The chat service uses the standard protocol Jabber/XMPP. See also Chat.

Administration web Interface
The Jaber server comes with a web administrative interface for members of the jabberadmins group.
Federation (S2S)
XMPP allows for servers communicating seamlessly with each other, forming a global ‘federated’ IM network.
File transfer maximum speed
Limit in Byte/second the maximum file transfer.
File transfer normal speed
Limit in Byte/second the normal file transfer.