[trill] Alvaro Retana's No Objection on draft-ietf-trill-p2mp-bfd-08: (with COMMENT)

[Alvaro Retana <[e-mail]>]

Alvaro Retana has entered the following ballot position for
draft-ietf-trill-p2mp-bfd-08: No Objection

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COMMENT:
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(1) The first reference to I-D.ietf-bfd-multipoint appears in Section 5; please
add one in the Introduction when Multipoint BFD is initially mentioned.

(2) I think that using Normative Language (without quotation marks) to mention
what is specified somewhere else can result in confusion as to which is the
authoritative document.  This seems to be the case in Section 4: "If the M bit
of the TRILL Header of the RBridge channel packet containing a BFD Control
packet is non-zero, the packet MUST be dropped [RFC7175]."  The sentence sounds
as if the behavior is specified in rfc7175, but that document says (in Section
3.2 (BFD Control Frame Processing)): "The following tests SHOULD be
performed...Is the M bit in the TRILL Header non-zero?  If so, discard the
frame."  Note that the behavior specified in rfc7175 doesn't use a "MUST".  The
text in this document seems to be used to explain why a new message is needed,
and not in a Normative way -- please clarify the text so that there is no
inconsistency with respect to rfc7175.

(3) Section 5 says that the "processing in Section 3.2 of [RFC7175]
applies...If the M bit is zero, the packet is discarded."  Section 3.2 has that
"SHOULD" that I mentioned above, and it also mentions potential security
issues, which are not referenced in this document.  Are there reasons to keep
the "SHOULD" and not use "MUST" instead (for the p2mp case)?  If the same
semantics as in rfc7175 are kept, then the Security Considerations should
include the concerns.