**Session Date/Time:** 06 Oct 2025 13:00

# [GREEN](../wg/green.html)

## Summary

This informal virtual interim meeting of the GREEN Working Group aimed to kickstart progress on data model development. Key discussions revolved around the proposed structure and prioritization of data model work, collaboration tooling, and administrative aspects for future meetings. Agreement was reached to focus initial data model development on controller-side aspects, utilize a GitHub-based collaborative toolchain, and transition to WebEx for future meetings. The chairs also committed to re-initiating adoption calls for the use cases and terminology drafts.

## Key Discussion Points

*   **Meeting Format and Cadence:** The meeting was held as an informal virtual interim, envisioned as a hybrid between interim and design team meetings. The plan is to hold these roughly weekly leading up to IETF 124, adjusting cadence based on participant feedback. More formal interims will be scheduled monthly or bi-monthly for broader progress reports.
*   **IETF Note Well and Code of Conduct:** A reminder was given that all contributions fall under the IETF Note Well, and respectful conduct is expected from all participants.
*   **Progress from IETF 123:**
    *   Ongoing liaison steps and identification of work to leverage.
    *   Re-initiation of adoption polls for `draft-ietf-green-use-cases` and `draft-ietf-green-terminology`.
    *   Continued progress on framework documents in parallel with data model work.
    *   The core focus of these lightweight virtual interims is making progress on the data models.
*   **Data Model Focus (Jan's Proposal):**
    *   **Goal:** Define simple YANG models for energy data at device, component, and network levels, identify common groupings/metrics, and consider impacts from the framework document (without strict conformance). The aim is to establish common base structures, allowing for future augmentations.
    *   **Collaboration:** A GitHub repository (`green-design-work` proposed) will be used for collaborative draft work. Jan has agreed to act as an editor for the data model draft(s). The main GREEN WG mailing list will be used for discussions, with GitHub for issue tracking.
    *   **Output:** The design team's output will initially be individual draft(s) requiring a standard WG adoption process.
    *   **Work Item Prioritization:** Jan presented a proposal for prioritizing work items:
        1.  **Work Item 1 (Controller-side):** Collection, aggregation, delivery, Query API (e.g., best path, cost of something from controllers). Proposed initial focus (approx. 60% effort).
        2.  **Work Item 2 (Device-side):** Measurement, reporting, control, configuration. Proposed secondary focus (approx. 30% effort), run in parallel.
        3.  **Work Item 3:** Energy-aware protocol extensions (e.g., for routing, path computation).
        4.  **Work Item 4:** Other (e.g., energy consumption prediction, accounting, billing).
    *   **Discussion on Prioritization:** A sense of those present indicated support for Jan's proposal to prioritize Work Item 1, recognizing it as a less explored and central area, while advancing Work Item 2 in parallel. The ultimate goal is for Work Items 1 and 2 to complete around the same time.
*   **Tooling for Collaboration:**
    *   Rob demonstrated a local toolchain that integrates Markdown for narrative text with YANG models, providing real-time compilation, YANG tree diagrams, and validation. The toolchain aims for compatibility with Martin Thompson's standard IETF build tools.
    *   Jan expressed willingness to experiment with the proposed toolchain, emphasizing the importance of Martin Thompson's infrastructure compatibility.
    *   GitHub Issues will be used for tracking open items and discussions.
*   **Meeting Platform:** Discussion around using Meet Echo versus WebEx for future informal meetings. Concerns were raised about Meet Echo's manual calendar invite process.
*   **IETF 124 Planning:** A preliminary agenda indicates GREEN WG sessions on Monday (short) and Friday (long). A proposal was made to dedicate the Monday session to main document discussions and potentially use the Friday session for a design team-focused meeting.
*   **Status of Existing Documents (Use Cases, Terminology, Framework):**
    *   Marisol inquired about the call for adoption status for `draft-ietf-green-use-cases`, `draft-ietf-green-terminology`, and `draft-ietf-green-framework`.
    *   The chairs acknowledged the need to re-kick off adoption calls for the use cases and terminology drafts, noting previous challenges with reviews for the use cases document.
    *   For the framework document (currently v5), the chairs suggested presenting an update at IETF 124. They proposed deferring an adoption call until the document has further evolved, to allow flexibility for changes in parallel with data model development.
*   **IEEE-IETF Coordination:** Mahesh highlighted coordination efforts with IEEE. He asked if there are any aspects of GREEN WG work, particularly regarding interface management or power usage (relevant to IEEE 802.3, 802.15), that IEEE should be made aware of for potential specification. The initial sense was that GREEN models aim to be generic, but it's worth adding a periodic touchpoint to track if any specific IEEE instrumentation needs arise as data models evolve.

## Decisions and Action Items

**Decisions:**

*   **Data Model Focus:** Agreement to proceed with Jan's proposed prioritization for data model work, with an initial primary focus on Work Item 1 (Controller-side) while progressing Work Item 2 (Device-side) in parallel.
*   **Meeting Platform:** Future informal interim/design team meetings will use WebEx to improve ease of interaction and calendar management.
*   **Document Adoption:** The chairs will re-initiate adoption calls for the `draft-ietf-green-use-cases` and `draft-ietf-green-terminology` drafts.

**Action Items:**

*   **Jan:**
    *   Experiment with Rob's proposed GitHub/toolchain setup for collaborative data model development.
    *   Start drafting initial YANG models for Work Item 1 (Controller-side).
    *   Provide input on Work Items 1 and 2 to the mailing list.
*   **Rob:**
    *   Share the GitHub repository link and toolchain details with Jan, including addressing Windows compatibility issues.
    *   Schedule future GREEN WG informal meetings on WebEx and manage calendar invites.
    *   Discuss the framework document's readiness for adoption with co-chair Diego after its IETF 124 presentation.
*   **Daniel:**
    *   Review existing GREEN WG Use Cases document.
    *   Provide a high-level description of his data center use case, highlighting any gaps against current GREEN WG models, to the mailing list.
*   **Chairs (Rob & Diego):**
    *   Re-initiate adoption calls for `draft-ietf-green-use-cases` and `draft-ietf-green-terminology`.
    *   Engage with framework document authors to plan for IETF 124 presentation and discuss future adoption strategy.
*   **WG Participants:** Provide opinions on Work Items 1 and 2 on the mailing list to guide Jan's initial drafting.
*   **Mahesh:** Continue tracking potential coordination points with IEEE regarding power usage specifications in their standards, adding it as a periodic check-in item.
*   **Benoit:** Provide a list of existing open issues for the framework document that are relevant to the data model work items.

## Next Steps

*   The next informal virtual interim meeting will be held in one week.
*   Jan will begin developing initial YANG models for Work Item 1 based on the agreed-upon focus.
*   Participants are encouraged to engage on the mailing list with opinions regarding Work Items 1 and 2 to facilitate progress.
*   Authors of existing drafts (Use Cases, Terminology, Framework) should prepare for IETF 124, with the framework document expected to present an update.