Re: [Dtls-iot] Spencer Dawkins' Yes on draft-ietf-dice-profile-16: (with COMMENT)

"FOSSATI, Thomas (Thomas)" <thomas.fossati@alcatel-lucent.com> Wed, 30 September 2015 21:28 UTC

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From: "FOSSATI, Thomas (Thomas)" <thomas.fossati@alcatel-lucent.com>
To: Spencer Dawkins <spencerdawkins.ietf@gmail.com>, The IESG <iesg@ietf.org>
Thread-Topic: [Dtls-iot] Spencer Dawkins' Yes on draft-ietf-dice-profile-16: (with COMMENT)
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Date: Wed, 30 Sep 2015 21:28:14 +0000
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Subject: Re: [Dtls-iot] Spencer Dawkins' Yes on draft-ietf-dice-profile-16: (with COMMENT)
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Hi Spencer,

Thanks for your comments.  Quick reply on this one:

On 30/09/2015 19:04, "dtls-iot on behalf of Spencer Dawkins"
<dtls-iot-bounces@ietf.org on behalf of spencerdawkins.ietf@gmail.com>
wrote:
>
>In this text,
>
>   On the other hand, the way DTLS handles
>   retransmission, which is per-flight instead of per-segment, tends to
>   interact poorly with low bandwidth networks.
>   
>I'm assuming you are using "per-flight" in the
>https://tools.ietf.org/html/rfc5681 sense of the term ("FLIGHT SIZE: The
>amount of data that has been sent but not yet cumulatively
>acknowledged"), but that's somewhat obscure, especially outside of TSV,
>and there's no definition or reference for it in this document. Perhaps
>you could say something like
>
>   On the other hand, DTLS handles loss by retransmitting the
>   entire amount of data that has been sent but has not been
>   cumulatively acknowledged, and this tends to
>   interact poorly with low bandwidth networks.

The term "flight" has a precise connotation in DTSL (see
https://tools.ietf.org/html/rfc6347#section-4.2.4) which is what we imply
here.

In the paragraph just above the one you've quoted, we reference section
4.2.4 of RFC 6347 which is where the term is originally introduced; so,
although implicitly, we provide the context.

I agree this is not perfect, but it's not easy to guess what the reader
knows already, what his/her mental filters are, etc, so I'm not sure what
we could do to make the text better/unambiguous?

Cheers, t