So to the first question, there&#x27;s not a transactional layer to guarantee the client handled the message. Once a message is sent to the client, it is assumed the client has a mechanism for queuing messages if it can&#x27;t keep up.<p>As to the second, the caveat is basically saying that if a message is broadcast and nobody cares about the message (ie: there aren&#x27;t any subscriptions) then mist isn&#x27;t going to store the message anywhere, it just gets dropped.