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Re: [Suit] self-describing format vs fixed/binary manifest structure - pull parser

Michael Richardson <mcr+ietf@sandelman.ca> Fri, 21 December 2018 18:25 UTC

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From: Michael Richardson <mcr+ietf@sandelman.ca>
To: Derek Atkins <derek@ihtfp.com>
cc: Martin Pagel <Martin.Pagel=40microsoft.com@dmarc.ietf.org>, David Brown <david.brown@linaro.org>, "suit@ietf.org" <suit@ietf.org>, "dev-mcuboot@lists.runtime.co" <dev-mcuboot@lists.runtime.co>
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Date: Fri, 21 Dec 2018 13:25:47 -0500
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Subject: Re: [Suit] self-describing format vs fixed/binary manifest structure - pull parser
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Derek Atkins <derek@ihtfp.com> wrote:
    >> Thanks, David, Yes, I am familiar with pull parsers, thanks to
    >> Brendan's example, but I'm not sure what the advantage of CBOR
    >> encoding provides if you build a custom parser for a particular fixed
    >> CBOR encoding/schema. Seems

    > The benefit is that you can create standardized server software that
    > can read the manifest to any particular MCU client without requiring
    > special per-MCU software.

    > The cost to the MCU to process a CBOR-pull is relatively low.  But the
    > cost to a server to deal with dozens (or more!) of uniquely-defined MCU
    > static manifest structures would be extremely high.

Since I think it's unlikely to happen, there would be a many servers, with
the result that at least one or more systems would not have a server
available, and would never get upgraded.

That's an incredibly high cost: if that results in a compromised
network/building/airport/etc.

-- 
]               Never tell me the odds!                 | ipv6 mesh networks [
]   Michael Richardson, Sandelman Software Works        |    IoT architect   [
]     mcr@sandelman.ca  http://www.sandelman.ca/        |   ruby on rails    [

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