diff options
Diffstat (limited to 'doc/rfc/rfc7326.txt')
-rw-r--r-- | doc/rfc/rfc7326.txt | 3027 |
1 files changed, 3027 insertions, 0 deletions
diff --git a/doc/rfc/rfc7326.txt b/doc/rfc/rfc7326.txt new file mode 100644 index 0000000..9271901 --- /dev/null +++ b/doc/rfc/rfc7326.txt @@ -0,0 +1,3027 @@ + + + + + + +Internet Engineering Task Force (IETF) J. Parello +Request for Comments: 7326 B. Claise +Category: Informational Cisco Systems, Inc. +ISSN: 2070-1721 B. Schoening + Independent Consultant + J. Quittek + NEC Europe Ltd. + September 2014 + + + Energy Management Framework + +Abstract + + This document defines a framework for Energy Management (EMAN) for + devices and device components within, or connected to, communication + networks. The framework presents a physical reference model and + information model. The information model consists of an Energy + Management Domain as a set of Energy Objects. Each Energy Object can + be attributed with identity, classification, and context. Energy + Objects can be monitored and controlled with respect to power, Power + State, energy, demand, Power Attributes, and battery. Additionally, + the framework models relationships and capabilities between Energy + Objects. + +Status of This Memo + + This document is not an Internet Standards Track specification; it is + published for informational purposes. + + This document is a product of the Internet Engineering Task Force + (IETF). It represents the consensus of the IETF community. It has + received public review and has been approved for publication by the + Internet Engineering Steering Group (IESG). Not all documents + approved by the IESG are a candidate for any level of Internet + Standard; see Section 2 of RFC 5741. + + Information about the current status of this document, any errata, + and how to provide feedback on it may be obtained at + http://www.rfc-editor.org/info/rfc7326. + + + + + + + + + + + +Parello, et al. Informational [Page 1] + +RFC 7326 EMAN Framework September 2014 + + +Copyright Notice + + Copyright (c) 2014 IETF Trust and the persons identified as the + document authors. All rights reserved. + + This document is subject to BCP 78 and the IETF Trust's Legal + Provisions Relating to IETF Documents + (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 ....................................................3 + 2. Terminology .....................................................4 + 3. Target Devices ..................................................9 + 4. Physical Reference Model .......................................10 + 5. Areas Not Covered by the Framework .............................11 + 6. Energy Management Abstraction ..................................12 + 6.1. Conceptual Model ..........................................12 + 6.2. Energy Object (Class) .....................................13 + 6.3. Energy Object Attributes ..................................15 + 6.4. Measurements ..............................................18 + 6.5. Control ...................................................19 + 6.6. Relationships .............................................25 + 7. Energy Management Information Model ............................29 + 8. Modeling Relationships between Devices .........................33 + 8.1. Power Source Relationship .................................33 + 8.2. Metering Relationship .....................................37 + 8.3. Aggregation Relationship ..................................38 + 9. Relationship to Other Standards ................................39 + 10. Security Considerations .......................................39 + 10.1. Security Considerations for SNMP .........................40 + 11. IANA Considerations ...........................................41 + 11.1. IANA Registration of New Power State Sets ................41 + 11.2. Updating the Registration of Existing Power State Sets ...42 + 12. References ....................................................43 + 12.1. Normative References .....................................43 + 12.2. Informative References ...................................44 + 13. Acknowledgments ...............................................45 + Appendix A. Information Model Listing .............................46 + + + + + + +Parello, et al. Informational [Page 2] + +RFC 7326 EMAN Framework September 2014 + + +1. Introduction + + Network Management is often divided into the five main areas defined + in the ISO Telecommunications Management Network model: Fault, + Configuration, Accounting, Performance, and Security Management + (FCAPS) [X.700]. Not covered by this traditional management model is + Energy Management, which is rapidly becoming a critical area of + concern worldwide, as seen in [ISO50001]. + + This document defines an Energy Management framework for devices + within, or connected to, communication networks, per the Energy + Management requirements specified in [RFC6988]. The devices, or the + components of these devices (such as line cards, fans, and disks), + can then be monitored and controlled. Monitoring includes measuring + power, energy, demand, and attributes of power. Energy Control can + be performed by setting a device's or component's state. The devices + monitored by this framework can be either of the following: + + o consumers of energy (such as routers and computer systems) and + components of such devices (such as line cards, fans, and disks) + + o producers of energy (like an uninterruptible power supply or + renewable energy system) and their associated components (such as + battery cells, inverters, or photovoltaic panels) + + This framework further describes how to identify, classify, and + provide context for such devices. While context information is not + specific to Energy Management, some context attributes are specified + in the framework, addressing the following use cases: + + o How important is a device in terms of its business impact? + + o How should devices be grouped for reporting and searching? + + o How should a device role be described? + + Guidelines for using context for Energy Management are described. + + The framework introduces the concept of a Power Interface that is + analogous to a network interface. A Power Interface is defined as an + interconnection among devices where energy can be provided, received, + or both. + + The most basic example of Energy Management is a single device + reporting information about itself. In many cases, however, energy + is not measured by the device itself but is measured upstream in the + power distribution tree. For example, a Power Distribution Unit + (PDU) may measure the energy it supplies to attached devices and + + + +Parello, et al. Informational [Page 3] + +RFC 7326 EMAN Framework September 2014 + + + report this to an Energy Management System. Therefore, devices often + have relationships to other devices or components in the power + network. An Energy Management System (EnMS) generally requires an + understanding of the power topology (who provides power to whom), the + Metering topology (who meters whom), and the potential Aggregation + (who aggregates values of others). + + The relationships build on the Power Interface concept. The + different relationships among devices and components, as specified in + this document, include power source, Metering, and Aggregation + Relationships. + + The framework does not cover non-electrical equipment, nor does it + cover energy procurement and manufacturing. + +2. Terminology + + The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", + "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this + document are to be interpreted as described in RFC 2119 [RFC2119]. + + In this document, these words will appear with the above + interpretation only when in ALL CAPS. Lowercase uses of these words + are not to be interpreted as carrying the significance of RFC 2119 + key words. + + In this section, some terms have a NOTE that is not part of the + definition itself but accounts for differences between terminologies + of different standards organizations or further clarifies the + definition. + + The terms are listed in an order that aids in reading where terms may + build off a previous term, as opposed to an alphabetical ordering. + Some terms that are common in electrical engineering or that describe + common physical items use a lowercase notation. + + Energy Management + Energy Management is a set of functions for measuring, modeling, + planning, and optimizing networks to ensure that the network and + network-attached devices use energy efficiently and appropriately + for the nature of the application and the cost constraints of the + organization. + + Reference: Adapted from [TMN]. + + + + + + + +Parello, et al. Informational [Page 4] + +RFC 7326 EMAN Framework September 2014 + + + NOTES: + + 1. "Energy Management" refers to the activities, methods, + procedures, and tools that pertain to measuring, modeling, + planning, controlling, and optimizing the use of energy in + networked systems [NMF]. + + 2. Energy Management is a management domain that is congruent to + any of the FCAPS areas of management in the ISO/OSI Network + Management Model [TMN]. Energy Management for communication + networks and attached devices is a subset or part of an + organization's greater Energy Management Policies. + + Energy Management System (EnMS) + An Energy Management System is a combination of hardware and + software used to administer a network, with the primary purpose of + Energy Management. + + NOTES: + + 1. An Energy Management System according to [ISO50001] (ISO-EnMS) + is a set of systems or procedures upon which organizations can + develop and implement an energy policy, set targets and action + plans, and take into account legal requirements related to + energy use. An ISO-EnMS allows organizations to improve energy + performance and demonstrate conformity to requirements, + standards, and/or legal requirements. + + 2. Example ISO-EnMS: Company A defines a set of policies and + procedures indicating that there should exist multiple + computerized systems that will poll energy measurements from + their meters and pricing / source data from their local + utility. Company A specifies that their CFO (Chief Financial + Officer) should collect information and summarize it quarterly + to be sent to an accounting firm to produce carbon accounting + reporting as required by their local government. + + 3. For the purposes of EMAN, the definition herein is the + preferred meaning of an EnMS. The definition from [ISO50001] + can be referred to as an ISO Energy Management System + (ISO-EnMS). + + Energy Monitoring + Energy Monitoring is a part of Energy Management that deals with + collecting or reading information from devices to aid in Energy + Management. + + + + + +Parello, et al. Informational [Page 5] + +RFC 7326 EMAN Framework September 2014 + + + Energy Control + Energy Control is a part of Energy Management that deals with + directing influence over devices. + + electrical equipment + This is a general term that includes materials, fittings, devices, + appliances, fixtures, apparatus, machines, etc., that are used as + a part of, or in connection with, an electric installation. + + Reference: [IEEE100]. + + non-electrical equipment (mechanical equipment) + This is a general term that includes materials, fittings, devices, + appliances, fixtures, apparatus, machines, etc., that are used as + a part of, or in connection with, non-electrical power + installations. + + Reference: Adapted from [IEEE100]. + + device + A device is a piece of electrical or non-electrical equipment. + + Reference: Adapted from [IEEE100]. + + component + A component is a part of electrical or non-electrical equipment + (device). + + Reference: Adapted from [TMN]. + + power inlet + A power inlet (or simply "inlet") is an interface at which a + device or component receives energy from another device or + component. + + power outlet + A power outlet (or simply "outlet") is an interface at which a + device or component provides energy to another device or + component. + + energy + Energy is that which does work or is capable of doing work. As + used by electric utilities, it is generally a reference to + electrical energy and is measured in kilowatt-hours (kWh). + + Reference: [IEEE100]. + + + + + +Parello, et al. Informational [Page 6] + +RFC 7326 EMAN Framework September 2014 + + + NOTE: + + 1. Energy is the capacity of a system to produce external activity + or perform work [ISO50001]. + + power + Power is the time rate at which energy is emitted, transferred, or + received; power is usually expressed in watts (joules per second). + + Reference: [IEEE100]. + + demand + Demand is the average value of power or a related quantity over a + specified interval of time. Note: Demand is expressed in + kilowatts, kilovolt-amperes, kilovars, or other suitable units. + + Reference: [IEEE100]. + + NOTE: + + 1. While IEEE100 defines demand in kilo measurements, for EMAN we + use watts with any suitable metric prefix. + + provide energy + A device (or component) "provides" energy to another device if + there is an energy flow from this device to the other one. + + receive energy + A device (or component) "receives" energy from another device if + there is an energy flow from the other device to this one. + + meter (energy meter) + A meter is a device intended to measure electrical energy by + integrating power with respect to time. + + Reference: Adapted from [IEC60050]. + + battery + A battery is one or more cells (consisting of an assembly of + electrodes, electrolyte, container, terminals, and (usually) + separators) that are a source and/or store of electric energy. + + Reference: Adapted from [IEC60050]. + + Power Interface + A Power Interface is a power inlet, outlet, or both. + + + + + +Parello, et al. Informational [Page 7] + +RFC 7326 EMAN Framework September 2014 + + + Nameplate Power + The Nameplate Power is the nominal power of a device as specified + by the device manufacturer. + + Power Attributes + Power Attributes are measurements of the electrical current, + voltage, phase, and frequencies at a given point in an electrical + power system. + + Reference: Adapted from [IEC60050]. + + NOTE: + + 1. Power Attributes are not intended to provide any bounds or + recommended range for the value. They are simply the reading + of the value associated with the attribute in question. + + Power Quality + "Power Quality" refers to characteristics of the electrical + current, voltage, phase, and frequencies at a given point in an + electric power system, evaluated against a set of reference + technical parameters. These parameters might, in some cases, + relate to the compatibility between electricity supplied in an + electric power system and the loads connected to that electric + power system. + + Reference: [IEC60050]. + + NOTE: + + 1. Electrical characteristics representing Power Quality + information are typically required by customer facility Energy + Management Systems. Electrical characteristics are not + intended to satisfy the detailed requirements of Power Quality + monitoring. Standards typically also give ranges of allowed + values; the information attributes are the raw measurements, + not the "yes/no" determination by the various standards. + + Reference: [ASHRAE-201]. + + + + + + + + + + + + +Parello, et al. Informational [Page 8] + +RFC 7326 EMAN Framework September 2014 + + + Power State + A Power State is a condition or mode of a device (or component) + that broadly characterizes its capabilities, power, and + responsiveness to input. + + Reference: Adapted from [IEEE1621]. + + Power State Set + A Power State Set is a collection of Power States that comprises a + named or logical control grouping. + +3. Target Devices + + With Energy Management, there exists a wide variety of devices that + may be contained in the same deployment as a communication network + but comprise a separate facility, home, or power distribution + network. + + Energy Management has special challenges because a power distribution + network supplies energy to devices and components, while a separate + communications network monitors and controls the power distribution + network. + + The target devices for Energy Management are all devices that can be + monitored or controlled (directly or indirectly) by an Energy + Management System (EnMS). These target devices include, for example: + + o Simple electrical appliances and fixtures + + o Hosts, such as a PC, a server, or a printer + + o Switches, routers, base stations, and other network equipment such + as middleboxes + + o Components within devices, e.g., a line card inside a switch + + o Batteries functioning as a device or component that is a store of + energy + + o Devices or components that charge or produce energy, such as solar + cells, charging stations, or generators + + o Power over Ethernet (PoE) endpoints + + o Power Distribution Units (PDUs) + + o Protocol gateway devices for Building Management Systems (BMS) + + + + +Parello, et al. Informational [Page 9] + +RFC 7326 EMAN Framework September 2014 + + + o Electrical meters + + o Sensor controllers with subtended sensors + + Target devices include devices that communicate via the Internet + Protocol (IP) as well as devices using other means for communication. + The latter are managed through gateways or proxies that can + communicate using IP. + +4. Physical Reference Model + + The following reference model describes physical power topologies + that exist in parallel with a communication topology. While many + more topologies can be created with a combination of devices, the + following are some basic ones that show how Energy Management + topologies differ from Network Management topologies. + + NOTE: "###" is used to denote a transfer of energy. + "- >" is used to denote a transfer of information. + + Basic Energy Management: + + +--------------------------+ + | Energy Management System | + +--------------------------+ + ^ ^ + monitoring | | control + v v + +---------+ + | device | + +---------+ + + + Basic Power Supply: + + +-----------------------------------------+ + | Energy Management System | + +-----------------------------------------+ + ^ ^ ^ ^ + monitoring | | control monitoring | | control + v v v v + +--------------+ +-----------------+ + | power source |########| device | + +--------------+ +-----------------+ + + + + + + + +Parello, et al. Informational [Page 10] + +RFC 7326 EMAN Framework September 2014 + + + Single Power Supply with Multiple Devices: + + +---------------------------------------+ + | Energy Management System | + +---------------------------------------+ + ^ ^ ^ ^ + monitoring | | control monitoring | | control + v v v v + +--------+ +------------------+ + | power |########| device 1 | + | source | # +------------------+-+ + +--------+ #######| device 2 | + # +------------------+-+ + #######| device 3 | + +------------------+ + + + Multiple Power Supplies with Single Device: + + +----------------------------------------------+ + | Energy Management System | + +----------------------------------------------+ + ^ ^ ^ ^ ^ ^ + mon. | | ctrl. mon. | | ctrl. mon. | | ctrl. + v v v v v v + +----------+ +----------+ +----------+ + | power |######| device |######| power | + | source 1 | | | | source 2 | + +----------+ +----------+ +----------+ + +5. Areas Not Covered by the Framework + + While this framework is intended as a framework for Energy Management + in general, there are some areas that are not covered. + + Non-Electrical Equipment + + The primary focus of this framework is the management of + electrical equipment. Non-electrical equipment, which is not + covered in this framework, could nevertheless be modeled by + providing interfaces that comply with the framework: for example, + using the same units for power and energy. Therefore, + non-electrical equipment that does not "convert to" or + "present as" an entity equivalent to electrical equipment is not + addressed. + + + + + + +Parello, et al. Informational [Page 11] + +RFC 7326 EMAN Framework September 2014 + + + Energy Procurement and Manufacturing + + While an EnMS may be a central point for corporate reporting, cost + computation, environmental impact analysis, and regulatory + compliance reporting, Energy Management in this framework excludes + energy procurement and the environmental impact of energy use. + + As such, the framework does not include: + + o Cost in currency or environmental units of manufacturing a + device + + o Embedded carbon or environmental equivalences of a device + + o Cost in currency or environmental impact to dismantle or + recycle a device + + o Supply chain analysis of energy sources for device deployment + + o Conversion of the usage or production of energy to units + expressed from the source of that energy (such as the + greenhouse gas emissions associated with the transfer of energy + from a diesel source) + +6. Energy Management Abstraction + + This section describes a conceptual model of information that can be + used for Energy Management. The classes and categories of attributes + in the model are described, with a rationale for each. + +6.1. Conceptual Model + + This section describes an information model that addresses issues + specific to Energy Management and complements existing Network + Management models. + + An information model for Energy Management will need to describe a + means to monitor and control devices and components. The model will + also need to describe the relationships among, and connections + between, devices and components. + + This section defines a conceptual model for devices and components + that is similar to the model used in Network Management: devices, + components, and interfaces. This section then defines the additional + attributes specific to Energy Management for those entities that are + not available in existing Network Management models. + + + + + +Parello, et al. Informational [Page 12] + +RFC 7326 EMAN Framework September 2014 + + + For modeling the devices and components, this section describes three + classes denoted by a "(Class)" suffix: a Device (Class), a Component + (Class), and a Power Interface (Class). These classes are sub-types + of an abstract Energy Object (Class). + + Summary of Notation for Modeling Physical Equipment + + Physical Modeling (Metadata) Model Instance + --------------------------------------------------------- + equipment Energy Object (Class) Energy Object + + device Device (Class) Device + + component Component (Class) Component + + inlet/outlet Power Interface (Class) Power Interface + + This section then describes the attributes of an Energy Object + (Class) for identification, classification, context, control, power, + and energy. + + Since the interconnections between devices and components for Energy + Management may have no relation to the interconnections for Network + Management, the Energy Object (Classes) contain a separate + Relationships (Class) as an attribute to model these types of + interconnections. + + The next sections describe each of the classes and categories of + attributes in the information model. + + Not all of the attributes are mandatory for implementations. + Specifications describing implementations of the information model in + this framework need to be explicit about which are mandatory and + which are optional to implement. + + The formal definitions of the classes and attributes are specified in + Section 7. + +6.2. Energy Object (Class) + + An Energy Object (Class) represents a piece of equipment that is + part of, or attached to, a communications network that is monitored + or controlled or that aids in the management of another device for + Energy Management. + + + + + + + +Parello, et al. Informational [Page 13] + +RFC 7326 EMAN Framework September 2014 + + + The Energy Object (Class) is an abstract class that contains the base + attributes to represent a piece of equipment for Energy Management. + There are three types of Energy Object (Class): Device (Class), + Component (Class), and Power Interface (Class). + +6.2.1. Device (Class) + + The Device (Class) is a subclass of Energy Object (Class) that + represents a physical piece of equipment. + + A Device (Class) instance represents a device that is a consumer, + producer, meter, distributor, or store of energy. + + A Device (Class) instance may represent a physical device that + contains other components. + +6.2.2. Component (Class) + + The Component (Class) is a subclass of Energy Object (Class) that + represents a part of a physical piece of equipment. + +6.2.3. Power Interface (Class) + + A Power Interface (Class) represents the interconnections (inlet, + outlet) among devices or components where energy can be provided, + received, or both. + + The Power Interface (Class) is a subclass of Energy Object (Class) + that represents a physical inlet or outlet. + + There are some similarities between Power Interfaces and network + interfaces. A network interface can be set to different states, such + as sending or receiving data on an attached line. Similarly, a Power + Interface can be receiving or providing energy. + + A Power Interface (Class) instance can represent (physically) an AC + power socket, an AC power cord attached to a device, or an 8P8C + (RJ45) PoE socket, etc. + + + + + + + + + + + + + +Parello, et al. Informational [Page 14] + +RFC 7326 EMAN Framework September 2014 + + +6.3. Energy Object Attributes + + This section describes categories of attributes for an Energy Object + (Class). + +6.3.1. Identification + + A Universally Unique Identifier (UUID) [RFC4122] is used to uniquely + and persistently identify an Energy Object. + + Every Energy Object has an optional unique human-readable printable + name. Possible naming conventions are textual DNS name, Media Access + Control (MAC) address of the device, interface ifName, or a text + string uniquely identifying the Energy Object. As an example, in + the case of IP phones, the Energy Object name can be the device's + DNS name. + + Additionally, an alternate key is provided to allow an Energy Object + to be optionally linked with models in different systems. + +6.3.2. Context: General + + In order to aid in reporting and in differentiation between Energy + Objects, each object optionally contains information establishing its + business, site, or organizational context within a deployment. + + The Energy Object (Class) contains a category attribute that broadly + describes how an instance is used in a deployment. The category + indicates whether the Energy Object is primarily functioning as a + consumer, producer, meter, distributor, or store of energy. + + Given the category and context of an object, an EnMS can summarize or + analyze measurements for the site. + +6.3.3. Context: Importance + + An Energy Object can provide an importance value in the range of 1 to + 100 to help rank a device's use or relative value to the site. The + importance range is from 1 (least important) to 100 (most important). + The default importance value is 1. + + For example, a typical office environment has several types of + phones, which can be rated according to their business impact. A + public desk phone has a lower importance (for example, 10) than a + business-critical emergency phone (for example, 100). As another + example, a company can consider that a PC and a phone for a customer + service engineer are more important than a PC and a phone for + lobby use. + + + +Parello, et al. Informational [Page 15] + +RFC 7326 EMAN Framework September 2014 + + + Although EnMS and administrators can establish their own ranking, the + following example is a broad recommendation for commercial + deployments [CISCO-EW]: + + 90 to 100 Emergency response + 80 to 90 Executive or business-critical + 70 to 79 General or average + 60 to 69 Staff or support + 40 to 59 Public or guest + 1 to 39 Decorative or hospitality + +6.3.4. Context: Keywords + + The Energy Object (Class) contains an attribute with context + keywords. + + An Energy Object can provide a set of keywords that is a list of tags + that can be used for grouping, summary reporting (within or between + Energy Management Domains), and searching. Potential examples are + IT, lobby, HumanResources, Accounting, StoreRoom, CustomerSpace, + router, phone, floor2, or SoftwareLab. + + The specifics of how this tag is represented are left to the MIB + module or other object definition documents to be based on this + framework. + + There is no default value for a keyword. Multiple keywords can be + assigned to an Energy Object. + +6.3.5. Context: Role + + The Energy Object (Class) contains a role attribute. The "role + description" string indicates the primary purpose the Energy Object + serves in the deployment. This could be a string representing the + purpose the Energy Object fulfills in the deployment. + + The specifics of how this tag is represented are left to the MIB + module or other object definition documents to be based on this + framework. + + Administrators can define any naming scheme for the role. As + guidance, a two-word role that combines the service the Energy Object + provides, along with type, can be used [IPENERGY]. + + Example types of devices: Router, Switch, Light, Phone, WorkStation, + Server, Display, Kiosk, HVAC. + + + + + +Parello, et al. Informational [Page 16] + +RFC 7326 EMAN Framework September 2014 + + + Example Services by Line of Business: + + Line of Business Service + ------------------------------------------------------ + Education Student, Faculty, Administration, + Athletic + + Finance Trader, Teller, Fulfillment + + Manufacturing Assembly, Control, Shipping + + Retail Advertising, Cashier + + Support Helpdesk, Management + + Medical Patient, Administration, Billing + + Role as a two-word string: "Faculty Desktop", "Teller Phone", + "Shipping HVAC", "Advertising Display", "Helpdesk Kiosk", + "Administration Switch". + + The specifics of how this tag is represented are left to the MIB + module or other object definition documents to be based on this + framework. + +6.3.6. Context: Domain + + The Energy Object (Class) contains a string attribute to indicate + membership in an Energy Management Domain. An Energy Management + Domain can be any collection of Energy Objects in a deployment, but + it is recommended to map 1:1 with a metered or sub-metered portion of + the site. + + In building management, a meter refers to the meter provided by the + utility used for billing and measuring power to an entire building or + unit within a building. A sub-meter refers to a customer- or user- + installed meter that is not used by the utility to bill but is + instead used to get measurements from portions of a building. + + The specifics of how this tag is represented are left to the MIB + module or other object definition documents to be based on this + framework. + + An Energy Object MUST be a member of a single Energy Management + Domain; therefore, one attribute is provided. + + + + + + +Parello, et al. Informational [Page 17] + +RFC 7326 EMAN Framework September 2014 + + +6.4. Measurements + + The Energy Object (Class) contains attributes to describe power, + energy, and demand measurements. + + An analogy for understanding power versus energy measurements can be + made to speed and distance in automobiles. Just as a speedometer + indicates the rate of change of distance (speed), a power measurement + indicates the rate of transfer of energy. The odometer in an + automobile measures the cumulative distance traveled; similarly, an + energy measurement indicates the accumulated energy transferred. + + Demand measurements are averages of power measurements over time. + So, using the same analogy to an automobile: measuring the average + vehicle speed over multiple intervals of time for a given distance + traveled, demand is the average power measured over multiple time + intervals for a given energy value. + + Within this framework, energy will only be quantified in units of + watt-hours. Physical devices measuring energy in other units must + convert values to watt-hours or be represented by Energy Objects that + convert to watt-hours. + +6.4.1. Measurements: Power + + The Energy Object (Class) contains a Nameplate Power Attribute that + describes the nominal power as specified by the manufacturer of the + device. The EnMS can use the Nameplate Power for provisioning, + capacity planning, and (potentially) billing. + + The Energy Object (Class) has attributes that describe the present + power information, along with how that measurement was obtained or + derived (e.g., actual, estimated, or static). + + A power measurement is qualified with the units, magnitude, and + direction of power flow and is qualified as to the means by which the + measurement was made. + + Power measurement magnitude conforms to the [IEC61850] definition of + unit multiplier for the SI (System International) units of measure. + Measured values are represented in SI units obtained by BaseValue * + (10 ^ Scale). For example, if current power usage of an Energy + Object is 17, it could be 17 W, 17 mW, 17 kW, or 17 MW, depending on + the value of the scaling factor. 17 W implies that BaseValue = 17 + and Scale = 0, whereas 17 mW implies that BaseValue = 17 and + ScaleFactor = -3. + + + + + +Parello, et al. Informational [Page 18] + +RFC 7326 EMAN Framework September 2014 + + + An Energy Object (Class) indicates how the power measurement was + obtained with a caliber and accuracy attribute that indicates: + + o Whether the measurements were made at the device itself or at a + remote source. + + o Description of the method that was used to measure the power and + whether this method can distinguish actual or estimated values. + + o Accuracy for actual measured values. + +6.4.2. Measurements: Power Attributes + + The Energy Object (Class) contains an optional attribute that + describes Power Attribute information reflecting the electrical + characteristics of the measurement. These Power Attributes adhere to + the [IEC61850-7-2] standard for describing AC measurements. + +6.4.3. Measurements: Energy + + The Energy Object (Class) contains optional attributes that represent + the energy used, received, produced, and/or stored. Typically, only + devices or components that can measure actual power will have the + ability to measure energy. + +6.4.4. Measurements: Demand + + The Energy Object (Class) contains optional attributes that represent + demand information over time. Typically, only devices or components + that can report actual power are capable of measuring demand. + +6.5. Control + + The Energy Object (Class) contains a Power State Set (Class) + attribute that represents the set of Power States a device or + component supports. + + A Power State describes a condition or mode of a device or component. + While Power States are typically used for control, they may be used + for monitoring only. + + A device or component is expected to support at least one set of + Power States consisting of at least two states: an on state and an + off state. + + There are many existing standards describing device and component + Power States. The framework supports modeling a mixed set of Power + States defined in different standards. A basic example is given by + + + +Parello, et al. Informational [Page 19] + +RFC 7326 EMAN Framework September 2014 + + + the three Power States defined in IEEE1621 [IEEE1621]: on, off, and + sleep. The Distributed Management Task Force (DMTF) standards + organization [DMTF], Advanced Configuration and Power Interface + (ACPI) specification [ACPI], and Printer Working Group (PWG) all + define larger numbers of Power States. + + The semantics of a Power State are specified by: + + a) The functionality provided by an Energy Object in this state. + + b) A limitation of the power that an Energy Object uses in this + state. + + c) A combination of a) and b). + + The semantics of a Power State should be clearly defined. Limitation + (curtailment) of the power used by an Energy Object in a state may be + specified by: + + o An absolute power value. + + o A percentage value of power relative to the Energy Object's + Nameplate Power. + + o An indication of power relative to another Power State. For + example, specify that power in state A is less than in state B. + + o For supporting Power State management, an Energy Object provides + statistics on Power States, including the time an Energy Object + spent in a certain Power State and the number of times an Energy + Object entered a Power State. + + When requesting an Energy Object to enter a Power State, an + indication of the Power State's name or number can be used. + Optionally, an absolute or percentage of Nameplate Power can be + provided to allow the Energy Object to transition to a nearest or + equivalent Power State. + + When an Energy Object is set to a particular Power State, the + represented device or component may be busy. The Energy Object + should set the desired Power State and then update the actual Power + State when the device or component changes. There are then two Power + State (Class) control attributes: actual and requested. + + The following sections describe well-known Power States for devices + and components that should be modeled in the information model. + + + + + +Parello, et al. Informational [Page 20] + +RFC 7326 EMAN Framework September 2014 + + +6.5.1. Power State Sets + + There are several standards and implementations of Power State Sets. + The Energy Object (Class) supports modeling one or multiple Power + State Set implementations on the device or component concurrently. + + There are currently three Power State Sets specified by IANA: + + IEEE1621 (256) - [IEEE1621] + DMTF (512) - [DMTF] + EMAN (768) - [RFC7326] + + The respective specific states related to each Power State Set are + specified in the following sections. The guidelines for the + modification of Power State Sets are specified in the IANA + Considerations section. + +6.5.2. Power State Set: IEEE1621 + + The IEEE1621 Power State Set [IEEE1621] consists of three rudimentary + states: on, off, or sleep. + + In IEEE1621, devices are limited to the three basic Power States -- + on (2), sleep (1), and off (0). Any additional Power States are + variants of one of the basic states, rather than a fourth state + [IEEE1621]. + +6.5.3. Power State Set: DMTF + + The DMTF [DMTF] standards organization has defined a power profile + standard based on the CIM (Common Information Model), which consists + of 15 Power States. + + The DMTF standard is targeted for hosts and computers. Details of + the semantics of each Power State within the DMTF Power State Set can + be obtained from the DMTF Power State Management Profile + specification [DMTF]. + + + + + + + + + + + + + + +Parello, et al. Informational [Page 21] + +RFC 7326 EMAN Framework September 2014 + + + The DMTF power profile extends ACPI Power States. The following + table provides a mapping between DMTF and ACPI Power State Sets: + + DMTF ACPI + ------------------------------------------------ + Reserved (0) + Reserved (1) + ON (2) G0/S0 + Sleep-Light (3) G1/S1 G1/S2 + Sleep-Deep (4) G1/S3 + Power Cycle (Off-Soft) (5) G2/S5 + Off-Hard (6) G3 + Hibernate (Off-Soft) (7) G1/S4 + Off-Soft (8) G2/S5 + Power Cycle (Off-Hard) (9) G3 + Master Bus Reset (10) G2/S5 + Diagnostic Interrupt (11) G2/S5 + Off-Soft Graceful (12) G2/S5 + Off-Hard Graceful (13) G3 + MasterBus Reset Graceful (14) G2/S5 + Power Cycle Off-Soft Graceful (15) G2/S5 + Power Cycle Off-Hard Graceful (16) G3 + +6.5.4. Power State Set: IETF EMAN + + The EMAN Power States are an expansion of the basic Power States as + defined in [IEEE1621] plus the addition of the Power States defined + in [ACPI] and [DMTF]. Therefore, in addition to the non-operational + states as defined in [ACPI] and [DMTF] standards, several + intermediate operational states have been defined. + + Physical devices and components are expected to support the EMAN + Power State Set or to be modeled via an Energy Object the supports + these states. + + An Energy Object may implement fewer or more Power States than a + particular EMAN Power State Set specifies. In that case, the Energy + Object implementation can determine its own mapping to the predefined + EMAN Power States within the EMAN Power State Set. + + There are twelve EMAN Power States that expand on [IEEE1621]. The + expanded list of Power States is derived from [CISCO-EW] and is + divided into six operational states and six non-operational states. + + + + + + + + +Parello, et al. Informational [Page 22] + +RFC 7326 EMAN Framework September 2014 + + + The lowest non-operational state is 0, and the highest is 5. Each + non-operational state corresponds to an [ACPI] Global and System + state between G3 (hard-off) and G1 (sleeping). Each operational + state represents a performance state and may be mapped to [ACPI] + states P0 (maximum performance power) through P5 (minimum performance + and minimum power). + + In each of the non-operational states (from mechoff(0) to ready(5)), + the Power State preceding it is expected to have a lower Power value + and a longer delay in returning to an operational state: + + mechoff(0): An off state where no Energy Object features are + available. The Energy Object is unavailable. No energy is + being consumed, and the power connector can be removed. + + softoff(1): Similar to mechoff(0), but some components remain + powered or receive trace power so that the Energy Object can be + awakened from its off state. In softoff(1), no context is + saved, and the device typically requires a complete boot when + awakened. + + hibernate(2): No Energy Object features are available. The Energy + Object may be awakened without requiring a complete boot, but + the time for availability is longer than sleep(3). An example + for state hibernate(2) is a save-to-disk state where DRAM + context is not maintained. Typically, energy consumption is + zero or close to zero. + + sleep(3): No Energy Object features are available, except for + out-of-band management, such as wake-up mechanisms. The time + for availability is longer than standby(4). An example for + state sleep(3) is a save-to-RAM state, where DRAM context is + maintained. Typically, energy consumption is close to zero. + + standby(4): No Energy Object features are available, except for + out-of-band management, such as wake-up mechanisms. This mode + is analogous to cold-standby. The time for availability is + longer than ready(5). For example, processor context may not + be maintained. Typically, energy consumption is close to zero. + + ready(5): No Energy Object features are available, except for + out-of-band management, such as wake-up mechanisms. This mode + is analogous to hot-standby. The Energy Object can be quickly + transitioned into an operational state. For example, + processors are not executing, but processor context is + maintained. + + + + + +Parello, et al. Informational [Page 23] + +RFC 7326 EMAN Framework September 2014 + + + lowMinus(6): Indicates that some Energy Object features may not be + available and the Energy Object has taken measures or selected + options to use less energy than low(7). + + low(7): Indicates that some Energy Object features may not be + available and the Energy Object has taken measures or selected + options to use less energy than mediumMinus(8). + + mediumMinus(8): Indicates that all Energy Object features are + available but the Energy Object has taken measures or selected + options to use less energy than medium(9). + + medium(9): Indicates that all Energy Object features are available + but the Energy Object has taken measures or selected options to + use less energy than highMinus(10). + + highMinus(10): Indicates that all Energy Object features are + available and the Energy Object has taken measures or selected + options to use less energy than high(11). + + high(11): Indicates that all Energy Object features are available + and the Energy Object may use the maximum energy as indicated + by the Nameplate Power. + +6.5.5. Power State Sets Comparison + + A comparison of Power States from different Power State Sets can be + seen in the following tables: + + Non-operational states: + + IEEE1621 DMTF ACPI EMAN + -------------------------------------------------- + off Off-Hard G3/S5 mechoff(0) + off Off-Soft G2/S5 softoff(1) + off Hibernate G1/S4 hibernate(2) + sleep Sleep-Deep G1/S3 sleep(3) + sleep Sleep-Light G1/S2 standby(4) + sleep Sleep-Light G1/S1 ready(5) + + + + + + + + + + + + +Parello, et al. Informational [Page 24] + +RFC 7326 EMAN Framework September 2014 + + + Operational states: + + IEEE1621 DMTF ACPI EMAN + ---------------------------------------------------- + on on G0/S0/P5 lowMinus(6) + on on G0/S0/P4 low(7) + on on G0/S0/P3 mediumMinus(8) + on on G0/S0/P2 medium(9) + on on G0/S0/P1 highMinus(10) + on on G0/S0/P0 high(11) + +6.6. Relationships + + The Energy Object (Class) contains a set of Relationship (Class) + attributes to model the relationships between devices and components. + Two Energy Objects can establish an Energy Object Relationship to + model the deployment topology with respect to Energy Management. + + Relationships are modeled with a Relationship (Class) that contains + the UUID of the other participant in the relationship and a name that + describes the type of relationship [CHEN]. The types of + relationships are Power Source, Metering, and Aggregations. + + o A Power Source Relationship is a relationship where one Energy + Object provides power to one or more Energy Objects. The Power + Source Relationship gives a view of the physical wiring topology + -- for example, a data center server receiving power from two + specific Power Interfaces from two different PDUs. + + Note: A Power Source Relationship may or may not change as the + direction of power changes between two Energy Objects. The + relationship may remain to indicate that the change of power + direction was unintended or an error condition. + + o A Metering Relationship is a relationship where one Energy Object + measures power, energy, demand, or Power Attributes of one or more + other Energy Objects. The Metering Relationship gives the view of + the Metering topology. Physical meters can be placed anywhere in + a power distribution tree. For example, utility meters monitor + and report accumulated power consumption of the entire building. + Logically, the Metering topology overlaps with the wiring + topology, as meters are connected to the wiring topology. A + typical example is meters that clamp onto the existing wiring. + + + + + + + + +Parello, et al. Informational [Page 25] + +RFC 7326 EMAN Framework September 2014 + + + o An Aggregation Relationship is a relationship where one Energy + Object aggregates Energy Management information of one or more + other Energy Objects. The Aggregation Relationship gives a model + of devices that may aggregate (sum, average, etc.) values for + other devices. The Aggregation Relationship is slightly different + compared to the other relationships, as this refers more to a + management function. + + In some situations, it is not possible to discover the Energy Object + Relationships, and an EnMS or administrator must set them. Given + that relationships can be assigned manually, the following sections + describe guidelines for use. + +6.6.1. Relationship Conventions and Guidelines + + This Energy Management framework does not impose many "MUST" rules + related to Energy Object Relationships. There are always corner + cases that can be excluded by making stricter specifications for + relationships. However, the framework proposes a series of + guidelines, indicated with "SHOULD" and "MAY". + +6.6.2. Guidelines: Power Source + + Power Source Relationships are intended to identify the connections + between Power Interfaces. This is analogous to a Layer 2 connection + in networking devices (a "one-hop connection"). + + The preferred modeling would be for Power Interfaces to participate + in Power Source Relationships. In some cases, Energy Objects may not + have the capability to model Power Interfaces. Therefore, a Power + Source Relationship can be established between two Energy Objects or + two non-connected Power Interfaces. + + Strictly speaking, while components and Power Interfaces on the same + Device do provide or receive energy from each other, the Power Source + Relationship is intended to show energy transfer between Devices. + Therefore, the relationship is implied when on the same Device. + + An Energy Object SHOULD NOT establish a Power Source Relationship + with a component. + + o A Power Source Relationship SHOULD be established with the next + known Power Interface in the wiring topology. + + + + + + + + +Parello, et al. Informational [Page 26] + +RFC 7326 EMAN Framework September 2014 + + + o The next known Power Interface in the wiring topology would be the + next device implementing the framework. In some cases, the domain + of devices under management may include some devices that do not + implement the framework. In these cases, the Power Source + Relationship can be established with the next device in the + topology that implements the framework and logically shows the + Power Source of the device. + + o Transitive Power Source Relationships SHOULD NOT be established. + For example, if Energy Object A has a Power Source Relationship + "Poweredby" with Energy Object B, and if Energy Object B has a + Power Source Relationship "Poweredby" with Energy Object C, then + Energy Object A SHOULD NOT have a Power Source Relationship + "Poweredby" with Energy Object C. + +6.6.3. Guidelines: Metering Relationship + + Metering Relationships are intended to show when one device acting as + a meter is measuring the power or energy at a point in a power + distribution system. Since one point of a power distribution system + may cover many devices within a wiring topology, this relationship + type can be seen as a set. + + Some devices may include hardware that can measure power for + components, outlets, or the entire device. For example, some PDUs + may have the ability to measure power for each outlet and are + commonly referred to as metered-by-outlet. Others may be able to + control power at each power outlet but can only measure power at the + power inlet -- commonly referred to as metered-by-device. + + While the Metering Relationship could be used to represent a device + as metered-by-outlet or metered-by-device, the Metering Relationship + SHOULD be used to model the relationship between a meter and all + devices covered by the meter downstream in the power distribution + system. + + In general: + + o A Metering Relationship MAY be established with any other Energy + Object, component, or Power Interface. + + o Transitive Metering Relationships MAY be used. + + o When there is a series of meters for one Energy Object, the Energy + Object MAY establish a Metering Relationship with one or more of + the meters. + + + + + +Parello, et al. Informational [Page 27] + +RFC 7326 EMAN Framework September 2014 + + +6.6.4. Guidelines: Aggregation + + Aggregation Relationships are intended to identify when one device is + used to accumulate values from other devices. Typically, this is for + energy or power values among devices and not for components or Power + Interfaces on the same device. + + The intent of Aggregation Relationships is to indicate when one + device is providing aggregate values for a set of other devices when + it is not obvious from the power source or simple containment within + a device. + + Establishing Aggregation Relationships within the same device would + make modeling more complex, and the aggregated values can be implied + from the use of power inlets, outlet, and Energy Object values on the + same device. + + Since an EnMS is naturally a point of Aggregation, it is not + necessary to model Aggregation for Energy Management Systems. + + The Aggregation Relationship is intended for power and energy. It + MAY be used for Aggregation of other values from the information + model, but the rules and logical ability to aggregate each attribute + are out of scope for this document. + + In general: + + o A Device SHOULD NOT establish an Aggregation Relationship with + components contained on the same device. + + o A Device SHOULD NOT establish an Aggregation Relationship with the + Power Interfaces contained on the same device. + + o A Device SHOULD NOT establish an Aggregation Relationship with an + EnMS. + + o Aggregators SHOULD log or provide notification in the case of + errors or missing values while performing Aggregation. + + + + + + + + + + + + + +Parello, et al. Informational [Page 28] + +RFC 7326 EMAN Framework September 2014 + + +6.6.5. Energy Object Relationship Extensions + + This framework for Energy Management is based on three relationship + types: Aggregation, Metering, and Power Source. + + This framework is defined with possible future extension of new + Energy Object Relationships in mind. + + For example: + + o Some Devices that may not be IP connected could be modeled with a + proxy relationship to an Energy Object within the domain. This + type of proxy relationship is left for further development. + + o A Power Distribution Unit (PDU) that allows devices and components + like outlets to be "ganged" together as a logical entity for + simplified management purposes could be modeled with an extension + called a "gang relationship", whose semantics would specify the + Energy Objects' grouping. + +7. Energy Management Information Model + + This section presents an information model expression of the concepts + in this framework as a reference for implementers. The information + model is implemented as MIB modules in the different related IETF + EMAN documents. However, other programming structures with different + data models could be used as well. + + Data modeling specifications of this information model may, where + needed, specify which attributes are required or optional. + + Syntax + + Unified Modeling + Language (UML) + Construct + [ISO-IEC-19501-2005] Equivalent Notation + -------------------- ---------------------------------- + Notes // Notes + + Class + (Generalization) CLASS name {member..} + Subclass + (Specialization) CLASS subclass + EXTENDS superclass {member..} + Class Member + (Attribute) attribute : type + + + + +Parello, et al. Informational [Page 29] + +RFC 7326 EMAN Framework September 2014 + + + Model + + CLASS EnergyObject { + + // identification / classification + index : int + name : string + identifier : uuid + alternatekey : string + + // context + domainName : string + role : string + keywords [0..n] : string + importance : int + + // relationship + relationships [0..n] : Relationship + + // measurements + nameplate : Nameplate + power : PowerMeasurement + energy : EnergyMeasurement + demand : DemandMeasurement + + // control + powerControl [0..n] : PowerStateSet + } + + CLASS PowerInterface EXTENDS EnergyObject { + eoIfType : enum { inlet, outlet, both } + } + + CLASS Device EXTENDS EnergyObject { + eocategory : enum { producer, consumer, meter, + distributor, store } + powerInterfaces [0..n] : PowerInterface + components [0..n] : Component + } + + CLASS Component EXTENDS EnergyObject { + eocategory : enum { producer, consumer, meter, + distributor, store } + powerInterfaces [0..n] : PowerInterface + components [0..n] : Component + } + + + + + +Parello, et al. Informational [Page 30] + +RFC 7326 EMAN Framework September 2014 + + + CLASS Nameplate { + nominalPower : PowerMeasurement + details : URI + } + + CLASS Relationship { + relationshipType : enum { meters, meteredby, powers, + poweredby, aggregates, aggregatedby } + relationshipObject : uuid + } + + CLASS Measurement { + multiplier : enum { -24..24 } + caliber : enum { actual, estimated, static } + accuracy : enum { 0..10000 } // hundreds of percent + } + + CLASS PowerMeasurement EXTENDS Measurement { + value : long + units : "W" + powerAttribute : PowerAttribute + } + + CLASS EnergyMeasurement EXTENDS Measurement { + startTime : time + units : "kWh" + provided : long + used : long + produced : long + stored : long + + } + + CLASS TimedMeasurement EXTENDS Measurement { + startTime : timestamp + value : Measurement + maximum : Measurement + } + + CLASS TimeInterval { + value : long + units : enum { seconds, milliseconds,... } + } + + + + + + + + +Parello, et al. Informational [Page 31] + +RFC 7326 EMAN Framework September 2014 + + + CLASS DemandMeasurement EXTENDS Measurement { + intervalLength : TimeInterval + intervals : long + intervalMode : enum { periodic, sliding, total } + intervalWindow : TimeInterval + sampleRate : TimeInterval + status : enum { active, inactive } + measurements [0..n] : TimedMeasurements + } + + CLASS PowerStateSet { + powerSetIdentifier : int + name : string + powerStates [0..n] : PowerState + operState : int + adminState : int + reason : string + configuredTime : timestamp + } + + CLASS PowerState { + powerStateIdentifier : int + name : string + cardinality : int + maximumPower : PowerMeasurement + totalTimeInState : time + entryCount : long + } + + CLASS PowerAttribute { + acQuality : ACQuality + } + + CLASS ACQuality { + acConfiguration : enum { SNGL, DEL, WYE } + avgVoltage : long + avgCurrent : long + thdCurrent : long + frequency : long + unitMultiplier : int + accuracy : int + totalActivePower : long + totalReactivePower : long + totalApparentPower : long + totalPowerFactor : long + } + + + + + +Parello, et al. Informational [Page 32] + +RFC 7326 EMAN Framework September 2014 + + + CLASS DelPhase EXTENDS ACQuality { + phaseToNextPhaseVoltage : long + thdVoltage : long + } + + CLASS WYEPhase EXTENDS ACQuality { + phaseToNeutralVoltage : long + thdCurrent : long + thdVoltage : long + avgCurrent : long + } + +8. Modeling Relationships between Devices + + In this section, we give examples of how to use the EMAN information + model to model physical topologies. Where applicable, we show how + the framework can be applied when devices can be modeled with Power + Interfaces. We also show how the framework can be applied when + devices cannot be modeled with Power Interfaces but only monitored or + controlled as a whole. For instance, a PDU may only be able to + measure power and energy for the entire unit without the ability to + distinguish among the inlets or outlets. + +8.1. Power Source Relationship + + The Power Source Relationship is used to model the interconnections + between devices, components, and/or Power Interfaces to indicate the + source of energy for a device. + + In the following examples, we show variations on modeling the + reference topologies using relationships. + + Given for all cases: + + Device W: A computer with one power supply. Power Interface 1 is an + inlet for Device W. + + Device X: A computer with two power supplies. Power Interface 1 and + Power Interface 2 are both inlets for Device X. + + Device Y: A PDU with multiple Power Interfaces numbered 0..10. Power + Interface 0 is an inlet, and Power Interfaces 1..10 are outlets. + + Device Z: A PDU with multiple Power Interfaces numbered 0..10. Power + Interface 0 is an inlet, and Power Interfaces 1..10 are outlets. + + + + + + +Parello, et al. Informational [Page 33] + +RFC 7326 EMAN Framework September 2014 + + + Case 1: Simple Device with one Source + + Physical Topology: + + o Device W inlet 1 is plugged into Device Y outlet 8. + + With Power Interfaces: + + o Device W has an Energy Object representing the computer + itself as well as one Power Interface defined as an inlet. + + o Device Y would have an Energy Object representing the PDU + itself (the Device), with Power Interface 0 defined as an + inlet and Power Interfaces 1..10 defined as outlets. + + The interfaces of the devices would have a Power Source + Relationship such that: + + Device W inlet 1 is powered by Device Y outlet 8. + + +-------+------+ poweredBy +------+----------+ + | PDU Y | PI 8 |-----------------| PI 1 | Device W | + +-------+------+ powers +------+----------+ + + Without Power Interfaces: + + o Device W has an Energy Object representing the computer. + + o Device Y would have an Energy Object representing the PDU. + + The devices would have a Power Source Relationship such that: + + Device W is powered by Device Y. + + +----------+ poweredBy +------------+ + | PDU Y |-----------------| Device W | + +----------+ powers +------------+ + + + + + + + + + + + + + + +Parello, et al. Informational [Page 34] + +RFC 7326 EMAN Framework September 2014 + + + Case 2: Multiple Inlets + + Physical Topology: + + o Device X inlet 1 is plugged into Device Y outlet 8. + + o Device X inlet 2 is plugged into Device Y outlet 9. + + With Power Interfaces: + + o Device X has an Energy Object representing the computer + itself. It contains two Power Interfaces defined as inlets. + + o Device Y would have an Energy Object representing the PDU + itself (the Device), with Power Interface 0 defined as an + inlet and Power Interfaces 1..10 defined as outlets. + + The interfaces of the devices would have a Power Source + Relationship such that: + + Device X inlet 1 is powered by Device Y outlet 8. + + Device X inlet 2 is powered by Device Y outlet 9. + + +-------+------+ poweredBy+------+----------+ + | | PI 8 |-----------------| PI 1 | | + | | |powers | | | + | PDU Y +------+ poweredBy+------+ Device X | + | | PI 9 |-----------------| PI 2 | | + | | |powers | | | + +-------+------+ +------+----------+ + + Without Power Interfaces: + + o Device X has an Energy Object representing the computer. + Device Y has an Energy Object representing the PDU. + + The devices would have a Power Source Relationship such that: + + Device X is powered by Device Y. + + +----------+ poweredBy +------------+ + | PDU Y |-----------------| Device X | + +----------+ powers +------------+ + + + + + + + +Parello, et al. Informational [Page 35] + +RFC 7326 EMAN Framework September 2014 + + + Case 3: Multiple Sources + + Physical Topology: + + o Device X inlet 1 is plugged into Device Y outlet 8. + + o Device X inlet 2 is plugged into Device Z outlet 9. + + With Power Interfaces: + + o Device X has an Energy Object representing the computer + itself. It contains two Power Interfaces defined as inlets. + + o Device Y would have an Energy Object representing the PDU + itself (the Device), with Power Interface 0 defined as an + inlet and Power Interfaces 1..10 defined as outlets. + + o Device Z would have an Energy Object representing the PDU + itself (the Device), with Power Interface 0 defined as an + inlet and Power Interfaces 1..10 defined as outlets. + + The interfaces of the devices would have a Power Source + Relationship such that: + + Device X inlet 1 is powered by Device Y outlet 8. + + Device X inlet 2 is powered by Device Z outlet 9. + + +-------+------+ poweredBy+------+----------+ + | PDU Y | PI 8 |-----------------| PI 1 | | + | | |powers | | | + +-------+------+ +------+ | + | Device X | + +-------+------+ poweredBy+------+ | + | PDU Z | PI 9 |-----------------| PI 2 | | + | | |powers | | | + +-------+------+ +------+----------+ + + Without Power Interfaces: + + o Device X has an Energy Object representing the computer. + Devices Y and Z would both have respective Energy Objects + representing each entire PDU. + + + + + + + + +Parello, et al. Informational [Page 36] + +RFC 7326 EMAN Framework September 2014 + + + The devices would have a Power Source Relationship such that: + + Device X is powered by Device Y and powered by Device Z. + + +----------+ poweredBy +------------+ + | PDU Y |---------------------| Device X | + +----------+ powers +------------+ + + +----------+ poweredBy +------------+ + | PDU Z |---------------------| Device X | + +----------+ powers +------------+ + +8.2. Metering Relationship + + A meter in a power distribution system can logically measure the + power or energy for all devices downstream from the meter in the + power distribution system. As such, a Metering Relationship can be + seen as a relationship between a meter and all of the devices + downstream from the meter. + + We define in this case a Metering Relationship between a meter and + devices downstream from the meter. + + +-----+---+ meteredBy +--------+ poweredBy +-------+ + |Meter| PI|--------------| switch |-------------| phone | + +-----+---+ meters +--------+ powers +-------+ + | | + | meteredBy | + +-------------------------------------------+ + meters + + In cases where the Power Source topology cannot be discovered or + derived from the information available in the Energy Management + Domain, the Metering topology can be used to relate the upstream + meter to the downstream devices in the absence of specific Power + Source Relationships. + + + + + + + + + + + + + + + +Parello, et al. Informational [Page 37] + +RFC 7326 EMAN Framework September 2014 + + + A Metering Relationship can occur between devices that are not + directly connected, as shown in the following figure: + + +---------------+ + | Device 1 | + +---------------+ + | PI | + +---------------+ + | + +---------------+ + | Meter | + +---------------+ + . + . + . + meters meters meters + +----------+ +----------+ +-----------+ + | Device A | | Device B | | Device C | + +----------+ +----------+ +-----------+ + + An analogy to communications networks would be modeling connections + between servers (meters) and clients (devices) when the complete + Layer 2 topology between the servers and clients is not known. + +8.3. Aggregation Relationship + + Some devices can act as Aggregation points for other devices. For + example, a PDU controller device may contain the summation of power + and energy readings for many PDU devices. The PDU controller will + have aggregate values for power and energy for a group of PDU + devices. + + This Aggregation is independent of the physical power or + communication topology. + + The functions that the Aggregation point may perform include the + calculation of values such as average, count, maximum, median, + minimum, or the listing (collection) of the Aggregation values, etc. + + Based on IETF experience gained on Aggregations [RFC7015], the + Aggregation function in the EMAN framework is limited to the + summation. + + When Aggregation occurs across a set of entities, values to be + aggregated may be missing for some entities. The EMAN framework does + not specify how these should be treated, as different implementations + may have good reason to take different approaches. One common + treatment is to define the Aggregation as missing if any of the + + + +Parello, et al. Informational [Page 38] + +RFC 7326 EMAN Framework September 2014 + + + constituent elements are missing (useful to be most precise). + Another is to treat the missing value as zero (useful to have + continuous data streams). + + The specifications of Aggregation functions are out of the scope of + the EMAN framework but must be clearly specified by the equipment + vendor. + +9. Relationship to Other Standards + + This Energy Management framework uses, as much as possible, existing + standards, especially with respect to information modeling and data + modeling [RFC3444]. + + The data model for power- and energy-related objects is based on + [IEC61850]. + + Specific examples include: + + o The scaling factor, which represents Energy Object usage + magnitude, conforms to the [IEC61850] definition of unit + multiplier for the SI (System International) units of measure. + + o The electrical characteristics are based on the ANSI and IEC + Standards, which require that we use an accuracy class for power + measurement. ANSI and IEC define the following accuracy classes + for power measurement: + + - IEC 62053-22 and 60044-1 classes 0.1, 0.2, 0.5, 1, and 3. + + - ANSI C12.20 classes 0.2 and 0.5. + + o The electrical characteristics and quality adhere closely to the + [IEC61850-7-4] standard for describing AC measurements. + + o The Power State definitions are based on the DMTF Power State + Profile and ACPI models, with operational state extensions. + +10. Security Considerations + + Regarding the data attributes specified here, some or all may be + considered sensitive or vulnerable in some network environments. + Reading or writing these attributes without proper protection such as + encryption or access authorization will have negative effects on + network capabilities. Event logs for audit purposes on configuration + and other changes should be generated according to current + + + + + +Parello, et al. Informational [Page 39] + +RFC 7326 EMAN Framework September 2014 + + + authorization, audit, and accounting principles to facilitate + investigations (compromise or benign misconfigurations) or any + reporting requirements. + + The information and control capabilities specified in this framework + could be exploited, to the detriment of a site or deployment. + Implementers of the framework SHOULD examine and mitigate security + threats with respect to these new capabilities. + + "User-based Security Model (USM) for version 3 of the Simple Network + Management Protocol (SNMPv3)" [RFC3414] presents a good description + of threats and mitigations for SNMPv3 that can be used as a guide for + implementations of this framework using other protocols. + +10.1. Security Considerations for SNMP + + Readable objects in MIB modules (i.e., objects with a MAX-ACCESS + other than not-accessible) may be considered sensitive or vulnerable + in some network environments. It is important to control GET and/or + NOTIFY access to these objects and possibly to encrypt the values of + these objects when sending them over the network via SNMP. + + The support for SET operations in a non-secure environment without + proper protection can have a negative effect on network operations. + + For example: + + o Unauthorized changes to the Energy Management Domain or business + context of a device will result in misreporting or interruption of + power. + + o Unauthorized changes to a Power State will disrupt the power + settings of the different devices and therefore the state of + functionality of the respective devices. + + o Unauthorized changes to the demand history will disrupt proper + accounting of energy usage. + + With respect to data transport, SNMP versions prior to SNMPv3 did not + include adequate security. Even if the network itself is secure (for + example, by using IPsec), there is still no secure control over who + on the secure network is allowed to access and GET/SET + (read/change/create/delete) the objects in these MIB modules. + + It is recommended that implementers consider the security features as + provided by the SNMPv3 framework (see [RFC3411]), including full + support for the SNMPv3 cryptographic mechanisms (for authentication + and confidentiality). + + + +Parello, et al. Informational [Page 40] + +RFC 7326 EMAN Framework September 2014 + + + Further, deployment of SNMP versions prior to SNMPv3 is not + recommended. Instead, it is recommended to deploy SNMPv3 and to + enable cryptographic security. It is then a customer/operator + responsibility to ensure that the SNMP entity giving access to an + instance of these MIB modules is properly configured to give access + to the objects only to those principals (users) that have legitimate + rights to GET or SET (change/create/delete) them. + +11. IANA Considerations + +11.1. IANA Registration of New Power State Sets + + This document specifies an initial set of Power State Sets. The list + of these Power State Sets with their numeric identifiers is given in + Section 6. IANA maintains the lists of Power State Sets. + + New assignments for a Power State Set are administered by IANA + through Expert Review [RFC5226], i.e., review by one of a group of + experts designated by an IETF Area Director. The group of experts + must check the requested state for completeness and accuracy of the + description. A pure vendor-specific implementation of a Power State + Set shall not be adopted, since it would lead to proliferation of + Power State Sets. + + Power States in a Power State Set are limited to 255 distinct values. + A new Power State Set must be assigned the next available numeric + identifier that is a multiple of 256. + +11.1.1. IANA Registration of the IEEE1621 Power State Set + + This document specifies a set of values for the IEEE1621 Power State + Set [IEEE1621]. The list of these values with their identifiers is + given in Section 6.5.2. IANA created a new registry for IEEE1621 + Power State Set identifiers and filled it with the initial list of + identifiers. + + New assignments (or, potentially, deprecation) for the IEEE1621 Power + State Set are administered by IANA through Expert Review [RFC5226]. + +11.1.2. IANA Registration of the DMTF Power State Set + + This document specifies a set of values for the DMTF Power State Set + [DMTF]. The list of these values with their identifiers is given in + Section 6.5.3. IANA has created a new registry for DMTF Power State + Set identifiers and filled it with the initial list of identifiers. + + New assignments (or, potentially, deprecation) for the DMTF Power + State Set are administered by IANA through Expert Review [RFC5226]. + + + +Parello, et al. Informational [Page 41] + +RFC 7326 EMAN Framework September 2014 + + + The group of experts must check for conformance with the DMTF + standard [DMTF] in addition to checking for completeness and accuracy + of the description. + +11.1.3. IANA Registration of the EMAN Power State Set + + This document specifies a set of values for the EMAN Power State Set. + The list of these values with their identifiers is given in + Section 6.5.4. IANA has created a new registry for EMAN Power State + Set identifiers and filled it with the initial list of identifiers. + + New assignments (or, potentially, deprecation) for the EMAN Power + State Set are administered by IANA through Expert Review [RFC5226]. + +11.2. Updating the Registration of Existing Power State Sets + + With the evolution of standards, over time, it may be important to + deprecate some of the existing Power State Sets, or to add or + deprecate some Power States within a Power State Set. + + The registrant shall post an Internet-Draft with the clear + specification on deprecation of Power State Sets or Power States + registered with IANA. The deprecation or addition shall be + administered by IANA through Expert Review [RFC5226], i.e., review by + one of a group of experts designated by an IETF Area Director. The + process should also allow for a mechanism for cases where others have + significant objections to claims regarding the deprecation of a + registration. + + + + + + + + + + + + + + + + + + + + + + + +Parello, et al. Informational [Page 42] + +RFC 7326 EMAN Framework September 2014 + + +12. References + +12.1. Normative References + + [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate + Requirement Levels", BCP 14, RFC 2119, March 1997. + + [RFC3411] Harrington, D., Presuhn, R., and B. Wijnen, "An + Architecture for Describing Simple Network Management + Protocol (SNMP) Management Frameworks", STD 62, RFC 3411, + December 2002. + + [RFC3414] Blumenthal, U. and B. Wijnen, "User-based Security Model + (USM) for version 3 of the Simple Network Management + Protocol (SNMPv3)", STD 62, RFC 3414, December 2002. + + [RFC3444] Pras, A. and J. Schoenwaelder, "On the Difference between + Information Models and Data Models", RFC 3444, + January 2003. + + [RFC4122] Leach, P., Mealling, M., and R. Salz, "A Universally + Unique IDentifier (UUID) URN Namespace", RFC 4122, + July 2005. + + [RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an + IANA Considerations Section in RFCs", BCP 26, RFC 5226, + May 2008. + + [RFC6933] Bierman, A., Romascanu, D., Quittek, J., and M. + Chandramouli, "Entity MIB (Version 4)", RFC 6933, + May 2013. + + [RFC6988] Quittek, J., Ed., Chandramouli, M., Winter, R., Dietz, T., + and B. Claise, "Requirements for Energy Management", + RFC 6988, September 2013. + + [ISO-IEC-19501-2005] + ISO/IEC 19501:2005, Information technology, Open + Distributed Processing -- Unified Modeling Language (UML) + Version 1.4.2, January 2005. + + + + + + + + + + + +Parello, et al. Informational [Page 43] + +RFC 7326 EMAN Framework September 2014 + + +12.2. Informative References + + [RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform + Resource Identifier (URI): Generic Syntax", STD 66, + RFC 3986, January 2005. + + [RFC7015] Trammell, B., Wagner, A., and B. Claise, "Flow Aggregation + for the IP Flow Information Export (IPFIX) Protocol", + RFC 7015, September 2013. + + [ACPI] "Advanced Configuration and Power Interface + Specification", October 2006, + <http://www.acpi.info/spec30b.htm>. + + [IEEE1621] "Standard for User Interface Elements in Power Control of + Electronic Devices Employed in Office/Consumer + Environments", IEEE 1621, December 2004. + + [NMF] Clemm, A., "Network Management Fundamentals", + ISBN-10: 1-58720-137-2, Cisco Press, November 2006. + + [TMN] International Telecommunication Union, "TMN management + functions", ITU-T Recommendation M.3400, February 2000. + + [IEEE100] "The Authoritative Dictionary of IEEE Standards Terms", + <http://ieeexplore.ieee.org/xpl/ + mostRecentIssue.jsp?punumber=4116785>. + + [ISO50001] "ISO 50001:2011 Energy management systems -- Requirements + with guidance for use", June 2011, <http://www.iso.org/>. + + [IEC60050] "International Electrotechnical Vocabulary", + <http://www.electropedia.org/iev/iev.nsf/ + welcome?openform>. + + [IEC61850] "Power Utility Automation", + <http://www.iec.ch/smartgrid/standards/>. + + [IEC61850-7-2] + "Abstract communication service interface (ACSI)", + <http://www.iec.ch/smartgrid/standards/>. + + [IEC61850-7-4] + "Compatible logical node classes and data classes", + <http://www.iec.ch/smartgrid/standards/>. + + + + + + +Parello, et al. Informational [Page 44] + +RFC 7326 EMAN Framework September 2014 + + + [DMTF] "Power State Management Profile", DMTF DSP1027 + Version 2.0.0, December 2009, + <http://www.dmtf.org/sites/default/files/standards/ + documents/DSP1027_2.0.0.pdf>. + + [IPENERGY] Aldrich, R. and J. Parello, "IP-Enabled Energy Management: + A Proven Strategy for Administering Energy as a Service", + 2010, Wiley Publishing. + + [X.700] CCITT Recommendation X.700, "Management framework for Open + Systems Interconnection (OSI) for CCITT applications", + September 1992. + + [ASHRAE-201] + "ASHRAE Standard Project Committee 201 (SPC 201) Facility + Smart Grid Information Model", + <http://spc201.ashraepcs.org>. + + [CHEN] Chen, P., "The Entity-Relationship Model: Toward a Unified + View of Data", ACM Transactions on Database Systems + (TODS), March 1976. + + [CISCO-EW] Parello, J., Saville, R., and S. Kramling, "Cisco + EnergyWise Design Guide", Cisco Validated Design (CVD), + September 2011, + <http://www.cisco.com/en/US/docs/solutions/ + Enterprise/Borderless_Networks/Energy_Management/ + energywisedg.html>. + +13. Acknowledgments + + The authors would like to thank Michael Brown for his editorial work, + which improved the text dramatically. Thanks to Rolf Winter for his + feedback, and to Bill Mielke for his feedback and very detailed + review. Thanks to Bruce Nordman for brainstorming, with numerous + conference calls and discussions. Finally, the authors would like to + thank the EMAN chairs: Nevil Brownlee, Bruce Nordman, and Tom Nadeau. + + + + + + + + + + + + + + +Parello, et al. Informational [Page 45] + +RFC 7326 EMAN Framework September 2014 + + +Appendix A. Information Model Listing + + A. EnergyObject (Class): + + r index Integer An [RFC6933] entPhysicalIndex + + w name String An [RFC6933] entPhysicalName + + r identifier uuid An [RFC6933] entPhysicalUUID + + rw alternatekey String A manufacturer-defined string + that can be used to identify the + Energy Object + + rw domainName String The name of an Energy Management + Domain for the Energy Object + + rw role String An administratively assigned name + to indicate the purpose an + Energy Object serves in the + network + + rw keywords String A list of keywords or [0..n] tags + that can be used to group Energy + Objects for reporting or + searching + + rw importance Integer Specifies a ranking of how + important the Energy Object is + (on a scale of 1 to 100) compared + with other Energy Objects + + rw relationships Relationship A list of relationships between + [0..n] this Energy Object and other + Energy Objects + + r nameplate Nameplate The nominal PowerMeasurement of + the Energy Object as specified by + the device manufacturer + + r power PowerMeasurement The present power measurement of + the Energy Object + + r energy EnergyMeasurement The present energy measurement + for the Energy Object + + r demand DemandMeasurement The present demand measurement + for the Energy Object + + + +Parello, et al. Informational [Page 46] + +RFC 7326 EMAN Framework September 2014 + + + r powerControl PowerStateSet A list of Power States Sets the + [0..n] Energy Object supports + + + B. PowerInterface (Class) inherits from EnergyObject: + + r eoIfType Enumeration Indicates whether the Power + Interface is an inlet, outlet, + or both + + + C. Device (Class) inherits from EnergyObject: + + rw eocategory Enumeration Broadly indicates whether + the Device is a producer, + consumer, meter, distributor, + or store of energy + + r powerInterfaces PowerInterface A list of PowerInterfaces + [0..n] contained in this Device + + r components Component A list of components + [0..n] contained in this Device + + + D. Component (Class) inherits from EnergyObject: + + rw eocategory Enumeration Broadly indicates whether the + component is a producer, + consumer, meter, distributor, or + store of energy + + r powerInterfaces PowerInterface A list of PowerInterfaces + [0..n] contained in this component + + r components Component A list of components contained + [0..n] in this component + + + + + + + + + + + + + + +Parello, et al. Informational [Page 47] + +RFC 7326 EMAN Framework September 2014 + + + E. Nameplate (Class): + + r nominalPower PowerMeasurement The nominal power of the Energy + as specified by the device + manufacturer + + rw details URI An [RFC3986] URI that links to + manufacturer information about + the nominal power of a device + + + F. Relationship (Class): + + rw relationshipType Enumeration A description of the + relationship, indicating + meters, meteredby, powers, + poweredby, aggregates, or + aggregatedby + + rw relationshipObject uuid An [RFC6933] entPhysicalUUID + that indicates the other + participating Energy Object in + the relationship + + + G. Measurement (Class): + + r multiplier Enumeration The magnitude of the Measurement + in the range -24..24 + + r caliber Enumeration Specifies how the Measurement was + obtained -- actual, estimated, or + static + + r accuracy Enumeration Specifies the accuracy of the + measurement, if applicable, as + 0..10000, indicating hundreds of + percent + + + H. PowerMeasurement (Class) inherits from Measurement: + + r value Long A measurement value of + power + + r units "W" The units of measure for + the power -- "Watts" + + + + +Parello, et al. Informational [Page 48] + +RFC 7326 EMAN Framework September 2014 + + + r powerAttribute PowerAttribute Measurement of the electrical + current -- voltage, phase, and/or + frequencies for the + PowerMeasurement + + + I. EnergyMeasurement (Class) inherits from Measurement: + + r startTime Time Specifies the start time of the + EnergyMeasurement interval + + r units "kWh" The units of measure for the energy -- + kilowatt-hours + + r provided Long A measurement of energy provided + + r used Long A measurement of energy used/consumed + + r produced Long A measurement of energy produced + + r stored Long A measurement of energy stored + + + J. TimedMeasurement (Class) inherits from Measurement: + + r startTime timestamp A start time of a measurement + + r value Measurement A measurement value + + r maximum Measurement A maximum value measured since a previous + timestamp + + + K. TimeInterval (Class): + + r value Long A value of time + + r units Enumeration A magnitude of time, expressed as seconds + with an SI prefix (milliseconds, etc.) + + + L. DemandMeasurement (Class) inherits from Measurement: + + rw intervalLength TimeInterval The length of time over which to + compute average energy + + rw intervals Long The number of intervals that can + be measured + + + +Parello, et al. Informational [Page 49] + +RFC 7326 EMAN Framework September 2014 + + + rw intervalMode Enumeration The mode of interval + measurement -- periodic, sliding, + or total + + rw intervalWindow TimeInterval The duration between the starting + time of one sliding window and + the next starting time + + rw sampleRate TimeInterval The sampling rate at which to + poll power in order to compute + demand + + rw status Enumeration A control to start or stop demand + measurement -- active or inactive + + r measurements TimedMeasurement A collection of TimedMeasurements + [0..n] to compute demand + + + M. PowerStateSet (Class): + + r powerSetIdentifier Integer An IANA-assigned value indicating + a Power State Set + + r name String A Power State Set name + + r powerStates PowerState A set of Power States for the + [0..n] given identifier + + rw operState Integer The current operational Power + State + + rw adminState Integer The desired Power State + + rw reason String Describes the reason + for the adminState + + r configuredTime timestamp Indicates the time of + the desired Power State + + + N. PowerState (Class): + + r powerStateIdentifier Integer An IANA-assigned value + indicating a Power State + + r name String A name for the Power State + + + + +Parello, et al. Informational [Page 50] + +RFC 7326 EMAN Framework September 2014 + + + r cardinality Integer A value indicating an + ordering of the Power State + + rw maximumPower PowerMeasurement Indicates the maximum power + for the Energy Object at + this Power State + + r totalTimeInState Time Indicates the total time + an Energy Object has been + in this Power State since + the last reset + + r entryCount Long Indicates the number of + times the Energy Object + has entered or changed to + this state + + + O. PowerAttribute (Class): + + r acQuality ACQuality Describes AC Power Attributes for + a Measurement + + P. ACQuality (Class): + + r acConfiguration Enumeration Describes the physical + configuration of alternating + current as single phase (SNGL), + three-phase delta (DEL), or + three-phase Y (WYE) + + r avgVoltage Long The average of the voltage measured + over an integral number of AC + cycles [IEC61850-7-4] 'Vol' + + r avgCurrent Long The current per phase + [IEC61850-7-4] 'Amp' + + r thdCurrent Long A calculated value for the current + Total Harmonic Distortion (THD). + The method of calculation is not + specified [IEC61850-7-4] 'ThdAmp' + + r frequency Long Basic frequency of the AC circuit + [IEC61850-7-4] 'Hz' + + r unitMultiplier Integer Magnitude of watts for the usage + value in this instance + + + +Parello, et al. Informational [Page 51] + +RFC 7326 EMAN Framework September 2014 + + + r accuracy Integer Percentage value in 100ths + of a percent, representing the + presumed accuracy of active, + reactive, and apparent power + in this instance + + r totalActivePower Long A measured value of the actual + power delivered to or consumed by + the load [IEC61850-7-4] 'TotW' + + r totalReactivePower Long A measured value of the reactive + portion of the apparent power + [IEC61850-7-4] 'TotVAr' + + r totalApparentPower Long A measured value of the voltage + and current, which determines the + apparent power as the vector sum of + real and reactive power + [IEC61850-7-4] 'TotVA' + + r totalPowerFactor Long A measured value of the ratio of + the real power flowing to the load + versus the apparent power + [IEC61850-7-4] 'TotPF' + + + Q. DelPhase (Class) inherits from ACQuality: + + r phaseToNext Long A measured value of phase to + PhaseVoltage next phase voltages where the + next phase is [IEC61850-7-4] + 'PPV' + + r thdVoltage Long A calculated value for the + voltage Total Harmonic Distortion + (THD) for phase to next phase. + The method of calculation is not + specified [IEC61850-7-4] 'ThdPPV' + + + + + + + + + + + + + +Parello, et al. Informational [Page 52] + +RFC 7326 EMAN Framework September 2014 + + + R. WYEPhase (Class) inherits from ACQuality: + + r phaseToNeutral Long A measured value of phase to + Voltage neutral voltage [IEC61850-7-4] + 'PhV' + + r thdCurrent Long A calculated value for the current + Total Harmonic Distortion (THD). + The method of calculation is not + specified [IEC61850-7-4] 'ThdA' + + r thdVoltage Long A calculated value of the voltage + THD for phase to neutral + [IEC61850-7-4] 'ThdPhV' + + r avgCurrent Long A measured value of phase currents + [IEC61850-7-4] 'A' + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +Parello, et al. Informational [Page 53] + +RFC 7326 EMAN Framework September 2014 + + +Authors' Addresses + + John Parello + Cisco Systems, Inc. + 3550 Cisco Way + San Jose, CA 95134 + US + + Phone: +1 408 525 2339 + EMail: jparello@cisco.com + + + Benoit Claise + Cisco Systems, Inc. + De Kleetlaan 6a b1 + Diegem 1813 + BE + + Phone: +32 2 704 5622 + EMail: bclaise@cisco.com + + + Brad Schoening + 44 Rivers Edge Drive + Little Silver, NJ 07739 + US + + EMail: brad.schoening@verizon.net + + + Juergen Quittek + NEC Europe Ltd. + Network Laboratories + Kurfuersten-Anlage 36 + 69115 Heidelberg + Germany + + Phone: +49 6221 90511 15 + EMail: quittek@netlab.nec.de + + + + + + + + + + + + +Parello, et al. Informational [Page 54] + |