**Session Date/Time:** 28 Jan 2025 17:00

# [LAKE](../wg/lake.html)

## Summary

This interim meeting of the LAKE Working Group covered updates on several adopted drafts (GREASE, ODS, AP-PROFILES, PSK), formalized the adoption of the LAKE-RA draft, and discussed planning for IETF 122. A significant announcement was the transition of co-chairmanship from Stephen Farrell to Renzo Comin.

## Key Discussion Points

*   **Co-chair Transition:** Stephen Farrell stepped down as co-chair, and Renzo Comin officially joined as the new co-chair. The working group thanked Stephen for his contributions.
*   **GREASE (draft-ietf-lake-grease) Update:**
    *   The document was recently adopted. Its purpose is to exercise EDHOC extension points to prevent them from becoming ossified.
    *   Two main questions arose during the adoption call:
        1.  Whether better mechanisms can be implemented for greasing cipher suites, especially given that only the initiator might be a constrained device. The current protocol simplicity might limit flexibility here.
        2.  How to exercise the extension point for ad-hoc authentication credential types within a COSE header map. Uncertainty exists regarding the semantics of unknown items in COSE header maps – specifically, if they are mandatory to understand or can be ignored by default. If they cannot be ignored, greasing would break functionality, defeating its purpose.
    *   Christian expressed willingness to run interoperability tests, noting that current EDHOC implementations would likely fail.
    *   An email discussion on the mailing list has been initiated to gather input on these questions.
*   **ODS (draft-ietf-lake-ods) Update (on behalf of Jovan Marojevic):**
    *   The intent is to broaden the scope of the draft to cover generic notarization of ad-hoc rather than being constrained only to the enrollment use case.
    *   Proposed changes include:
        *   Adding a new subsection in Section 4 to generically describe the protocol in both forward and reverse flows.
        *   Moving the network enrollment use case to a dedicated Section 5.
        *   Instantiating optimization strategies from the current draft within the enrollment use case.
    *   These next steps were supported by Christian.
*   **Application Profiles (draft-ietf-lake-ap-profiles) Update:**
    *   The draft was adopted and is undergoing editor's copy work on GitHub, targeting a version 1 revision for IETF 122.
    *   Updates in the editor's copy include:
        *   Moving definitions of several information elements (e.g., COAP-CF corrected to COAP-CT, URI-PATH) to the ACE WG's `draft-ietf-ace-cose-info-obj`, as they pertain better to the COSE Information Object.
        *   The `AProf` parameter definition remains in this document.
        *   Incorporated features from `draft-ietf-lake-ta-hint` related to advertising supported trust anchors (references only, not values), defining a corresponding `trust-anchors` parameter and link target attributes.
    *   A major point of work is on advertising supported EDHOC features and profiles *within* EDHOC messages themselves. This includes using a new EAD item for EDHOC Message 1 and 2, and a new error code/info for an EDHOC error message in reply to Message 1. This EAD item will be a COER sequence (byte string wrapping a COER sequence for Msg1/Msg2) or directly a COER sequence (for error messages), capable of conveying profile identifiers, arrays of EAD labels, or piece-by-piece indication of supported features via an EDHOC Information Object.
*   **PSK (draft-ietf-lake-psk) Update:**
    *   The draft was adopted and has undergone several corrections and clarifications.
    *   PSK1 variant has been removed, only PSK2 remains.
    *   Corrections include: adding hyperlinks, referencing concepts and terms, reformulating `ID_cred_PSK` and `Cred_PSK` definitions, correcting a typo in `K_SK_3` derivation (key length vs. credential identifier length), and a title change for Section 5.
    *   A key point of discussion is the structure of Ciphertext 3 in EDHOC Message 3. Two options are being considered:
        1.  Defining Ciphertext 3 as a COER sequence composed of two elements (`Ciphertext_3A` and `Ciphertext_3B`). This would be a deviation from RFC 9528.
        2.  Defining Ciphertext 3 as a COER sequence of one element (which itself is a COER sequence composed of two elements), implying an extra wrapping that adds bytes.
    *   Marco expressed support for Option 1, despite it being a deviation, provided it is clearly highlighted.
*   **LAKE-RA (draft-ietf-lake-ra) Adoption Call Summary:**
    *   The adoption call concluded, with a clear sense of consensus for adoption.
    *   Comments were received from Michael Richardson and the RATs Working Group, which included technical remarks.
*   **IETF 122 Planning (Bangkok):**
    *   A poll of those present indicated that while many would be attending remotely, several key contributors (e.g., Marco, Richard, John) plan to be on-site.
    *   A sense of those present was to request a physical meeting for IETF 122.
*   **CDDL Rata for EDHOC:**
    *   A rata for the EDHOC CDDL was submitted by Brian Seos. Discussion on this will be pursued on the mailing list.

## Decisions and Action Items

*   **Decision:** Stephen Farrell stepped down as co-chair, Renzo Comin officially takes over as co-chair.
*   **Decision:** `draft-ietf-lake-ra` is adopted as a Working Group document.
*   **Decision:** The chairs will request a 1-hour hybrid session for the LAKE Working Group at IETF 122 in Bangkok.
*   **Action Item (Christian):** Continue email discussion on the mailing list regarding GREASE questions (semantics of COSE header map elements).
*   **Action Item (Christian):** Run interoperability tests for GREASE, particularly to observe potential breaking changes.
*   **Action Item (Jovan):** Update `draft-ietf-lake-ods` to reflect generic notarization, including new sections for generic protocol flow and dedicated enrollment use cases.
*   **Action Item (Marco):** Prepare `draft-ietf-lake-ap-profiles` version 1, focusing on in-message advertisement of profiles/features and addressing adoption call comments.
*   **Action Item (Ela and PSK authors):** Conduct another round of protocol review for `draft-ietf-lake-psk`, aiming for a stable version by IETF 122, before calling for formal analysis.
*   **Action Item (Chairs):** Send an official announcement on the mailing list regarding the adoption of `draft-ietf-lake-ra`.
*   **Action Item (Yuan):** Lead discussions to address technical comments received from Michael Richardson and the RATs Working Group for `draft-ietf-lake-ra` once the `ietf-lake` version is published.
*   **Action Item (Yuan):** Pursue discussion on the mailing list regarding the submitted CDDL rata for EDHOC.

## Next Steps

*   Continue working on GREASE, ODS, AP-PROFILES, and PSK drafts to address open questions and incorporate feedback.
*   Formal analysis of `draft-ietf-lake-psk` will be initiated once the protocol is deemed stable by the authors.
*   The LAKE Working Group will meet for a 1-hour hybrid session at IETF 122 in Bangkok.
*   Discuss and resolve the CDDL rata on the mailing list.
*   Address comments on `draft-ietf-lake-ra` after its publication as a WG draft.