Re: [Endymail] [messaging] Mesh/Recrypt

Tony Arcieri <bascule@gmail.com> Tue, 23 August 2016 02:48 UTC

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From: Tony Arcieri <bascule@gmail.com>
Date: Mon, 22 Aug 2016 19:48:33 -0700
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To: Phillip Hallam-Baker <phill@hallambaker.com>
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Cc: messaging <messaging@moderncrypto.org>, endymail@ietf.org
Subject: Re: [Endymail] [messaging] Mesh/Recrypt
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On Mon, Aug 22, 2016 at 4:48 PM, Phillip Hallam-Baker <phill@hallambaker.com
> wrote:

> ​I suggested followups to the endymail@ietf.org mailing list rather than
> CFRG though.
>

Ok, CC'd! That said, here's a followup:

I was kind of confused why you cite RFC7748, but then go on to explain
things in terms of classical Diffie-Hellman.

As far as an ECC-based approach goes, I think something like the multiparty
Signal protocol[1] is a good starting point for how to solve the general
problem, and, as far as I can tell, addresses most of the concerns you
cited as a motivation.

The specific approach you detailed could be adapted to ECC as well.

[1] I'm not sure there's a more recent overview than this, which is
probably out-of-date: https://whispersystems.org/blog/private-groups/

-- 
Tony Arcieri