What is EtherNet/IP?
A leading industrial protocol in the US, EtherNet/IP is a big player in the factory and process manufacturing landscapes. It is one of the four networks, all managed by ODVA (Open DeviceNet Vendors Association), that adapt CIP to an industrial network (DeviceNet, ControlNet, CompoNet). EtherNet/IP is an application layer protocol that is transferred inside a TCP/IP Packet. EtherNet/IP is the way that data is organised within the packet.
Those born before the turn of the century will be very familiar with the term ‘ethernet’, the word will likely conjure the image of a cable that connects your modem to your computer. In that instance the cable is a vessel for ethernet messages to be transmitted. Within said vessel, you’ll find a host of communications protocols such as the “Internet Protocol”, the “Transport Control Protocol” (TCP) and various Microsoft protocols. When used collectively, this selection of protocols provides the perfect structure for the office environment. It will allow internet use, sending of messages, sharing of files and access to devices like printers.
In an industrial setting however, requirements vary greatly from the office. The data being transmitted in a factory, for example, comes from programmable logic controllers (PLCs) which access operator workstation and input/output devices. Digital communications in industrial settings must be real-time – if they aren’t serious problems can occur.
For industrial IoT as a whole, EtherNet is fully accepted for industrial automation. The advent of intelligent switches and routers is owed to this wide acceptance of EtherNet. These days there are simple ways to connect slave devices to Allen Bradley PLCs or integrate those PLCs into building automation systems.
When is EtherNet/IP used?
EtherNet/IP tends to be used in industrial settings in order to connect to assets and devices such as PLCs, robots, sensors, CNCs and additional industrial machines. It’s a very complex and robust protocol that is based on the common industrial protocol (CIP).
The reason for EtherNet/IP being used in the industrial setting frequently is due to its real-time and high-integrity capabilities. It uses TCP/IP for routing data for which the integrity is crucial and uses other protocols such as UDP/IP for data that must been transmitted quickly. A process line is a perfect example of this. Without real-time data transmission with high integrity, process lines could fall victim to oversights and faults which can massively impact energy use, efficiency, and maximum yield output.
All devices on an EtherNet/IP network present their data to the network as a series of data values called attributes grouped with other similar data values into sets of attributes called ‘objects.’
Network device objects
Similar to other communications protocols such as BACnet, EtherNet/IP is able to discover devices as a series of objects. These objects are a list of property data directly associated with the device. This could be anything from energy data to temperature or moisture data. EtherNet/IP is able to access and deliver this information to other devices.
Heaps of vendors are EtherNet/IP compatible including the likes of Schneider Electric, ABB, IFM, Kepware and many more. You can see a full list of compatible vendors here.