The RPC object is used to make remote calls to other connected peers in a networked game.
The functions available in this class are determined by the messages object that you set up in the .network_config data file that you use to initialize the Network. In order to send a message of a particular type, you call an equivalent function on the RPC object. The message is sent to the remote peer. Then, when the Network.update() function is called on the remote peer, a function with the same name is transparently invoked on the callback handler object passed to Network.update().
For example, the .network_config file could set up a message type called hello_world as follows:
messages = { hello_world = {} }
In this case, you could send that message to a peer by calling the hello_world() function of the RPC object:
stingray.RPC.hello_world(peer_ID)
When the remote peer calls:
stingray.Network.update(delta_time, my_callback_object)
the engine will automatically call my_callback_object:hello_world().
For complete details, see the networking documentation.