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

"FOSSATI, Thomas (Thomas)" <> Wed, 30 September 2015 21:28 UTC

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From: "FOSSATI, Thomas (Thomas)" <>
To: Spencer Dawkins <>, The IESG <>
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"
< on behalf of>
>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
> 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 which is what we imply

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