Export of Energy Consumption Information in IPFIX

Introduction Energy consumption has emerged as a critical operational metric in modern data centers and communication networks, driven by increasing demands for sustainability and cost efficiency. Operators require accurate, traffic-correlated energy information to support applications such as energy-aware routing, per-service energy cost accounting, and fine-grained energy management. General-purpose device energy monitoring solutions represented by YANG Push telemetry are designed for full-lifecycle energy status collection of devices and components, with periodic or state-change-triggered reporting as the native working mode. For scenarios that require deep binding of energy metrics with traffic flow events, additional subscription policy configuration and cross-dataset time alignment processing are required on the management side. In contrast, the IP Flow Information Export (IPFIX) protocol is natively built around traffic flow metering and event-driven reporting. It can inherently associate energy observations with traffic events at the data source, providing causal and time-aligned traffic-energy associated data without additional post-processing. To address these needs, this document defines six new Information Elements (IEs) that enable an IPFIX Exporting Process to report energy consumption for physical entities within a network device, including the entire device, line cards, and ports. The semantic definition of these metrics is aligned with the GREEN WG Power and Energy YANG module to ensure data consistency across different telemetry protocols. These IEs support both instantaneous (realtime) power values, which provide snapshots at the moment of export for immediate analysis, and average power values over the measurement interval since the last export, which are useful for trend detection and aggregated accounting. The measurements are exported via existing IPFIX triggering mechanisms, such as packet count thresholds, active timeouts, and inactive timeouts—preserving causality between observed traffic and reported power metrics. This document introduces new IPFIX IEs for exporting energy consumption information of physical entities in a network device to facilitate energy-aware networking by providing granular, real-time data for optimized network operations.

Requirements Language 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 .

Terminology This document makes use of the terms defined in :

IPFIX
IPFIX Information Elements
Exporting Process
Metering Process
Template Record
Data Record
Exporter
Collector

For energy efficiency related concepts, this document follows the definitions specified in .

New IPFIX IEs for Energy Consumption Information The following new Information Elements are defined:

deviceRealtimePower Name：deviceRealtimePower ElementID: TBD1 Description: Instantaneous total power consumption of the entire exporting device at the time of export. To support interoperability across telemetry protocols, it is RECOMMENDED that the semantic of this IE aligns with the device-level instantaneous-power leaf defined in the GREEN Power and Energy YANG module. Abstract Data Type: unsigned32 Data Type Semantics: quantity Units: watts Reference: This document and .

deviceAveragePower Name：deviceAveragePower ElementID: TBD2 Description: Average total power consumption of the entire exporting device over the interval since the last export of this Template.It is RECOMMENDED that the unit and measurement caliber of this IE align with the power metrics defined in the GREEN Power and Energy YANG module, to ensure cross-protocol data comparability. Abstract Data Type: unsigned32 Data Type Semantics: quantity Units: watts Reference: This document and .

lineCardRealtimePower Name：lineCardRealtimePower ElementID: TBD3 Description: Instantaneous power consumption of the line card at the time of export.To support interoperability across telemetry protocols, it is RECOMMENDED that the semantic of this IE aligns with the component-level instantaneous-power leaf defined in the GREEN Power and Energy YANG module. Abstract Data Type: unsigned32 Data Type Semantics: quantity Units: milliwatts Reference: This document and .

lineCardAveragePower Name：lineCardAveragePower ElementID: TBD4 Description: Average power consumption of the line card identified over the interval since the last export. It is RECOMMENDED that the unit and measurement caliber of this IE align with the power metrics defined in the GREEN Power and Energy YANG module, to ensure cross-protocol data comparability. Abstract Data Type: unsigned32 Data Type Semantics: quantity Units: milliwatts Reference: This document and .

portRealtimePower Name：portRealtimePower ElementID: TBD5 Description: Instantaneous power consumption of the port at the time of export.To support interoperability across telemetry protocols, it is RECOMMENDED that the semantic of this IE aligns with the component-level instantaneous-power leaf defined in the GREEN Power and Energy YANG module. Abstract Data Type: unsigned32 Data Type Semantics: quantity Units: milliwatts Reference: This document and .

portAveragePower Name：portAveragePower ElementID: TBD6 Description: Average power consumption of the port over the interval since the last export.It is RECOMMENDED that the unit and measurement caliber of this IE align with the power metrics defined in the GREEN Power and Energy YANG module, to ensure cross-protocol data comparability. Abstract Data Type: unsigned32 Data Type Semantics: quantity Units: milliwatts Reference: This document and .

Use Cases

Energy-Aware Routing This use case aligns with the "Selective reduction of energy consumption in network parts proportional to traffic levels" and "Fixed Network Energy Saving" use cases defined in . In this scenario, network controllers may require accurate, traffic-correlated energy consumption metrics of physical links (represented by ports) to compute paths that minimize total energy cost. For energy-aware routing scenarios, the accuracy of routing decisions depends on the time synchronization between traffic load data and energy consumption data at the moment of path calculation. General periodic telemetry reports both metrics independently; time offsets may degrade energy cost calculation precision.This IPFIX-based solution encapsulates traffic statistics and power measurements in a single traffic-triggered data record, ensuring natural time alignment for more accurate routing computation. By leveraging the IPFIX-based energy telemetry defined in this document, a network device can export multi-level energy consumption data (e.g., port, line card, and device levels) triggered by traffic events such as packet count thresholds or active/inactive timeouts. The exported data records can provide both instantaneous and average power values over the observation interval, enabling the controller to derive meaningful energy cost metrics, such as per-link power-per-bit or average power under load, for use in path computation algorithms. This tight coupling between traffic behavior and energy reporting ensures that routing decisions reflect real-time energy efficiency characteristics of network links.

Per-Flow Energy Consumption Monitoring For fine-grained energy accounting and auditing of specific high-bandwidth ("elephant") flows, such as backup traffic between data center servers, it is essential to attribute the energy consumed across multiple physical components (e.g., ingress/egress ports and their respective line cards) to the flow itself. Using the mechanisms described in this document, an IPFIX Exporting Process can associate energy consumption measurements with a specific IP flow (identified by, e.g., a 5-tuple) and trigger synchronized reporting when predefined traffic thresholds are met. By including physical entity identifiers (e.g., lineCardId, portId) and the newly defined energy Information Elements, the exporter can generate multiple correlated data records corresponding to the various physical interfaces involved in forwarding the flow. This enables collectors to reconstruct a complete, multi-path energy footprint of the flow across the device, supporting accurate per-flow energy cost attribution and operational analysis.

Relationship to GREEN WG Work and Other Telemetry Mechanisms

Positioning within the GREEN Framework The IPFIX energy telemetry mechanism defined in this document is recommended as a protocol-specific supplement to the GREEN WG energy efficiency management framework , targeting monitoring use cases that require tight coupling of traffic and energy metrics. To support uniform data aggregation and analysis across different telemetry protocols, it is RECOMMENDED to align the semantic definitions of energy metrics with the GREEN Power and Energy YANG module .

The YANG module paired with YANG Push provides a general-purpose telemetry solution for device and component energy monitoring, typically used for network-wide energy status collection, long-term trend analysis, and lifecycle energy management.
The IPFIX IEs defined in this document enable traffic-event-driven energy telemetry, which is RECOMMENDED for scenarios where energy measurements need close time alignment with traffic observations.

Complementarity with YANG Push IPFIX-based energy telemetry and YANG Push-based telemetry are both viable implementation options for energy efficiency monitoring under the GREEN framework, with different design focuses and applicable scenarios.

YANG Push telemetry is a general telemetry approach built on the YANG data model, with unified semantic specifications and flexible subscription capabilities. It is RECOMMENDED for full-coverage energy monitoring of network-wide devices and components, lifecycle energy management, and cross-domain energy efficiency data aggregation.
IPFIX-based energy telemetry is a traffic-oriented telemetry extension leveraging IPFIX's native flow metering capabilities. It is RECOMMENDED for scenarios requiring deep association between energy data and traffic flows or traffic events.

For operators with both general device monitoring and fine-grained traffic-related analysis requirements, it is advisable to deploy both mechanisms in a complementary manner.

Operational Considerations The export and interpretation of energy consumption information in IPFIX are intended to be driven by traffic activity observed at specific points in the data plane. Implementations SHOULD configure monitoring policies that associate one or more physical entities, such as a device, line card, or port—with an observation object (e.g., an interface or a flow). Energy telemetry records SHOULD be generated when predefined traffic-driven conditions are met. These conditions MAY include:

The number of packets observed since the last export exceeds a configured threshold;
An active timeout elapses under continuous but low-volume traffic; or
An inactive timeout elapses after no packets are observed for a configured duration.

The Exporting Process collects power measurements—such as instantaneous and average power—for each associated physical entity. These measurements are encoded into Data Records using the newly defined energy Information Elements (e.g., lineCardRealtimePower, portAveragePower). Each Data Record SHOULD also include identifier Information Elements (e.g., lineCardId, portId) to unambiguously associate the reported power values with their corresponding hardware components. The resulting Data Records are exported to a Collector within an IPFIX Message, along with a reference to the applicable Template Record (e.g., via Template ID). A Collector receiving such messages SHOULD possess the corresponding Template Record to correctly parse the structure and semantics of the Data Records. The Collector parses each Data Record to recover:

The identifier(s) of the physical entity (or entities) linked to the observation object; and
The associated energy consumption information.

This end-to-end mechanism ensures that energy reports are causally tied to traffic activity.

Security Considerations TBA

IANA Considerations This document requests IANA to create a new IE under the "IPFIX Information Elements" registry available at . IPFIX Information Elements Registry

Element ID	Name	Reference
TBD1	deviceRealtimePower
TBD2	deviceAveragePower
TBD3	lineCardRealtimePower
TBD4	lineCardAveragePower
TBD5	portRealtimePower
TBD6	portAveragePower

Acknowledgements TBA