Re: [Suit] [Teep] Default, mandatory-to-implement algorithm

Michael Richardson <> Mon, 24 February 2020 18:30 UTC

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From: Michael Richardson <>
To: Russ Housley <>, Hannes Tschofenig <>, teep <>,
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Date: Mon, 24 Feb 2020 13:30:55 -0500
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Subject: Re: [Suit] [Teep] Default, mandatory-to-implement algorithm
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{should this be CC'ed to SUIT?}

Russ Housley <> wrote:
    > In the SUIT WG, I have been advocating HSS/LMS Hash-based signature as
    > the MTI algorithm.  This is a quantum resistant signature, and NIST has
    > already started the process to make it a FIPS-approved algorithm

That's great news!
Once we have paid the code space and figured out the network bandwidth to
accomodate it, does it even make sense to have another MTI?

I am concerned that the MTI, if not used periodically, might rot.
Or it might be surprising when we have to use it, that the cost is too high.

I am not clear if we need HSS/LMS for the general TEEP use.
It seems that the thing that need a quantum resistant secure upgrade is for
the TEE Agent code, not the TAx.  I'm not clear that the TEE Agent code
maintenance is even part of TEEP's mandate.

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