This paper presents a computer tool to support in the project and development of an industrial Ethernet network, verifying the physical layer (cables–resistance and capacitance, scan time, network power supply–POE’s concept ”Power Over Ethernet” and wireless), and occupation rate (amount of information transmitted to the network versus the controller network scan time). These functions are accomplished without a single physical element installed in the network, using only simulation. The computer tool has a software that presents a detailed vision of the network to the user, besides showing some possible problems in the network, and having an extremely friendly environment.