Re: [Ace] EST over CoAP

Michael Richardson <> Mon, 14 May 2018 14:46 UTC

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From: Michael Richardson <>
To: Hannes Tschofenig <>
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Date: Mon, 14 May 2018 10:45:45 -0400
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Subject: Re: [Ace] EST over CoAP
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Hannes Tschofenig <> wrote:
    > Thanks for the feedback.

    > Why do you think it takes so long to get this document finished? In the
    > end, you are just carrying EST over CoAP instead of conveying it over
    > HTTP.

It's not really just us, it's time to get people to do the reviews required :-)
It's also constrained about getting other documents out.  RFC8366 spent 4
weeks in AUTH48 due to a small YANG correction discovered at the last minute.
(And we had to bikeshed the title)

    > PS: Regarding the use of DTLS/TLS for the proxy. There are obviously
    > ways to get this accomplished but the question for me is whether this
    > functionality should go into this version of the spec or rather a
    > companion document.

I don't understand the use case.
EST requires a secure transport from requesting entity to Registrar.
A DTLS/TLS proxy represents a MITM, and I don't see a way for either party to
trust it.    I have been pushing to better detail how people want this to work.

Michael Richardson <>, Sandelman Software Works
 -= IPv6 IoT consulting =-