[pim] Robert Wilton's No Objection on draft-ietf-pim-null-register-packing-15: (with COMMENT)

[Robert Wilton via Datatracker <[e-mail]>]

Robert Wilton has entered the following ballot position for
draft-ietf-pim-null-register-packing-15: No Objection

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COMMENT:
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Updated.  Discuss cleared - thanks for addressing my discuss issue.

Regards,
Rob

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Previous comments:

Minor level comments:

(2) p 2, sec 2.  Packed Null-Register Packing Capability

   0                   1                   2                   3
   0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  |PIM Ver| Type  |P|6 5 4 3 2 1 0|           Checksum            |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  |             Group Address (Encoded-Group format)              |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  |            Source Address (Encoded-Unicast format)            |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      Figure 1: PIM Register-Stop message with Packing Capability option

I found the description of the flag bits to be unclear:
 - Are the "6 5 .. 1 0", the flag bits?
 - Is 'P' the "Packed Capability" bit?  If so, this diagram implies that it
 takes the value 7, but the text indicates that it hasn't been permanently
 assigned yet.

(3) p 3, sec 3.  PIM Packed Null-Register message format

      0                   1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |PIM Ver| Type  |Subtype|  FB   |           Checksum            |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |     Group Address[1]   (Encoded-Group format)                 |
      |     Source Address[1]  (Encoded-Unicast format)               |
      .                                                               .
      .                                                               .
      .                                                               .
      .                                                               .
      .     Group Address[N]                                          .
      |     Source Address[N]                                         |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
              Figure 2: PIM Packed Null-Register message format

Unclear what FB means, "Flag Bits"?  Also in section 4.

Nit level comments:

(4) p 4, sec 5.  Protocol operation

                                                             However, it
      is RECOMMENDED to stick to the packed format as long as the RP and
      DR have the feature enabled.

As an editorial nit, I would suggest combining these two sentences together to
make it clear what "the decision" is referring to.  The same comment also
applies to the pragraph below.

Regards,
Rob