[General] TokTok group chat key agreement: How is Done (if is done)?

[pcmagas]

Whilst I was reading the TokTok protocol specification as part of my
master thesis, I was wondering how actually group chat is handled, I
mean most applications either agree on a common key via gropup key
agreement protocols or via sending keys directly on top of pairwize
encrypted channels.

As fas as I understood for the TokTok protocol in 2-party communications
an Eliptic curve group chat protocol is done in order to create a
XSalsa20 symmetric key, but on the group chats how is done, what keys
are used in order for the participants to communicate to each other?


Your sincerelly,

Dimitrios Desyllas