Session Date/Time: 21 Mar 2024 03:00

lsr

Summary

The LSR working group session covered a range of topics, including working group document status, updates on ongoing drafts, and presentations of new proposals. Key discussions revolved around the adoption of drafts related to multi-part TLVs, querying router implementation details, source address verification, signaling aggregate header size limits, advertising multi-interface ID for L2 bundle members, scheduled metric changes for TBR, colored IP prefix, and using FlexAlgo for SR-based ARPs, each with its own set of considerations and concerns.

Key Discussion Points

Multi-part TLVs: The draft is proposed for working group last call, emphasizing the need for implementations to provide controls to prevent or deal with partial deployment.
Router Implementation Details: A draft aiming to query router implementation tires of protocols was discussed. The working group agreed to adopt it.
Source Address Verification: A method for source address verification in intra-domain networks was presented, which led to a discussion on protocol extensions.
Signaling Aggregate Header Size Limits: A proposal to signal aggregate header size limits via IGP extensions sparked concerns about the IGP acting as a "dump truck" and the complexity of IPv6 extension headers. Suggestion to move discussion to 6man WG.
Advertising Multi-interface ID for L2 Bundle Members: A draft that would help network operators to control traffic by advertising the local and remote interface IDs for a true boundary member in ITP. The draft will add the other use case beside discovery by the controller.
Scheduled Metric Changes for TBR: A presentation discussing HP extensions for TBR encountered resistance, with concerns about diverging from the TBR working group's direction (Yang model distribution) and overloading the IGP.
Colored IP Prefix: Presenting colored IP prefix as an enhancement to IDB's shortcut. The group discussed if tags could also be used for this purpose.
FlexAlgo for SR-based ARPs: A proposal using FlexAlgo for SR-based ARPs faced scrutiny regarding potential conflicts with existing l2 bundles and the best path metric types.

Decisions and Action Items

Adopted: The working group agreed to adopt the draft on querying router implementation details.
Last Call: The draft on multi-part TLVs is likely to be put forward for working group last call soon.
Hold/Revise: The draft on FlexAlgo for SR-based ARPs should be put on hold until there's consensus on key issues, and discussions should continue in both LSR and TEAS working groups. The e-bit discussion will be continued on the mailing list.
Mailing List Discussion: Further discussion on the distribution of schedule information for TBR and whether it should go into the IGP will be conducted on the TBR mailing list, with LSR CC'd.
Update Draft: Authors of the 'advertising multi-interface ID' document to add another use case that has been discussed in the group, beside discovery by the controller.
Update Draft: Authors of the 'IGP flash algo with link loss' to add a description stating that it is a good guideline to have a similar method for the Flex Algorithm.

Next Steps

Move forward with working group last call for the multi-part TLV draft.
Initiate adoption call for the draft on router implementation details.
Continue discussions and revisions on drafts related to FlexAlgo for SR-based ARPs, TBR extensions, and other topics based on the feedback received.
Consider operational guidance document on using Link Loss as a Flex Algorithm constraint