Re: [Rats] I-D: draft-rundgren-cote-00

Anders Rundgren <> Thu, 21 July 2022 16:29 UTC

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Date: Thu, 21 Jul 2022 18:29:24 +0200
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From: Anders Rundgren <>
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Subject: Re: [Rats] I-D: draft-rundgren-cote-00
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On 2022-07-21 15:38, Michael Richardson wrote:
> Anders Rundgren <> wrote:
>      > In this case my assumption is that the overarching goal is providing an
>      > object typing mechanism permitting a common receiver dispatching the
>      > handling of received objects to different processors depending on their
>      > type.
> I think that in 90% of the situations, the processor expects a very limited
> number of types, often only one.

I don't doubt that.

>      > In RATS it appears that you are currently dealing with not less than
>      > three different typing systems (media types, CBOR tags, profile URLs)
>      > which (in my simple mind...) feels slightly over the top.
> media-types, encoded by Content-Formats over CoAP apply to data in transit.
> CBOR tags (whether via file-magic, or just alone) go with the data at rest.

This is the thing I don't fully understand the point with and even less how these two methods relate to each other.

Although I have very limited insights in CoAP systems, I wouldn't be too surprised if it turns out that many servers actually ignore content types.

Note that this is independent of which object-integral type-scheme is used.  That's another discussion :)


> I'm not sure where I'd situate profile URLs.
> It just seems like lazy coding by people used to online software where you'd
> better have the latest code, or you are screwed.
> To me, they only make sense if there is active code at the URL that can make
> sense of the content.
> While I can imagine such a thing for something detailed, complex and never
> standardized, it's hard for me to make up a reasonable example.
> (Maybe there is a sufficiently rich declarative data description rather than
> active code, but then that data description is itself a well known content)
> If as you said in another thread, the software to intrepret the complex data
> is already locally installed, then it must also be sufficiently well defined
> that a trip through IANA isn't a problem.
> --
> ]               Never tell me the odds!                 | ipv6 mesh networks [
> ]   Michael Richardson, Sandelman Software Works        | network architect  [
> ]        |   ruby on rails    [
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