Re: [Rats] Composite Evidence

Michael Richardson <> Fri, 24 January 2020 18:21 UTC

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From: Michael Richardson <>
To: "Eric Voit \(evoit\)" <>
cc: "Smith\, Ned" <>, "rats\" <>
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Date: Fri, 24 Jan 2020 13:21:27 -0500
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Subject: Re: [Rats] Composite Evidence
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Eric Voit (evoit) <> wrote:
    >> If it makes sense to define "routing claims" that assert that A2 intended to
    >> piggy back AR1 with E2 then that should imply that if E2 = (c1) and c2 =
    >> routing claim then E2' = (c1, c2). The conveyance still carries (AR1, E2') , but
    >> possibly the c2 claim names AR1 as the piggy i.e. = "AR1".
    >> V2 can verify the c2 claim and create an AR2' claim"AR1" and send
    >> (AR1, AR2'); where AR2 = (c4,...,cn) and AR2' = (c3, c4,...,cn). RP can similarly
    >> verify c3. Namely, the"AR1" claim is inspected to have payload AR1
    >> as piggy.
    >> The "routing" claims are ancillary to the basic roles and messages that are
    >> the core basis for trust among the endpoint entities -  IMO. The core flows
    >> are separable from routing. Routing shouldn't lead us down a path of having
    >> new types of evidence (E3).

    eric> I agree that routing itself doesn't imply a new type of evidence.
    eric> What we do have at Attester is some trigger for when to collect the
    eric> specific set of claims which are needed by the Relying Party to
    eric> accomplish a particular use case.

I think that it's important.
In my automobile/tire situation, it is important that the attestation result
that my car sends are for tires attached to *my* car.  Even if they were on
your car this morning when they were evaluated.

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