Glossary · Automation fundamentals, platforms and components
Topology
Also known as: Network topology
German: Topologie
In automation and communication networks, topology is the arrangement of nodes and connections in a network or system, such as line, star, ring, tree or mesh. It determines cabling, redundancy options, fault behavior and performance.
- Automation components
In one sentence
Topology is the arrangement of nodes and connections, such as line, star, ring, tree or mesh, which shapes cabling, redundancy and fault behavior.
Example
The PROFINET network uses a ring topology with media redundancy, so one cable break does not stop communication with the drives.
How it applies
- Engineering: Fieldbuses such as RS-485 require line topology with termination; Ethernet-based networks use star, line and ring structures. Ring topologies with redundancy protocols tolerate a single break.
- Security: Network topology is the basis for zone and conduit design in OT security. Flat networks allow faults and attacks to spread.
- Documentation: An up-to-date topology diagram with device names, addresses and ports is essential for commissioning and troubleshooting. Update it with every change; outdated network drawings mislead service staff.
Physical vs. logical topology
Physical topology describes the cabling. Logical topology describes how data flows. A switched Ethernet network can be wired as a line through devices with integrated switches and still behave logically like a star.