Using an Ethernet LAN to interconnect sensors, instruments, machine tools, medical monitors, restaurant appliances, POS terminals and other devices. In the mid-1990s, Comtrol Corporation created the first "device server," which converts serial transmission to Ethernet, enabling serial-based devices to communicate over a LAN instead of dedicated cabling. Although newer devices have Ethernet ports, legacy devices have serial ports. In the industrial world, some machine tools have lifespans of 20 years or more. In device networking architectures, devices may or may not interact with each other. Although many do, device networking is also used to remotely monitor independent machines just to ensure that they are up and running. See multiport serial card and industrial control network.