[tcpm] Éric Vyncke's Discuss on draft-ietf-tcpm-converters-17: (with DISCUSS and COMMENT)

[Éric Vyncke via Datatracker <[e-mail]>]

Éric Vyncke has entered the following ballot position for
draft-ietf-tcpm-converters-17: Discuss

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DISCUSS:
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Thank you for the work put into this document. It is indeed useful to be able
to deploy easily new TCP features.

Nevertheless, please find below two DISCUSSes and some non-blocking COMMENTs
(and I would appreciate a response from the authors) and NITS.

I hope that this helps to improve the document,

Regards,

-éric

== DISCUSS ==

-- Section 1.2 --
A trivial one: while the title and the abstract of this document appear as
quite generic, the document focus is reduced later in section 1.2 to MPTCP:
  "this
   document specifies how the Convert Protocol applies for Multipath
   TCP.  It is out of scope of this document to provide a comprehensive
   list of all potential conversion services. "
While I do not mind having a focus on MPTCP only, I would strongly suggest to
reflect this focus in the title and in the abstract (the current filename is
correct).

-- Section 6.2.8 --
I appreciate that this is an experimental document, but, having only 2
occurrences of ICMP in the whole document and no real "how to process" TLV
"Destination Unreachable"... and the payload of this TLV having only the code
without the offending packet will probably make Path MTU discovery (and other
mechanisms) impossible.

While I am not a transport expert, I believe that this aspect needs to be
described in this document.


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COMMENT:
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Here are some COMMENTs
-- Section 1.2 --
Is the benefit of a transport proxy only for the clients as written in the 1st
paragraph? It was probably the case for the original MPTCP proxy but what about
other TCP extensions?

-- Section 4.1 --
While the difference "(Internet-facing interface, customer-facing interface)"
will probably represent the vast majority of use cases, I wonder whether there
will always be a single Internet-facing ? Could probably be 0 or 2 in some use
cases... Suggest to remove this part of the text.

-- Section 6.1 --
Please state the usual wording about "unassigned" field: it must be ignored by
the receiver.

Adding some explanations on why version 0 is reserved but cannot be used would
be welcome.

-- Section 6.2.5 --
Can the "remote peer IP address" be a link-local address ?

== NITS ==

-- Section 1.1 (and possibly others) --
Please use a consistent means of introducing acronyms, cfr URLLC and ATSSS ;-)

-- Section 4.2 ---
The use of "regular TCP packets" makes me wonder whether the authors think that
MPTCP uses "irregular TCP packets"... The use of 'regular' seems a little weird
here but I am not a native English speaker.

-- Section 4.3 --
The caption below figure 7 ends with "(TCP)" that is not the acronym of
"Transport Session Entry". Is it expected ?