, such
   as, for example, full power, low power, standby, hibernating, and
   off.

   Obviously, there is a need to report the actual power state of an
   entity.  Beyond that, there is also a requirement for standardizing
   means for retrieving the list of all supported power states of an
   entity.

   Different standards bodies have already defined their own sets of
   power states for powered entities.  Further organizations are in the
   process of adding more of these sets.  In order to support multiple
   management systems possibly using different power state sets, while
   simultaneously interfacing with a particular entity, the energy
   management standard must provide means for supporting multiple power
   state sets used simultaneously at a powered entity.

   Some of the power states may have parameters that describe the power
   state with entity's functional capabilities and are represented
   precisely by numeric values.  For example, in low power state, a
   reduced clock rate may be set to a large number of different values.
   Since state parameters vary a lot from implementation to



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   implementation it is not considered a requirement to define standards
   for reporting all those power states parameters.  However, it would
   be useful to have standardized means for reporting some key
   parameters, such as mean power and maximum power of an entity in a
   certain state.

   There also is a need to report statistics on power states including
   the time spent an the energy consumed in a power state.

   For some network management tasks, it may be desirable to receive
   notifications from entities, for example, when the components or the
   entire entity change their power state.

   Detailed Requirements:

5.2.1.  Actual power state

   The energy management standard must provide means for reporting the
   actual power state of an entity.

5.2.2.  List of supported power states

   The energy management standard must provide means for retrieving the
   list of all potential power states of an entity.

5.2.3.  Multiple power state sets

   The energy management standard must provide means for supporting
   multiple power state sets simultaneously at a powered entity.

5.2.4.  List of supported power state sets

   The energy management standard must provide means for retrieving the
   list of all power state sets supported by an entity.

5.2.5.  List of supported power states

   Referring to the "list of supported power state sets" requirement,
   the energy management standard must provide means for retrieving the
   list of all potential power states of an entity that belong to a
   given power state set.

5.2.6.  Maximum and average power per power state

   The energy management standard must provide means for retrieving the
   maximum power and the average power as a typically static property
   for each supported power state.




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5.2.7.  Power state statistics

   The energy management standard must provide means for monitoring
   statistics per power state including at least the total time spent in
   a power state, the number of times a state was entered and the last
   time a state was entered.  More power state statistics are addressed
   by requirement 5.5.3.

5.2.8.  Power state changes

   The energy management standard must provide means for generating a
   notification when the actual power state of a powered entity changes.

5.3.  Power inlet and power outlet

   Powered entities have power inlets at which they are supplied with
   electric power.  Many entities just have a single power inlet, while
   others have multiple ones.  Often different power inlets are
   connected to separate power distribution trees.  For energy
   monitoring, it is important information which power inlets an entity
   has, if power is available at an inlet and which of them are actually
   in use.

   Some entities have power outlets for supplying other entities with
   electric power.  An entity may have multiple power outlets.  Examples
   are a Power Distribution Units (PDU) and a Power over Ethernet (PoE)
   Power Sourcing Equipment (PSE).

   For identifying and potentially controlling the source of power
   received at an inlet, it is useful to identify the power outlet of
   another entity at which the received power is provided.  Analogously,
   for each outlet it is of interest to identify the power inlets that
   receive the power provided at a certain outlet.

   Static properties of each power inlet and each power outlet are
   useful information for energy management.  Static properties include
   the kind of electric current (Alternating Current (AC) or Direct
   Current (DC)), the nominal voltage, the nominal AC frequency, and the
   number of AC phases.

   Detailed Requirements:

5.3.1.  List of power inlets and power outlets

   The energy management standard must provide means for monitoring the
   list of power inlets and power outlets at an entity.





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5.3.2.  Corresponding power outlet

   The energy management standard must provide means for identifying the
   power outlet that provides the power received at a power inlet.

5.3.3.  Corresponding power inlets

   The energy management standard must provide means for identifying the
   list of power inlets that receive the power provided at a power
   outlet.

5.3.4.  Availability of power

   The energy management standard must provide means for monitoring the
   availability of power at each power inlet and each power outlet.
   This information indicates whether at a power providing outlet power
   supply is switched on or off.

5.3.5.  Use of power

   The energy management standard must provide means for monitoring for
   each power inlet and each power outlet if it is in actual use.  For
   the inlet this means that the entity actually receives power at the
   inlet.  For the outlet this means that actually power is provided to
   one or more entities at the outlet.

5.3.6.  Type of current

   The energy management standard must provide means for reporting the
   type of current (Alternating Current (AC) or Direct Current (DC) for
   each power inlet and each power outlet of a powered entity.

5.3.7.  Nominal voltage

   The energy management standard must provide means for reporting the
   nominal voltage for each power inlet and each power outlet of a
   powered entity.

5.3.8.  Nominal AC frequency

   The energy management standard must provide means for reporting the
   nominal AC frequency for each power inlet and each power outlet of a
   powered entity.

5.3.9.  number of AC phases

   The energy management standard must provide means for reporting the
   number of AC phases for each power inlet and each power outlet of a



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   powered entity.

5.4.  Power

   Power is a quantity measured as instantaneous power or as average
   power over a time interval.  In contrast to power state values, this
   quantity may change continuously.

   Obtaining highly accurate values for power and energy may be costly.
   Often dedicated metering hardware is needed for this purpose.
   Entities without the ability to measure their power and energy
   consumption with high accuracy may just report estimated values, for
   example based on load monitoring or even just the entity type.

   Depending on how power and energy consumption values are obtained the
   confidence in the reported value and its accuracy may vary.  Entities
   reporting such values should qualify the confidence in the reported
   values and quantify the accuracy of measurements.  For reporting
   accuracy, the accuracy classes specified in IEC 62053-21
   [IEC.62053-21] and IEC 62053-22 [IEC.62053-22] should be considered.

   In addition to the plain real power value, also further properties of
   the supplied power are subject to monitoring.  In case of AC power
   supply, there are more power values beyond the real power to be
   reported including the apparent power, the reactive power, and the
   phase angle of the current or the power factor.  For both AC and DC
   power the power quality is also subject of monitoring.  Power quality
   parameters include the actual voltage, the actual frequency, the
   Total Harmonic Distortion (THD) of voltage and current, the impedance
   of an AC phase or of the DC supply.  Power quality monitoring should
   be in line with existing standards, such as [IEC.61850-7-4].

   For some network management tasks, it is required to obtain time
   series of power values (or energy consumption values).  In general
   these could be obtained in many different ways.  It should be avoided
   that such time series can only be obtained by regular polling by the
   energy management system.  Means should be provided to either push
   such values from the place they are available to the management
   system or to have them stored at the entity for a sufficiently long
   period of time such that a management system can retrieve a stored
   time series of values.

   Detailed Requirements:

5.4.1.  Real power

   The energy management standard must provide means for reporting the
   real power for each power inlet and each power outlet of a powered



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   entity.

5.4.2.  Confidence in power values

   The energy management standard must provide means for reporting the
   confidence in reported power values by indicating the way these
   values have been obtained. for example, by power measurement, by
   estimation based on performance values, or hard coding average power
   values for a powered entity.

5.4.3.  Accuracy of power and energy values

   The energy management standard must provide means for reporting the
   accuracy of reported power values.

5.4.4.  Complex power

   The energy management standard must provide means for reporting the
   complex power for each power inlet and each power outlet of a powered
   entity.  Besides the real power, at least two out of the following
   three quantities need to be reported: apparent power, reactive power,
   phase angle.  The phase angle can be substituted by the power factor.
   In case of AC power supply, means must be provided for reporting the
   complex power per phase.

5.4.5.  Actual voltage and current

   The energy management standard must provide means for reporting the
   actual voltage and actual current for each power inlet and each power
   outlet of a powered entity.  In case of AC power supply, means must
   be provided for reporting the actual voltage and actual current per
   phase.

5.4.6.  Actual AC frequency

   The energy management standard must provide means for reporting the
   actual AC frequency for each power inlet and each power outlet of a
   powered entity.

5.4.7.  Total harmonic distortion

   The energy management standard must provide means for reporting the
   Total Harmonic Distortion (THD) of voltage and current for each power
   inlet and each power outlet of a powered entity.  In case of AC power
   supply, means must be provided for reporting the THD per phase.






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5.4.8.  Power supply impedance

   The energy management standard must provide means for reporting the
   impedance of power supply for each power inlet and each power outlet
   of a powered entity.  In case of AC power supply, means must be
   provided for reporting the impedance per phase.

5.4.9.  Time series of power values

   The energy management standard must provide means for collecting time
   series of real power values for each power inlet and for each power
   outlet of an entity without requiring to regularly poll the entity
   from an energy management station.  A solution for this is that the
   concerned entity or another entity closely interacting with the
   concerned entity collect time series of power values and make them
   available via push or pull mechanisms to receivers of the
   information.

5.5.  Energy

   Monitoring of electrical energy consumed (or converted) at an entity
   can be done in various ways.  One is collecting time series of power
   values for the entity and calculating the consumed energy from these
   values. an alternative is the entity itself or another entity taking
   care of energy measurement and reporting energy consumption values
   for certain time intervals.  Time intervals of interest are the time
   from the last restart of the entity to the reporting time, the time
   from another past event to the reporting time, or the last given
   amount of time before the reporting time.

   In order to monitor energy consumption in different power states, it
   is useful if entities record their energy consumption per power state
   and report these quantities.

   For some network management tasks, it is required to obtain time
   series of energy values.  In general these could be obtained in many
   different ways.  It should be avoided that such time series can only
   be obtained by regular polling by the energy management system.
   Means should be provided to either push such values from the place
   they are available to the management system or to have them stored at
   the entity for a sufficiently long period of time such that a
   management system can retrieve a stored time series of values.

   Detailed Requirements:







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5.5.1.  Energy

   The energy management standard must provide means for reporting the
   consumed energy received at a power input or provided at a power
   outlet of an entity.  Reports must be made for a clearly specified
   time interval.

5.5.2.  Time intervals

   The energy management standard must provide means for reporting the
   consumed energy of an entity for certain time intervals.
   o  Reports must be supported for the time interval starting at the
      last restart of the entity and ending at a certain point in time,
      such as the time when a report was delivered.
   o  Reports must be supported for a sequence of consecutive non-
      overlapping time intervals of fixed size (periodic reports).
   o  Reports must be supported for a sequence of consecutive
      overlapping time intervals of fixed size (periodic reports).
   o  Reports must be supported for an interval of given length ending
      at a certain point in time, such as the time when a report was
      delivered (sliding window)

5.5.3.  Energy per power state

   The energy management standard must provide means for reporting the
   consumed energy individually for each power state.  This extends the
   requirement 5.2.7 on power state statistics.

5.5.4.  Time series of energy values

   The energy management standard must provide means for collecting time
   series of energy values for each power inlet and for each power
   outlet of an entity without requiring to regularly poll the entity
   from an energy management station.  A solution for this is that the
   concerned entity or another entity closely interacting with the
   concerned entity collect time series of energy values and make them
   available via push or pull mechanisms to receivers of the
   information.

5.6.  Battery State

   Today more and more powered entities contain batteries that supply
   them with power when disconnected from electrical power distribution
   grids.  Common examples are nomadic and mobile devices, such as
   notebook computers, netbooks, and smart phones.  The status of
   batteries in such an entity, particularly the charging status is
   typically controlled by automatic functions that act locally on the
   entity and manually by users of the entity.  In addition to this,



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   there is a need to monitor the battery status of these entities by
   network management systems.

   The management requirements discussed above in Sections 5.1 to 5.5
   concern energy-related information on entities.  Entities may be
   powered devices or components of powered devices.  Devices containing
   batteries can be modeled in two ways.  The entire device can be
   modeled as a single entity on which energy-related information is
   reported or the battery can be modeled as an individual entity for
   which energy-related information is monitored individually according
   to requirements in Sections 5.1 to 5.5.

   In both cases further information on batteries is of interest for
   energy management, such as the current charge of the battery, the
   number of completed charging cycles, the charging state of the
   battery, and further static and dynamic battery properties.  Also
   desirable is to receive notifications if the charge of a battery
   becomes very low or if a battery needs to be replaced.

   Detailed Requirements:

5.6.1.  Battery charge

   The energy management standard must provide means for reporting the
   current charge of a battery.

5.6.2.  Battery charging state

   The energy management standard must provide means for reporting the
   charging state (charged, discharged, etc.) of a battery.

5.6.3.  Battery charging cycles

   The energy management standard must provide means for reporting the
   number of completed charging cycles of a battery.

5.6.4.  Actual battery capacity

   The energy management standard must provide means for reporting the
   actual capacity of a battery.

5.6.5.  Static battery properties

   The energy management standard must provide means for reporting
   static properties of a battery, including the nominal capacity, the
   number of cells, the nominal voltage, and the battery technology.





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5.6.6.  Low battery charge notification

   The energy management standard must provide means for generating a
   notification when a the charge of a battery decreases below a given
   threshold.

5.6.7.  Battery replacement notification

   The energy management standard must provide means for generating a
   notification when the number of charging cycles of battery exceeds a
   given threshold.

5.6.8.  Multiple batteries

   The energy management standard must provide means for meeting
   requirements 5.6.1 to 5.6.7 for each individual battery contained in
   a single entity.


6.  Control of Powered Entities

   Many entities control their power state locally by self-managed
   dynamic adaptation to the environment.  But other entities without
   that capability need interfaces for a energy management system to
   control their power states in order to save energy.  Even for self-
   managed entities such interface may be useful for overruling local
   policy decisions by global ones from an energy management system.

   Power supply is typically not self-managed by powered entities.  And
   controlling power supply is typically not conducted as interaction
   between energy management system and the powered entity itself.  It
   is rather an interaction between the management system and an entity
   providing power at its power outlets.  Still, requirements for power
   state control apply accordingly to power supply control.

   Note that shutting down the power supply abruptly may have severe
   consequences for the powered entity.

   Detailed Requirements:

6.1.  Controlling power states

   The energy management standard must provide means for setting power
   states of powered entities.







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6.2.  Controlling power supply

   The energy management standard must provide means for switching power
   supply off or turning power supply on at power outlets providing
   power to one or more powered entity.


7.  Reporting on Other Powered Entities

   As already discussed in the introduction of Section 5, not all
   energy-related information may be available at the concerned powered
   entity.  Such information may be provided by other entities, such as
   a Power Distribution Unit (PDU), external power meter, or a Power
   over Ethernet (PoE) Power Sourcing Equipment (PSE).  Some of these
   entities (PDU, PSE) can also control the power provided to the other
   powered entities, while some can just report on the remote powered
   entities (external power meter).  This section covers reporting of
   information (monitoring) only.  Please see Section 8 for requirements
   on controlling other entities

   There are cases where a power supply unit switches power for several
   powered entities by turning power on or off at a single power outlet
   or where a power meter measures the accumulated power of several
   entities at a single power line.  Consequently, it should be possible
   to report that a monitored value does not relate to just a single
   powered entity, but is an accumulated value for a set of powered
   entities.  All of these entities belonging to that set need to be
   identified.

   If a powered entity has information about where energy-related
   information on itself can be retrieved, then it would be very useful
   if it has a way to communicate this information to an energy
   management system.  This applies even if the information only
   provides accumulated quantities for several powered entities.

   Detailed Requirements:

7.1.  Reports on other powered entities

   The energy management standard must provide means for an entity to
   report energy-related information on another entity.

7.2.  Identity of other entities on which is reported

   The energy management standard must provide means for reporting the
   identity of another entity on which energy-related information is
   reported.




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7.3.  Reporting quantities accumulated over multiple entities

   For entities reporting single values that are accumulated over
   multiple entities, the energy management standard must provide means
   for reporting the list of all entities from which contributions are
   included in the accumulated value.

7.4.  List of all entities on which is reported

   The energy management standard must provide means for an entity to
   report the list of all other entities on which it can report energy-
   related information.

7.5.  Content of reports on other entities

   The energy management standard must provide means for an entity to
   indicate for each other entity on which it can provide energy-related
   information which energy-related information can be provided for this
   entity.

7.6.  Indicating source of remote information

   The energy management standard must provide means for a powered
   entity to indicate another entity at which energy-related information
   on itself can be retrieved.

7.7.  Indicating source of remote information

   For a powered entity that has another entity at which energy-related
   information on itself can be retrieved, the energy management
   standard must provide means for indicating the information that is
   available at other entities per other entity.


8.  Controlling Other Powered Entities

   This section specifies requirements for controlling power states and
   power supply of powered entities by communicating not with these
   entities themselves, but with other entities that have means for
   controlling power state or power supply of others.

8.1.  Controlling power states of other entities

   Some entities may have control of power states of other entities.
   For example a gateway to a building network may have means to control
   the power state of entities in the building that do not have an IP
   interface.  For this and similar cases means are needed to make this
   control accessible to the energy management system.



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   In addition to this, it is very useful that an entity that has its
   state controlled by other entities has means to report the list of
   these other entities.

   Detailed Requirements:

8.1.1.  Control of power states of other entities

   The energy management standard must provide means for an energy
   management system to send power state control commands to entity that
   concern the power states of other entities than the one the command
   was send to.

8.1.2.  Identity of other power state controlled entities

   The energy management standard must provide means for reporting the
   identity of another entity for which the reporting entity has means
   to control the power state.

8.1.3.  List of all power state controlled entities

   The energy management standard must provide means for an entity to
   report the list of all entities for which it can control the power
   state.

8.1.4.  List of all power state controllers

   The energy management standard must provide means for an entity that
   has receives commands controlling its power state from other entities
   to report the list of all those entities.

8.2.  Controlling power supply of other entities

   Some entities may have control of the power supply of other entities,
   for example, because the other entity is supplied via a power outlet
   of the entity.  For this and similar cases means are needed to make
   this control accessible to the energy management system.

   In addition to this, it is very useful that an entity that has its
   supply controlled by other entities has means to report the list of
   these other entities.

   Detailed Requirements:

8.2.1.  Control of power supply of other entities

   The energy management standard must provide means for an energy
   management system to send power supply control commands to entity



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   that concern the power supply of other entities than the one the
   command was send to.

8.2.2.  Identity of other power supply controlled entities

   The energy management standard must provide means for reporting the
   identity of another entity for which the reporting entity has means
   to control the power supply.

8.2.3.  List of all power supply controlled entities

   The energy management standard must provide means for an entity to
   report the list of all other entities for which it can control the
   power supply.

8.2.4.  List of all power supply controllers

   The energy management standard must provide means for an entity that
   has other entities controlling its power supply to report the list of
   all those entities.


9.  Security Considerations

   The typical security threats for the management protocol for energy
   monitoring are similar to the ones specified in the SNMP security
   framework.  In other words, from an energy monitoring point of view,
   no additional security requirements have been imposed.

   Link layer discovery mechanisms need to ensure that only the trusted
   entities shall be discovered during discovery and detect/discard
   entities without a trusted relationship to be included among the
   entities for energy monitoring.

   In terms of monitoring, considering that there can be some network
   entities which shall be entitled to collect the measured data on
   behalf of other entities, then it is important to authenticate and/or
   authorize such entities.  In addition, in the case of control of
   other entities, it would be highly desirable to have some form of an
   authentication mechanism to ensure that only the designated entities
   shall control the entities within its control domain.  It should be
   possible to prevent an entity which does not have the appropriate
   authorization and authority to control or configure entities in its
   control domain/purview.  Secondly, it should be possible to prevent
   malicious entities exercising control over entities.






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10.  IANA Considerations

   This document has no actions for IANA.


11.  Acknowledgements

   The authors would like to thank Ralf Wolter for his first essay on
   this draft.  Many thanks to William Mielke and John Parello for
   helpful comments on the draft.


12.  Open issues

12.1.  High/Low power notifications

   For some network management tasks it may be desirable to receive
   notifications from entities when the power of an entity exceeds or
   falls below certain thresholds.  Do we want to make this a
   requirement?

   Proposal: added "for example" so that we don't restrict the framework
   to only this notification

12.2.  Power and energy time series?

   We have requirements for reporting of time series of power and energy
   values.  Do we need both or just one of them?  If just one, then
   which one?

12.3.  Inlet/outlet combinations

   How to model the case that an inlet or outlet changes during
   operation from one kind to the other.  An example is a battery that
   receives power at a socket at one time.  Then the socket is an inlet.
   At another time the battery provides power at the same socket.  Then
   it's an outlet.  The same holds for entities with integrated power
   generators.

   One solution would be to introduce a new kind of hybrid in/outlets.
   Another one would be to model the same socket as inlet as well as as
   outlet.  It would appear twice in the list of all inlets and outlets.
   Then received power/energy would be reported under the inlet entry
   and provided power/energy would be reported under the outlet entry.

   These would be two solutions.  What would be the concrete requirement
   behind them?




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12.4.  Aggregation functions

   Aggregation functions are not covered (yet).  Are there requirements
   on aggregation?  Which are they?

12.5.  Add a definition of 'demand'

12.6.  IEC references

   References to mentioned IEC standards are missing.  Also these
   references should be double checked.

12.7.  Standard references for BACNET or MODBUS

   Section 1 mentions BACNET or MODBUS as examples for building network
   protocols.  We need references to the standards specifications for
   these protocols.

12.8.  IEEE 1621 and 802.3az references

   A reference to the IEEE 1621 standard is missing in section 3.1 and a
   reference to IEEE 802.3az is missing in section 3.4.  The references
   should be double checked if they are well applicable in the
   respective section.

12.9.  DC power quality covered by IEC standard?

   Is there an IEC standard on DC power quality?


13.  Informative References

   [RFC1628]  Case, J., "UPS Management Information Base", RFC 1628,
              May 1994.

   [RFC3433]  Bierman, A., Romascanu, D., and K. Norseth, "Entity Sensor
              Management Information Base", RFC 3433, December 2002.

   [RFC3621]  Berger, A. and D. Romascanu, "Power Ethernet MIB",
              RFC 3621, December 2003.

   [RFC3805]  Bergman, R., Lewis, H., and I. McDonald, "Printer MIB v2",
              RFC 3805, June 2004.

   [RFC4133]  Bierman, A. and K. McCloghrie, "Entity MIB (Version 3)",
              RFC 4133, August 2005.

   [RFC4268]  Chisholm, S. and D. Perkins, "Entity State MIB", RFC 4268,



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              November 2005.

   [I-D.tychon-eman-applicability-statement]
              Tychon, E., Silver, L., and M. Chandramouli, "Energy
              Management (EMAN) Applicability Statement",
              draft-tychon-eman-applicability-statement-02 (work in
              progress), June 2011.

   [ACPI.R30b]
              Hewlett-Packard Corporation, Intel Corporation, Microsoft
              Corporation, Phoenix Corporation, and Toshiba Corporation,
              "Advanced Configuration and Power Interface Specification,
              Revision 3.0b", October 2006.

   [DMTF.DSP1027]
              Dasari (ed.), R., Davis (ed.), J., and J. Hilland (ed.),
              "Power State Management Profile", September 2008.

   [IEEE-ISTO]
              Printer Working Group, "PWG 5106.4 - PWG Power Management
              Model for Imaging Systems 1.0:", February 2011.

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

   [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", 2010.


Appendix A.  Existing Standards

   This section analyzes existing standards for energy consumption and
   power state monitoring.  It shows that there are already several
   standards that cover only some part of the requirements listed above,
   but even all together they do not cover all of the requirements for
   energy management.



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A.1.  Existing IETF Standards

   There are already RFCs available that address a subset of the
   requirements.

A.1.1.  ENTITY MIB

   The ENTITY-MIB module defined in [RFC4133] was designed to model
   physical and logical entities of a managed system.  A physical entity
   is an identifiable physical component.  A logical entity can use one
   or more physical entities.  From an energy monitoring perspective of
   a managed system, the ENTITY-MIB modeling framework can be reused and
   whenever RFC 4133 [RFC4133] has been implemented.  The
   entPhysicalIndex from entPhysicalTable can be used to identify an
   entity/component.  However, there are use cases of energy monitoring,
   where the application of the ENTITY-MIB does not seem readily
   apparent and some of those entities could be beyond the original
   scope and intent of the ENTITY-MIB.

   Consider the case of remote devices attached to the network, and the
   network device could collect the energy measurement and report on
   behalf of such attached devices.  Some of the remote devices such as
   PoE phones attached to a switch port have been considered in the
   Power-over-Ethernet MIB module [RFC3621].  However, there are many
   other devices such as a computer, which draw power from a wall outlet
   or building HVAC devices which seem to be beyond the original scope
   of the ENTITY-MIB.

   Yet another example, is smart-PDUs, which can report the energy
   consumption of the device attached to the power outlet of the PDU.
   In some cases, the device can be attached to multiple to power
   outlets.  Thus, the energy measured at multiple outlets need to be
   aggregated to determine the consumption of a single device.  From
   mapping perspective, between the PDU outlets and the device this is a
   many-to-one mapping.  It is not clear if such a many-to-one mapping
   is feasible within the ENTITY-MIB framework.

A.1.2.  ENTITY STATE MIB

   RFC 4268 [RFC4268] defines the ENTITY STATE MIB module.
   Implementations of this module provide information on entities
   including the standby status (hotStandby, coldStandby,
   providingService), the operational status (disabled, enabled,
   testing), the alarm status (underRepair, critical, major, minor,
   warning), and the usage status (idle, active, busy).  This
   information is already useful as input for policy decisions and for
   other network management tasks.  However, the number of states would
   cover only a small subset of the requirements for power state



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   monitoring and it does not provide means for energy consumption
   monitoring.  For associating the information conveyed by the ENTITY
   STATE MIB to specific components of a device, the ENTITY STATE MIB
   module makes use of the means provided by the ENTITY MIB module
   [RFC4133].  Particularly, it uses the entPhysicalIndex for
   identifying entities.

   The standby status provided by the ENTITY STATE MIB module is related
   to power states required for energy management, but the number of
   states is too restricted for meeting all energy management
   requirements.  For energy management several more power states are
   required, such as different sleep and operational states as defined
   by the Advanced Configuration and Power Interface (ACPI) [ACPI.R30b]
   or the DMTF Power State Management Profile [DMTF.DSP1027].

A.1.3.  ENTITY SENSOR MIB

   RFC 3433 [RFC3433] defines the ENTITY SENSOR MIB module.
   Implementations of this module offer a generic way to provide data
   collected by a sensor.  A sensor could be an energy consumption meter
   delivering measured values in Watt.  This could be used for reporting
   current power of an entity and its components.  Furthermore, the
   ENTITY SENSOR MIB can be used to retrieve the accuracy of the used
   power meter.

   Similar to the ENTITY STATE MIB module, the ENTITY SENSOR MIB module
   makes use of the means provided by the ENTITY MIB module [RFC4133]
   for relating provided information to components of a device.

   However, there is no unit available for reporting energy quantities,
   such as, for example, watt seconds or kilowatt hours, and the ENTITY
   SENSOR MIB module does not support reporting accuracy of measurements
   according to the IEC / ANSI accuracy classes, which are commonly in
   use for electric power and energy measurements.  The ENTITY SENSOR
   MIB modules only provides a coarse-grained method for indicating
   accuracy by stating the number of correct digits of fixed point
   values.

A.1.4.  UPS MIB

   RFC 1628 [RFC1628] defines the UPS MIB module.  Implementations of
   this module provide information on the current real power of entities
   attached to an uninterruptible power supply (UPS) device.  This
   application would require identifying which entity is attached to
   which port of the UPS device.

   UPS MIB provides information on the state of the UPS network.  The
   MIB module contains several variables that are used to identify the



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   UPS entity (name, model,..), the battery state, to characterize the
   input load to the UPS, to characterize the output from the UPS, to
   indicate the various alarm events.  The measurements of power in UPS
   MIB are in Volts, Amperes and Watts.  The units of power measurement
   are RMS volts, RMS Amperes and are not based on Entity-Sensor MIB
   [RFC3433].

A.1.5.  POWER ETHERNET MIB

   Similar to the UPS MIB, implementations of the POWER ETHERNET MIB
   module defined in RFC3621 [RFC3621] provide information on the
   current energy consumption of the entities that receive Power over
   Ethernet (PoE).  This information can be retrieved at the power
   sourcing equipment.  Analogous to the UPS MIB, it is required to
   identify which entities are attached to which port of the power
   sourcing equipment.

   The POWER ETHERNET MIB does not report power and energy consumption
   on a per port basis, but can report aggregated values for groups of
   ports.  It does not use objects of the ENTITY MIB module for
   identifying entities, although this module existed already when the
   POWER ETHERNET MIB modules was standardized.

A.1.6.  LLDP MED MIB

   The Link Layer Discovery Protocol (LLDP) defined in IEEE 802.1ab is a
   data link layer protocol used by network devices for advertising of
   their identities, capabilities, and interconnections on a LAN
   network.  The Media Endpoint Discovery (MED) (ANSI/TIA-1057) is an
   enhancement of LLDP known as LLDP-MED.  The LLDP-MED enhancements
   specifically address voice applications.  LLDP-MED covers 6 basic
   areas: capabilities discovery, LAN speed and duplex discovery,
   network policy discovery, location identification discovery,
   inventory discovery, and power discovery.

A.2.  Existing standards of other bodies

A.2.1.  DMTF

   The DMTF has defined a power state management profile [DMTF.DSP1027]
   that is targeted at computer systems.  It is based on the DMTF's
   Common Information Model (CIM) and rather an entity profile than an
   actual energy consumption monitoring standard.

   The power state management profile is used to describe and to manage
   the power state of computer systems.  This includes e.g. means to
   change the power state of an entity (e.g. to shutdown the entity)
   which is an aspect of but not sufficient for active energy



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   management.

A.2.2.  OVDA

   ODVA is an association consisting of members from industrial
   automation companies.  ODVA supports standardization of network
   technologies based on the Common Industrial Protocol (CIP).  Within
   ODVA, there is a special interest group focused on energy and
   standardization and inter-operability of energy aware entities.

A.2.3.  IEEE-ISTO Printer WG

   The charter of the IEEE-ISTO Printer Working Group is for open
   standards that define printer related protocols, that printer
   manufacturers and related software vendors shall benefit from the
   interoperability provided by conformance to these standards.  One
   particular aspect the Printer WG is focused on is power monitoring
   and management of network printers and imaging systems PWG Power
   Management Model for Imaging Systems [IEEE-ISTO].  Clearly, these
   devices are within the scope of energy management since these devices
   consume power and are attached to the network.  In addition, there is
   ample scope of power management since printers and imaging systems
   are not used that often.  IEEE-ISTO Printer working group has defined
   MIB modules for monitoring the power consumption and power state
   series that can be useful for power management of printers.  The
   energy management framework should also take into account the
   standards defined in the Printer working group.  In terms of other
   standards, IETF Printer MIB RFC3805 [RFC3805] has been standardized,
   however, this MIB module does not address power management of
   printers.


Authors' Addresses

   Juergen Quittek (editor)
   NEC Europe Ltd.
   NEC Laboratories Europe
   Network Research Division
   Kurfuersten-Anlage 36
   Heidelberg  69115
   DE

   Phone: +49 6221 4342-115
   Email: quittek@neclab.eu







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   Rolf Winter
   NEC Europe Ltd.
   NEC Laboratories Europe
   Network Research Division
   Kurfuersten-Anlage 36
   Heidelberg  69115
   DE

   Phone: +49 6221 4342-121
   Email: Rolf.Winter@neclab.eu


   Thomas Dietz
   NEC Europe Ltd.
   NEC Laboratories Europe
   Network Research Division
   Kurfuersten-Anlage 36
   Heidelberg  69115
   DE

   Phone: +49 6221 4342-128
   Email: Thomas.Dietz@neclab.eu


   Benoit Claise
   Cisco Systems, Inc.
   De Kleetlaan 6a b1
   Degem  1831
   BE

   Phone: +32 2 704 5622
   Email: bclaise@cisco.com


   Mouli Chandramouli
   Cisco Systems, Inc.
   Sarjapur Outer Ring Road
   Bangalore,
   IN

   Phone: +91 80 4426 3947
   Email: moulchan@cisco.com









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