Glossary · Industrial communication
Network topology
Also known as: Topology
German: Netzwerktopologie
In communication networks, the network topology is the arrangement of nodes and the links between them, such as bus, line, star, ring, tree or mesh. The physical topology describes the cabling; the logical topology describes how data flow.
- Industrial communication
In one sentence
Network topology is the arrangement of nodes and links, such as bus, line, star, ring or mesh, physically and logically.
Example
The machine uses a line topology to the drives, a star topology in the control cabinet and a ring between cabinets for redundancy.
How it applies
- Engineering: Topology decides cable effort, failure behavior and timing. Lines follow the machine layout, stars simplify diagnostics, rings with redundancy protocols tolerate a single link failure.
- Commissioning: The actual topology is compared with the planned one. Many engineering tools can read the topology via LLDP and compare it automatically.
- Maintenance: Knowing the topology tells maintenance staff which devices lose communication when a cable or device is removed.
- Documentation: The documentation team provides topology drawings showing devices, ports and cable types, and keeps them up to date after changes. In the operating instructions, the effect of interrupting a link is more useful to readers than the topology name.
Physical vs. logical topology
A star of cables around a switch can carry a logical bus, and a physical ring can run as a logical line while one port is blocked by Media Redundancy Protocol (MRP). Drawings should say which view they show.