**Session Date/Time:** 18 Mar 2024 05:30

# bier

## Summary
The BIER working group meeting covered several topics, including document shepherd status updates, presentations on BGP extensions for BIER, redundant ingress router failover, a novel implementation of BIER using segment encoding (SEED), an interoperability test report from EANTC, and a proposal for Anycast MPLS labels for fast failure recovery. A key discussion revolved around the publication of informational drafts, including the BIER requirements document.

## Key Discussion Points

*   **Document Shepherd Shortage:** There is a significant shortage of shepherds for BIER documents. Several drafts are in the queue awaiting shepherd review.
*   **BGP Extensions for BIER:** A presentation covered BGP extensions for disseminating BIER-specific information.
*   **Redundant Ingress Router Failover:** A draft focusing on redundant ingress router failover scenarios was presented, highlighting the use of BIER-specific technologies for candidate UMH (Upstream Multicast Hop) failure detection.  The group decided to delay a last call to incorporate new work on DF (Designated Forwarder) election.
*   **Segment Encoded Explicit Trees (SEED):** A novel implementation of BIER using segment encoding was presented. It combines traffic engineering capabilities with efficient replication via BIER, particularly beneficial in large networks with smaller bit string lengths. The authors were encouraged to submit a draft for further discussion and collaboration within the working group.
*   **EANTC Interoperability Test Report:** A report from EANTC highlighted successful interoperability testing between different vendors' BIER implementations, demonstrating the ability to forward BIER packets with a 256-bit header across transit routers. ECMP and NGM VPN overlay were not tested due to time constraints.
*   **Anycast MPLS Label for Fast Failure Recovery:** A new method for fast failure recovery using Anycast and bypass MPLS labels within BIER domains was presented. Some participants found the need for this solution unclear given existing fast convergence technologies in IGP.
*   **BIER Requirements Document:** A discussion arose regarding the publication of BIER requirements documents as informational RFCs to preserve the historical context and rationale behind design decisions. There were mixed views on whether to proceed with this, and the AD suggested further discussion within the IESG.
*   **IOM Encapsulation:** A draft related to IOM encapsulation over BIER was discussed. It relies on another draft related to BIER extended headers, which the group may move to adopt pending list review.

## Decisions and Action Items

*   **Redundant Ingress Router Failover Draft:** Hold off on working group last call for the redundant ingress router failover draft until the mechanism for DF election is more complete.
*   **SEED Implementation:** The authors of the SEED implementation will submit a draft version of their work to the mailing list for further discussion and potential adoption.
*   **BIER Extended Headers Draft:** Consider adoption of the draft relating to BIER extended headers on the mailing list.
*   **BIER Requirements Document:** Discuss the possibility of publishing BIER requirements documents as informational RFCs with the incoming AD (Gunther) and within the IESG.
*   **Anycast MPLS Label:** Seek further justification of the benefits of the Anycast MPLS Label draft before adoption.

## Next Steps

*   The BIER working group will further discuss the proposed Anycast MPLS Label draft on the mailing list.
*   The chair will follow up with the AD regarding the publication of historical requirements documents.
*   Authors are encouraged to submit drafts of their presentations for consideration as working group documents.
*   The working group will review the draft on BIER Extended Headers.