Heavy duty machines have become more electronically sophisticated and in-vehicle electronics are growing in number and complexity, keeping pace with technology advancements. New machines implements (both mounted or trailed) and machine automation, demand this evolution, and thus a new way of designing on-board Electronic Control Units (hereafter ECU) is required. Moreover, the connectivity between vehicles, often extended to World Wide Web, and machine control and Working Session Task Controllers demand to become really distributed and executed in real time. So, integrated control systems ask for more performing distributed controls over networks, in order to better manage the machine torque and power and in order to optimize the fuel consumption, as a function of power request. In a similar way, more complex distributed control systems ask for using all machine actuators and sensors from remote Electronic Control Units (ECUs) “by wire”, using a networked control system efficient, fast and safe. The paper realizes a first practical experience of the SAE J 1939 protocol migration from the CAN network to the more performing and world accepted TCP/IP protocol over Ethernet, due the new industrial and automotive trends related to special versions of the general purpose network real time and safety oriented.