Alvaro Retana's No Objection on draft-ietf-bfd-multipoint-18: (with COMMENT)

[Alvaro Retana <[e-mail]>]

Alvaro Retana has entered the following ballot position for
draft-ietf-bfd-multipoint-18: No Objection

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COMMENT:
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(1) This document is marked as Updating rfc5880, buy §4.1 (in rfc5880), still
has this text:

Multipoint (M)

   This bit is reserved for future point-to-multipoint extensions to
   BFD.  It MUST be zero on both transmit and receipt.

...which should also be addressed in this document.

(2) §5.3. (Session Failure Semantics): "If a MultipointTail session fails...the
tail should take appropriate action."  What is an "appropriate action"?  I'm
guessing that this has to do with I-D.ietf-bfd-multipoint-active-tail, but that
only applies if a return path exists.  In the general case, should the tail
take any action?  Please clarify.

(3) §5.7 and §5.13.2 talk about "the identity of the multipoint path" -- what
is that?

(4) §5.13.2:

   If a session is not found, a new session of type
   MultipointTail MAY be created, or the packet MAY be
   discarded.  This choice MAY be controlled by the local
   policy, e.g. a maximum number of MultipointTail sessions and
   number of active MultipointTail sessions, and is outside the
   scope of this specification.

I think the last "MAY" above is out of place (s/MAY/may): if local policy
doesn't exist, what is the option?  The text says that this topic is outside
the scope...but I'm not sure if that means the local policy or the choice
itself.  §8 (Security Considerations) offers some more insight...but it doesn't
explicitly specify a limit to the number of MultipointTail sessions -- should
one exist?

The text above also calls out the "number of active MultipointTail sessions" as
if it were something different (from simply the number of MultipointTail
sessions), but this difference is not explained or mentioned anywhere else.  Is
there a difference?  Is there a need to call this out?

(5) Nit:  Please don't abbreviate to "My Discr" and "Your Discr".