The customer needed to communicate important substation information using DNP3. All of the substations that needed to communicate over TCP/IP with the central SCADA system were already equipped with Siemens S7-300 PLCs and attached Ethernet modules that were being used to gather the information from the power substation. DMC used hardware already in place to provide functionality for all of the layers of the robust DNP3 protocol, and went to a train substation to verify and debug the system. 

The software DMC created used two separate Ethernet connections to communicate with the central server, thus helping prevent loss of data. Additionally the implementation had a large data buffer, so that even if both connections were down data would be sent after a connection was reestablished. Using the DMC software the server is able to send trip/close commands to relays, control analog setpoints, read digital outputs, and read analog values from any of the power substations in the network. This provided a stable communication system for the railroad's SCADA system.

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