Eric Rescorla's No Objection on draft-ietf-bfd-multipoint-active-tail-09: (with COMMENT)

[Eric Rescorla <[e-mail]>]

Eric Rescorla has entered the following ballot position for
draft-ietf-bfd-multipoint-active-tail-09: No Objection

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COMMENT:
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Rich version of this review at:
https://mozphab-ietf.devsvcdev.mozaws.net/D3976



COMMENTS
S 5.2.3.
>      (regardless of the state of the forward unicast path), the tail will
>      detect the failure but the head will remain unaware of this fact.
>   
>      The head will detect a BFD session failure to the tail but cannot
>      make a determination about the state of the tail's multipoint
>      connectivity.

This seems to contradict the paragraph two above "If the multipoint
path fails". Or am I misreading?


S 5.2.3.
>      connectivity.
>   
>      If the forward unicast path fails but the reverse unicast path stays
>      up, the head will detect a BFD session failure to the tail if it
>      happens to send a unicast Poll sequence, but cannot make a
>      determination about the state of the tail's multipoint connectivity.

This doesn't seem right if the multicast path works.


S 6.4.
>      [I-D.ietf-bfd-multipoint], in which BFD Control packets flow only
>      from the head and no tracking is desired of tail state at the head,
>      is accomplished by setting bfd.ReportTailDown to 0 in the
>      MultipointHead session (Section 5.1).
>   
>      If the head wishes to know of active the tails, it sends multipoint

This is ungrammatical.


S 6.5.
>   6.5.  State Machine
>   
>      Though the state transitions for the state machine, as defined in
>      section 5.5 of [I-D.ietf-bfd-multipoint], for a session type
>      MultipointHead are only administratively driven, the state machine
>      for a session of type MultipointClient is same and the diagram is

"is the same"