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

Derek Atkins <derek@ihtfp.com> Fri, 21 December 2018 18:06 UTC

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From: Derek Atkins <derek@ihtfp.com>
To: Martin Pagel <Martin.Pagel=40microsoft.com@dmarc.ietf.org>
Cc: David Brown <david.brown@linaro.org>, Michael Richardson <mcr+ietf@sandelman.ca>, "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 13:05:35 -0500
In-Reply-To: <DM5PR21MB06984CC3CF3075F362FB410A9DBF0@DM5PR21MB0698.namprd21.prod.outlook.com> (Martin Pagel's message of "Thu, 20 Dec 2018 02:05:14 +0000")
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Subject: Re: [Suit] self-describing format vs fixed/binary manifest structure - pull parser
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Martin Pagel <Martin.Pagel=40microsoft.com@dmarc.ietf.org> writes:

> 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.

-derek
-- 
       Derek Atkins                 617-623-3745
       derek@ihtfp.com             www.ihtfp.com
       Computer and Internet Security Consultant

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