Re: [Cfrg] When TLS is an overkill...

Peter Gutmann <pgut001@cs.auckland.ac.nz> Tue, 26 February 2019 03:54 UTC

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From: Peter Gutmann <pgut001@cs.auckland.ac.nz>
To: "Dr. Pala" <director@openca.org>, "cfrg@irtf.org" <cfrg@irtf.org>
Thread-Topic: [Cfrg] When TLS is an overkill...
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Date: Tue, 26 Feb 2019 03:54:32 +0000
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References: <307807bf-09eb-96c7-028f-df9573463b11@openca.org> <1551140056245.65505@cs.auckland.ac.nz>, <d53dd35f-dcb0-a562-d432-955dc30155b3@openca.org>
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Subject: Re: [Cfrg] When TLS is an overkill...
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Dr. Pala <director@openca.org> writes:

>provide a building block that developers and engineers can use to secure 
>the communication between two peers by using a low number of messages.

It still leaves way too much unstated... what's a low number?  Is there a
limit on bandwidth or message size?  Does one side need to be authenticated,
or both, or neither?  Is there a constraint on CPU use?  Is auth via a
third party (e.g. a CA) or mutual?  Do you need algorithm agility?  etc.

Coming up with something as a gedanken experiment is always fun, but
without a concrete goal or goals to act as success criteria you can never 
know whether you've achieved what you were aiming for.

Peter.