Re: [Suit] SUIT Architecture document review

Michael Richardson <mcr+ietf@sandelman.ca> Wed, 16 October 2019 15:47 UTC

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From: Michael Richardson <mcr+ietf@sandelman.ca>
To: Henk Birkholz <henk.birkholz@sit.fraunhofer.de>
cc: Hannes Tschofenig <Hannes.Tschofenig@arm.com>, Kathleen Moriarty <kathleen.moriarty.ietf@gmail.com>, "suit\@ietf.org" <suit@ietf.org>
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Comments: In-reply-to Henk Birkholz <henk.birkholz@sit.fraunhofer.de> message dated "Wed, 16 Oct 2019 16:41:04 +0200."
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Date: Wed, 16 Oct 2019 17:48:24 +0200
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Subject: Re: [Suit] SUIT Architecture document review
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Henk Birkholz <henk.birkholz@sit.fraunhofer.de> wrote:
    > That said, in theory the SUIT manifest could be used to update basically
    > things of any size - not only constrained nodes. But I agree with your point
    > that this is just a "title" problem. There are solutions, such as package
    > systems,  in place that would require a quite more complex and elaborate
    > attestation infrastructure and that is not the scope SUIT is targeting, I
    > think.

An Android IoT device is effectively an RPI running Android code.
Yes, it has a Linux kernel and file system, and yes, it can load "apps", but
in practice, one would always want to replace the entire system as a unit.

A Mozilla IoT device is also an RPI running Raspbian, with nodejs running
the application code.  It has apt for packaging, etc. and that's useful
during development, but shipping that would be dumb.  Ship a signed file
system image.

Just remember that RPIs are as big and powerful as the laptop you had ten
years ago.

    > m2c: wrt to number of secrets and endorsements that would have to be
    > maintained per device we also want to be as minimalist as we can be while
    > remaining feasible, I think.

--
Michael Richardson <mcr+IETF@sandelman.ca>ca>, Sandelman Software Works
 -= IPv6 IoT consulting =-