The Messaging Layer Security (MLS) Protocol
I find the most interesting discussions surrounding this protocol are about whether or not it should support deniability &#x2F; repudiation of messages. The Off-The-Record messaging people--including specifically Ian Goldberg--were unhappy that this was a non-goal, and the reasoning on the mailing list at the time was frustrating (that deniability can be used by &quot;terrorists&quot; to dodge investigations); but, I have also seen them have better arguments on their issue tracker (about power imbalances... though this argument was also controversial).<p><a href="https:&#x2F;&#x2F;mailarchive.ietf.org&#x2F;arch&#x2F;msg&#x2F;mls&#x2F;ZJ4e78obXSdYWnxmsNUqGc_qe68&#x2F;" rel="nofollow">https:&#x2F;&#x2F;mailarchive.ietf.org&#x2F;arch&#x2F;msg&#x2F;mls&#x2F;ZJ4e78obXSdYWnxmsN...</a><p><a href="https:&#x2F;&#x2F;github.com&#x2F;mlswg&#x2F;mls-architecture&#x2F;issues&#x2F;50" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;mlswg&#x2F;mls-architecture&#x2F;issues&#x2F;50</a>