From OpenSCADAWiki
OpenSCADA also supports the initiation of such connections itself, that is, it can act as a data source for "gray" and dynamic IP. So, the input transport of the module "Sockets" and the module "SSL" in the mode 2 initiates the connection and then sends an identifying sequence and enters the normal mode of receiving requests from the host to which it is connected. 
Regarding what is currently especially useful is the remote control of OpenSCADA stations in "gray" networks with such a connection.