Last Call Review of draft-ietf-mpls-bfd-directed-27
review-ietf-mpls-bfd-directed-27-opsdir-lc-clarke-2024-04-12-00

I have been asked to review this document on behalf of the OPS directorate. 
While overall, I found the document readable and clear, I do have a few
comments and a question, so I chose a state of Has Nits.  However, I feel it is
mostly ready.  I also appreciate the Operational Considerations section and the
additional MTU text suggested by Andrew.

One comment I have is around terminology and abbreviations.  I know this is an
mplswg document, but you did expand BFD and LSP.  I think it would be helpful
to expand FEC and LSR, too.

The other comment I have is around use ingress and egress "BFD peer".  I like
this terminology, but you have cases in Section 1 where you use ingress and
egress BFD "system".  In Section 3.1, you mix in "egress LSR".  In Section 5,
you mix in "ingress BFD node".  I would suggest consistent terminology.  I like
peer and peer LSR also works for me.

On that topic, thank you for the example in Section 4.  I would just add that
perhaps you label or describe node A as the ingress BFD peer [LSR] and H as the
egress BFD peer [LSR].  It would help tie the figure to the rest of the text.

Finally, my question.  In the Operational Consideration, what would (or should)
happen to the underlying service while the LSP ping is processed in the case of
reverse-path FEC failure?  Is there guidance to provide to maintain service
while this new session might be established?