**Session Date/Time:** 21 Jul 2025 10:00

# Green Working Group Session

## Summary

The Green Working Group held its first session focusing on three draft documents for potential adoption and related work presentations. The session covered liaison statements from other standards organizations, draft presentations on use cases, terminology, and framework documents, along with two presentations on energy-aware routing work from other working groups. The chairs emphasized the importance of mailing list participation to support adoption decisions and outlined plans for interim meetings and hackathon discussions in the following session.

## Key Discussion Points

### Liaison Statements
- Received liaisons from W3C regarding coordination on energy efficiency activities
- ITU-T and ETSI provided replies to the working group's introductory liaison statement, pointing to relevant ongoing work
- Chair offered to share summaries of liaison responses on the mailing list

### Draft Presentations

#### Use Cases Document (draft-ietf-green-use-cases)
- Document updated to version 2 with improved template structure
- Framework material moved to separate framework document
- Two new use cases added, with emphasis on double counting risk issues
- Previous adoption poll was unsuccessful due to insufficient mailing list support
- Virtual poll showed reasonable number of participants had read the document
- Plans for second adoption poll after the meeting

#### Terminology Document (draft-ietf-green-terminology)
- Presented by Qin Wu with multiple co-authors including new contributor Slash
- Document has been around since IETF 121-122, presented at recent interim meetings
- Version 04 adds new section on operational management considerations
- Five new energy efficiency terms added based on interim meeting feedback
- 70+ terms currently defined, focusing on key terminology and reusing existing IETF definitions
- GitHub repository established for tracking open issues
- Strong support shown in adoption poll (24 yes votes)

#### Framework Document (draft-ietf-green-framework)
- Relatively new document (first version posted in May) by Benoit and co-authors
- Presents architecture covering network domain level down to individual components
- Addresses power distribution topology discovery challenges
- Introduces concepts of power source relationships, energy objects, and metering relationships
- Discusses device capabilities, power states, and intent mapping
- Highlights issues with double counting in energy measurements
- Multiple open issues identified including capability discovery and SLA considerations
- Document considered potentially good basis for framework but premature for adoption

### Technical Discussion Points
- **Energy efficiency vs. energy usage metrics**: Joe Clark raised concerns about clarity between measuring efficiency improvements over time versus general energy consumption
- **Power distribution topology**: Unlike network topology, power distribution cannot be discovered through CDP/LLDP, requiring explicit metering relationships
- **Double counting prevention**: Critical issue when aggregating energy consumption across components with power dependencies
- **Device capabilities and power states**: Need for standardized discovery mechanisms and clear definitions of power state implications

### Related Work Presentations

#### Energy-Aware QoS Integration
- Ruth Sophia presented draft on integrating energy metrics into QoS models
- Proposes using DiffServ as representative QoS model with energy awareness
- Targets telco cloud environments with multi-tenant considerations
- Suggests experimental code points for energy-sensitive traffic
- Work considered out of scope for Green WG but of broader IETF interest
- Virtual poll showed support (30 yes) for progressing work within IETF

#### Energy Efficiency Routing
- Jin Ming He presented work on energy consumption aware routing
- Focuses on IGP and BGP protocol extensions for energy data collection
- Proposes three-step process: indicator definition, data collection, path calculation
- Work primarily targeted at LSR, IDR, and Spring working groups
- Includes threshold mechanisms to prevent frequent path switching

## Decisions and Action Items

### Adoption Decisions
- **Terminology document**: Strong in-room support for adoption, to be confirmed on mailing list
- **Use cases document**: Second adoption poll to be conducted on mailing list after meeting
- **Framework document**: Not ready for adoption but recognized as potential future candidate

### Action Items
- Chairs to conduct mailing list adoption polls for terminology and use cases documents
- Participants encouraged to respond to mailing list polls to demonstrate support
- Framework document links to be shared in chat for review
- Chair to potentially share liaison response summaries on mailing list
- Energy-aware QoS work to be discussed with area directors for potential IETF progression path

## Next Steps

- **Terminology document**: Mailing list confirmation of adoption decision
- **Use cases document**: Second adoption cycle with mailing list poll
- **Framework document**: Encourage community review and feedback, discuss open issues in tomorrow's session
- **Interim meetings**: Plans for additional informal interim meetings going forward
- **Tomorrow's session**: Focus on hackathon recap, new draft proposals, and detailed discussion of modeling work and framework open issues
- **Related work coordination**: Continue liaison activities with other SDOs and working groups

The session emphasized the importance of mailing list participation to ensure adoption decisions reflect genuine community support beyond in-room polls.

---

**Session Date/Time:** 22 Jul 2025 15:00

```markdown
# green

## Summary

This session focused on data models for energy efficiency and sustainability in networking. Presentations were given on drafts related to utilization scores in ISAAC, energy consumption per path (PETRA), and transport network use cases. A hackathon update highlighted practical implementations and data collection. The session also discussed next steps for developing a base data model, including a lightweight design team approach. Open modeling questions were addressed, and consensus was sought on key areas such as granularity of power control, accuracy of information, and time intervals for reporting data.

## Key Discussion Points

*   **ISAAC Utilization Scores:**  Discussion on how the ISAAC model fits into the broader working group charter and how it can be extended from a base Yang model.
*   **PETRA API:** Proposal to place PETRA as another API from the controller to get information per path. Questioned whether this should be a general query API or specifically for on-radio networks, and how it fits within the scope of green.
*   **Transport Network Use Cases:** Presentation on transport-specific barriers and proposed use cases for network-level optimization with multilayer energy-saving management.
*   **Hackathon Update:** Report on collecting metrics from different devices (routers, smart PDUs) and integrating them using the framework document. Used a video streaming use case for end-to-end consumption reporting.
*   **Design Team Formation:** Discussed the formation of a lightweight design team to focus on base data model development through regular interim meetings.
*   **Modeling Granularity:** Discussed granularity for control and reporting of power use, also addressing power states (E-Work states, ranges, framework document power states).
*   **Reporting Accuracy:** How to report the accuracy of energy usage metrics. Do we need to indicate dynamically the level of accuracy for reporting information?
*   **Reporting Time Intervals:** What time intervals should the data be reported over? Does this have to be in stone or up to the device to determine?
*   **Network vs. Device Level:** Need to design the Yang models for both network level and device levels for energy reporting.
*   **Customer Use Cases:** Discussion of what's covered and what is the aim to report to customer as end users

## Decisions and Action Items

*   **Lightweight Design Team:** Agreed to proceed with a lightweight design team consisting of regular interim meetings chaired by Rob or Diego.
*   **GitHub Repository:** Set up a GitHub repository for collaborative model development, issue tracking, and discussion.
*   **Adopt Existing Documents:** Pursue adoption calls for the use cases and terminology drafts.
*   **Liaison:** Leveraging existing Liaison statements
*   **Base Model Iteration:** Jan will start writing a base model draft for discussion within the design team and broader working group.
*   **Continue Modeling Discussions:** Continue discussions on open modeling questions, particularly related to granularity, accuracy, and time intervals. Send conclusions to the list
*   **Offline Customer Discussion:** Discuss the customer-facing aspects of reporting and guidance offline

## Next Steps

*   Poll working group for scheduling the lightweight design team interim meetings.
*   Establish the GitHub repository.
*   Review and leverage relevant liaison statements.
*   Begin adoption calls for use cases and terminology drafts.
*   Commence development of the base data model draft in Yang.
*   Share detail about the separation on device and network levels of reporting, as well as what the requirements are with those to the list.
```