**Session Date/Time:** 06 Nov 2023 16:30

# grow

## Summary
The grow session at IETF 118 covered several topics including BGP community modeling, updates to BCP 194, and updates to BMP. Discussions involved the structure and publication of BGP communities, security and operational best practices for BGP, and the addition of new statistics to BMP. Calls for working group adoption were issued for several drafts.

## Key Discussion Points

*   **BGP Community Modeling (Martin Pills):**
    *   Discussion about modeling BGP communities using a YANG model to provide a structured way to publish and automate BGP community definitions.
    *   Considerations included the encoding of various types of information within communities (e.g., country codes, peer ASNs).
    *   Challenges were raised regarding handling token boundaries and bit-level encodings in existing communities.
    *   Deterministic parsing and ordering of patterns were discussed to ensure proper community matching.
*   **BCP 194 Update (Tobias):**
    *   Review of proposed updates to BCP 194, covering BGP operational security best practices.
    *   Discussion of terminology unification, newer attack vectors, IXP considerations, and filtering techniques.
    *   Emphasis on import filtering and mitigating potential issues related to prefix limits and AS path lengths.
    *   Consideration of algorithmic complexity in rule generation and ordering.
    *   Debate on whether recommendations should be "must" or "should" and whether IBGP filtering is going too far.
*   **BMP Updates (Paolo):**
    *   **Route Mirroring splitting registries**  Draft discussed splitting the init and pickup registries.
    *   **Support for TLVs:** The major discussion point was the move to putting BGP PDUs into TLVs, with associated discussions regarding indexing and stateless parsing. Version was bumped to 4.
    *   **EBIT Support:** Discussion and progress on adding EBIT support for TLVs.
    *   **Route Event Logging (REL):** A new BMP message type for event-driven reporting and alerting.  The discussion focused on the format and content of policy discard information, specifically how the data should be structured for useful alerting and reporting.
*   **BMP Statistics (Jeff Haas):**
    *   Proposal to add additional statistics (rib in and rib out gauges) into BMP, providing telemetry data about the state of the router.
    *   Discussion included the types of statistics to include (e.g., rejected routes, accepted routes, active routes, stale routes) and the cadence at which these statistics should be emitted.
*   **Local Pass ID (Maxime and Pierre):**
    *   Introduction of a new draft proposing the use of a local path ID to uniquely identify paths within a router and report it in BMP.
    *   Discussion of requirements for the ID, including uniqueness, preservation across VRFs, and avoidance of interprocess communication.
    *   Concerns were raised about the additional state required to track path IDs.

## Decisions and Action Items

*   **BGP Community Modeling:** Issue a call for working group adoption in the next few days.
*   **BCP 194 Update:** Issue a call for working group adoption in the next few days.  Participants were encouraged to file issues on GitHub to track specific recommendations or opinions.
*   **BMP Updates:**
    *   Paolo to process comments from Luke and others related to TLV designs for BMP.
    *   Paolo to process existing feedback, including recent code issues, and incorporate them into the draft.
    *   Route Event Logging: Working group adoption call is ongoing.
*   **BMP Statistics:** Initiate a call for working group adoption.
*   **Local Pass ID:**  Authors to consider feedback on the additional state required for tracking the path ID, and revisit the approach if improvements are possible.

## Next Steps

*   Issue calls for working group adoption for the BGP Community Modeling, BCP 194 Update, and BMP Statistics drafts.
*   The next IETF grow session will be in Bristol.