[mpls] Genart last call review of draft-ietf-mpls-rfc8287-len-clarification-02

[Ines Robles via Datatracker <[e-mail]>]

Reviewer: Ines Robles
Review result: Ready with Issues

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Document: draft-ietf-mpls-rfc8287-len-clarification-02
Reviewer: Ines Robles
Review Date: 2019-07-30
IETF LC End Date: 2019-07-31
IESG Telechat date: Not scheduled for a telechat

Summary:

I believe the draft is technically good. This document is well written.

The document updates RFC8287 by clarifying the length for the following Segment
ID Sub-TLVs: IPv4 IGP-Prefix Segment ID Sub-TLV, IPv6 IGP-Prefix Segment ID
Sub-TLV and IGP-Adjacency Segment ID Sub-TLV.

There are some minor issues detailed below that should be addressed.

Major issues: Not found

Minor issues:

1- Section 3 - Requirements notation is not complete, it should be added:  "NOT
RECOMMENDED" and "...are to be interpreted as described in BCP 14 [RFC2119]
[RFC8174] when, and only when, they appear in all capitals, as shown here."

2- Figure of Section 4.2: Type = 35 (IPv4 IGP-Prefix SID) ---> Type = 35 (IPv6
IGP-Prefix SID)

2.1- It would be nice if the figures have a caption where we can point to the
figure number, and the figure number is referenced in the text. The same for
the table of Section 4.3.

3- Question: What do you think?

I think it would be nice to explain a bit more the length for the different
combinations of the table of Section 4.3, e.g. with tables as detailed below:

+-----------------------------+-------------------+
|            Field                               | Parallel (octets) |
|     rfc8287#section-5.3            +-----+------+------+
|                                                       | Any | OSPF | ISIS |
+-----------------------------+-----+------+------+
|      Local Interface ID                    |  4  |   4  |   4  |
+-----------------------------+-----+------+------+
|     Remote Interface ID                 |  4  |   4  |   4  |
+-----------------------------+-----+------+------+
| Advertising Node Identifier          |  4  |   4  |   6  |
+-----------------------------+-----+------+------+
|  Receiving Node Identifier             |  4  |   4  |   6  |
+-----------------------------+-----+------+------+
|           Reserved                                 |  2  |   2  |   2  |
+-----------------------------+-----+------+------+
|     Adj. Type + Protocol                     |  2  |   2  |   2  |
+-----------------------------+-----+------+------+
|       Sum Total octets =                      |  20 |  20  |  24  |
+-----------------------------+-----+------+------+

+-----------------------------+-------------------+
|            Field                                |   IPv4 (octets)   |
|     rfc8287#section-5.3             +-----+------+------+
|                                                        | Any | OSPF | ISIS |
+-----------------------------+-----+------+------+
|      Local Interface ID                     |  4  |   4  |   4  |
+-----------------------------+-----+------+------+
|     Remote Interface ID                 |  4  |   4  |   4  |
+-----------------------------+-----+------+------+
| Advertising Node Identifier           |  4  |   4  |   6  |
+-----------------------------+-----+------+------+
|  Receiving Node Identifier             |  4  |   4  |   6  |
+-----------------------------+-----+------+------+
|           Reserved                                  |  2  |   2  |   2  |
+-----------------------------+-----+------+------+
|     Adj. Type + Protocol                     |  2  |   2  |   2  |
+-----------------------------+-----+------+------+
|       Sum Total octets =                     |  20 |  20  |  24  |
+-----------------------------+-----+------+------+

+-----------------------------+-------------------+
|            Field                                |   IPv6 (octets)          |
|     rfc8287#section-5.3           +-----+------+------+
|                                                       | Any | OSPF | ISIS |
+-----------------------------+-----+------+------+
|      Local Interface ID                    |  16 |  16  |  16  |
+-----------------------------+-----+------+------+
|     Remote Interface ID                  |  16 |  16  |  16  |
+-----------------------------+-----+------+------+
| Advertising Node IdentifieR           |  4  |   4  |   6  |
+-----------------------------+-----+------+------+
|  Receiving Node Identifier              |  4  |   4  |   6  |
+-----------------------------+-----+------+------+
|           Reserved                                  |  2  |   2  |   2  |
+-----------------------------+-----+------+------+
|     Adj. Type + Protocol                     |  2  |   2  |   2  |
+-----------------------------+-----+------+------+
|     sum  Total octets =                       |  44 |  44  |  48  |
+-----------------------------+-----+------+------+

Nits/editorial comments: Issue tool: Summary: 0 errors (**), 0 flaws (~~), 0
warnings (==), 1 comment (--).

Thanks for this document,

Ines