The behaviour of Master and Slave is exactly the same as in the previous scenario, i.e. a Slave always responds to the address from which the request was sent. If by chance two simultaneous requests from different Masters are received by a slave radiomodem, the RipEX radio modem waits for the first reply from the connected SCADA device before transmitting the request which arrived second. The 500 ms timeout applies again, i.e. when there is no reply for the first request, the second one is transmitted after the timeout expires.