EtherNet/IP networks must use segmentation, but there are some topology options that allow a designer to customize the network and ensure maximum operability.

The base topology is called star topology. In this setup, all of the lines extend from the central control to each individual device. In this case, there is one line for every device. What happens if a line is cut, though? The device is incapacitated.

To fix this, there are a number of other solutions that can be implemented on sets of devices. The first is the ring topology. In a ring topology, multiple devices are wired sequentially, one after another, until they form a ring. If a cable is cut within the ring, each device still has a path to control.

Spanning Tree Topology, or STP for Spanning Tree Protocol, is similar, but slightly more redundant. In STP, sets of devices or switches are wired with connections between each of them forming a web. Rather than send messages randomly and wait for them to go through, though, the switches use an algorithm to determine the most efficient path. The direct path is the first choice, but if that is cut, the algorithm can determine the next best solution until it finds a path that is not cut.

Finally, one solution is not a topology as much as a unique way to connect two devices. Link aggregation is the process of connecting two devices with two or more cables. This is beneficial in high-volume networks. When all cables are connected, the connection can use all of them to create high-speed, high-volume through fare. If a cable is cut, there is still a connection, but it operates proportionally slower.

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