[Gen-art] Genart last call review of draft-ietf-pim-reserved-bits-03

[Peter Yee via Datatracker <[e-mail]>]

Reviewer: Peter Yee
Review result: Ready with Issues

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Document: draft-ietf-pim-reserved-bits-03
Reviewer: Peter Yee
Review Date: 2019-09-03
IETF LC End Date: 2019-09-03
IESG Telechat date: Not scheduled for a telechat

Summary:  This document clarifies use of the PIM message header Reserved bits
and adds subtypes in order to extend the type space to allow for future usage. 
The expansion seems straightforward and reasonable.  [Ready with Issues.]

Major issues: None

Minor issues:

Page 6, Table 1: I'm not a fan of this table format.  It overloads the Name
column header to describe both the Type and the Flag Bits.  Perhaps something
that looks like (use a fixed-width font to view this properly):

    Type       Flag Bits   Name    Flag Bits Desc.        Reference
   ---------------------------------------------------------------------
     0                     Hello                       [RFC3973][RFC7761]
                 0-7               Reserved
...
    10                     DF Election                 [RFC5015]
                 0-3               Reserved
                 4-7               Subtype

It's a suggestion.  I just don't find the overloaded column header and repeated
data particularly appealing.  It took me a few seconds to figure out what was
being done here.  As it is, Name isn't a terribly good way of describing the
meaning of the Flag Bits.  Just a suggestion.

Nits/editorial comments:

General:

On all pages except the first, in the page header: change "Extention" to
"Extension".

Page 1, Abstract, 2nd and 3rd paragraphs: change all uses of RFCxxxx to RFC
xxxx.  The space-less form is only used for references within square brackets.

Specific:

Page 1, Abstract, 1st paragraph, 3rd sentence: change "per message" to
"per-message".

Page 3, Section 4, 1st paragraph, 3rd sentence: delete the comma.

Page 3, Section 4, 2nd paragraph, 1st sentence: append a comma after "Bits". 
Change "well defined" to "well-defined".

Page 4, Section 5, 1st sentence: change "pim" to "PIM".

Page 5, Figure 3 caption: You've used "sub-type", "SubType", "Subtype" (from
the revised IANA registry in Table 1) and here "Sub-Types".  I'd suggest
choosing one form and using it more consistently.  Given the spacing
requirements of the diagram, a hyphenated form would probably not be the
optimal choice.