Last Call Review of draft-ietf-lsr-isis-fast-flooding-07
review-ietf-lsr-isis-fast-flooding-07-tsvart-lc-kuehlewind-2024-02-29-01

This document has been reviewed as part of the transport area review team's
ongoing effort to review key IETF documents. These comments were written
primarily for the transport area directors, but are copied to the document's
authors and WG to allow them to address any issues raised and also to the IETF
discussion list for information.

When done at the time of IETF Last Call, the authors should consider this
review as part of the last-call comments they receive. Please always CC
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I did an early TSV review a few weeks ago and the current version addresses a
lot of the comments and is an improvement.

On the high level I still think the document can be further improves by
recommending and discussion appropriate default values or values ranges to
ensure safe operation as implementors often reply on default value and if no
recommendation is given or discussed this can lead easy to a selection of too
high values that would overload the other end.

Also the congestion control part seems rather complex for a point-to-point
connection. I understand that the proposed mechanism was experimented with and
showed improvements in case of overload of the internal switch. However,
congestion control usually also aims to fully utilise the available resources
which is not a goal here and therefore a simpler solution like a circuit
breaker would probably be sufficient.

Update: Even though the last review was meant to be an "early" it was only
requested right before IETF LC. I understand that the feedback provided is
therefore rather late in the process and therefore I don't think should block
publication of the draft.