Re: [Ace] EST over CoAP: Randomness

Michael Richardson <mcr+ietf@sandelman.ca> Wed, 15 May 2019 14:10 UTC

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From: Michael Richardson <mcr+ietf@sandelman.ca>
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Date: Wed, 15 May 2019 10:10:41 -0400
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Subject: Re: [Ace] EST over CoAP: Randomness
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My understanding of the use case for server generated keys is for existing,
deployed systems where the system can easily get a firmware update, but the
hardware TPM itself is unable/unwilling to generate new keys, and can't be
upgraded, but keys can be loaded.

Systems like Hannes' company produces, where the TPM is really a TEE don't
suffer from the upgrade problem, but there are many other systems out there
based upon older designs.

And, it's an optional part of the protocol; one I don't intend to support.
I don't see why it should bother anyone.

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