Re: [MLS] I-D Action: draft-ietf-mls-protocol-06.txt

Richard Barnes <> Thu, 30 May 2019 15:48 UTC

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From: Richard Barnes <>
Date: Thu, 30 May 2019 11:48:35 -0400
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To: Messaging Layer Security WG <>
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Subject: Re: [MLS] I-D Action: draft-ietf-mls-protocol-06.txt
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Hi all,

As discussed at the interim, the authors have produced a version that has a
bunch of typo and bugfixes on -05.  This should be a good target for
implementation and analysis.  We plan to focus draft-07 (in the IETF 105
time frame) on more performance-related changes that have less impact on
the analysis.

One particular note / call for ideas: The interaction between the common
framing and the confirmation MAC has led to a rather awkward dance to keep
the transcript hash up to date.  If folks have ideas for how we could more
elegantyl provide the authentication function that the confirmation MAC
provides, they would be very welcome.  Mr. Beurdouche made some suggestive
comments at the interim, but has yet to make a concrete proposal, so the
field is open :)


On Thu, May 30, 2019 at 11:45 AM <> wrote:

> A New Internet-Draft is available from the on-line Internet-Drafts
> directories.
> This draft is a work item of the Messaging Layer Security WG of the IETF.
>         Title           : The Messaging Layer Security (MLS) Protocol
>         Authors         : Richard Barnes
>                           Jon Millican
>                           Emad Omara
>                           Katriel Cohn-Gordon
>                           Raphael Robert
>         Filename        : draft-ietf-mls-protocol-06.txt
>         Pages           : 52
>         Date            : 2019-05-30
> Abstract:
>    Messaging applications are increasingly making use of end-to-end
>    security mechanisms to ensure that messages are only accessible to
>    the communicating endpoints, and not to any servers involved in
>    delivering messages.  Establishing keys to provide such protections
>    is challenging for group chat settings, in which more than two
>    clients need to agree on a key but may not be online at the same
>    time.  In this document, we specify a key establishment protocol that
>    provides efficient asynchronous group key establishment with forward
>    secrecy and post-compromise security for groups in size ranging from
>    two to thousands.
> The IETF datatracker status page for this draft is:
> There are also htmlized versions available at:
> A diff from the previous version is available at:
> Please note that it may take a couple of minutes from the time of
> submission
> until the htmlized version and diff are available at
> Internet-Drafts are also available by anonymous FTP at:
> _______________________________________________
> MLS mailing list