Re: [MLS] MLS in decentralised environments

Dave Cridland <dave@cridland.net> Tue, 03 April 2018 09:51 UTC

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From: Dave Cridland <dave@cridland.net>
Date: Tue, 3 Apr 2018 10:51:35 +0100
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To: Matthew Hodgson <matthew@matrix.org>
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Subject: Re: [MLS] MLS in decentralised environments
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On 3 April 2018 at 10:29, Matthew Hodgson <matthew@matrix.org> wrote:

> This feels like it could be quite a large oversight, given there are many
> real-time communication protocols and services (e.g. Matrix[1], Tox[2],
> Briar[3], Secure Scuttlebutt[4], Whisper[5], PSS[6], psyc2[7], XMPP
> FMUCs[8] (and MIX?), even NNTP and SMTP) where messages are replicated over
> a network of peers without any single controlling server


Just as a side-note, the only environment I know of using XMPP FMUC also
bans use of end-to-end encryption. MIX (XEP-0369) uses the same model of a
single definitive sequence of messages, currently. Neither MUC nor MIX
require a single server, however - just a single domain.

FMUC differs in simply having multiple "correct" sequences, where the
various sequence domains are split by having very lo links in between. This
is a trade-off in terms of UX, however - having a single sequence of
messages known to all participants (not just their clients) is useful, and
of absolutely critical importance in some environments.

Dave.