Subject: Lars Eggert's No Objection on draft-ietf-6man-mtu-option-13: (with COMMENT)

From: Lars Eggert via Datatracker <[email-masked]>
Date: Tue, 05 Apr 2022 07:42:23 -0700

Lars Eggert has entered the following ballot position for
draft-ietf-6man-mtu-option-13: No Objection

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COMMENT:
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Section 5. , paragraph 9, comment:
>      Min-PMTU: n 16-bits.  The minimum MTU recorded along the path
>                  in octets, reflecting the smallest link MTU that
>                  the packet experienced along the path.
>                  A value less than the IPv6 minimum link
>                  MTU [RFC8200] MUST be ignored.

Would there be any value in using a scheme that can encode MTUs larger than
64K? Could steal some bits by not defining a way to encode values below 1280.

Thanks to Paul Kyzivat for their General Area Review Team (Gen-ART) review
(https://mailarchive.ietf.org/arch/msg/gen-art/cSJ1VnpREVnAknRj_ANN0QFRdA0).

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NIT
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All comments below are about very minor potential issues that you may choose to
address in some way - or ignore - as you see fit. Some were flagged by
automated tools (via https://github.com/larseggert/ietf-reviewtool), so there
will likely be some false positives. There is no need to let me know what you
did with these suggestions.

Section 2. , paragraph 3, nit:
-    This results in many transport connections being configured to use
+    This results in many transport-layer connections being configured to use
+                                  ++++++

Section 2. , paragraph 4, nit:
-    size available for a transport to use.  Also, some use-cases increase
+    size available for a transport protocol to use.  Also, some use-cases increase
+                                  +++++++++

Section 6.3. , paragraph 3, nit:
-    This avoids the transport needing to retransmit a lost packet that
+    This avoids the transport protocol needing to retransmit a lost packet that
+                             +++++++++

Section 6.3.1. , paragraph 10, nit:
-    *  A datagram transport can utilise DPLPMTUD [RFC8899].  For example,
-                                     ^
+    *  A datagram transport can utilize DPLPMTUD [RFC8899].  For example,
+                                     ^

Section 6.3.4. , paragraph 4, nit:
-    *  The actual PMTU may be lower than the Rtn-PMTU value because the
-                                                                   ----

Reference [RFC2460] to RFC2460, which was obsoleted by RFC8200 (this may be on
purpose).

Reference [RFC1063] to RFC1063, which was obsoleted by RFC1191 (this may be on
purpose).

Section 4. , paragraph 3, nit:
> IANA-HBH]. Length: 4 The size of the each value field in Option Data field su
>                                  ^^^^^^^^
Two determiners in a row. Choose either "the" or "each".

Section 6.2. , paragraph 2, nit:
> acket with this option in response to a R-flag, as well as which packets to i
>                                       ^
Use "an" instead of "a" if the following word starts with a vowel sound, e.g.
"an article", "an hour".

Section 8.4. , paragraph 4, nit:
>  mitigate the impact by responding to a R-Flag by including the option in a p
>                                       ^
Use "an" instead of "a" if the following word starts with a vowel sound, e.g.
"an article", "an hour".

---

From: Bob Hinden <[email-masked]>
Date: Tue, 5 Apr 2022 08:42:10 -0700

See below, marked GF+BH :

> On Apr 5, 2022, at 7:42 AM, Lars Eggert via Datatracker <[email-masked]> wrote:
> 

GF+BH: We designed this option to support packet lengths that can be carried in the IPv6 header.   No consideration was given to go beyond that.

> (https://mailarchive.ietf.org/arch/msg/gen-art/cSJ1VnpREVnAknRj_ANN0QFRdA0).

GF+BH: We will look at these in the next revision of the draft.