Glossary · Distributed automation and IEC 61499
Segment model
Also known as: Network segment (IEC 61499), Segment
German: Segmentmodell
In IEC 61499 system configurations, a segment represents a communication network segment, such as an Ethernet network, to which devices are linked; it describes how the devices of a distributed system are connected for exchanging events and data.
- IEC 61499
- Standards
In one sentence
In IEC 61499 system configurations, a segment represents a communication network segment that links devices for event and data exchange.
Example
The system configuration shows three controllers and an edge device linked to one Ethernet segment, over which the distributed application communicates.
How it applies
- Engineering: In the system configuration, segments and links show which devices can communicate. Tools use this information, together with device addresses, when generating communication for connections that cross device boundaries.
- Network design: The segment in the model is a simplified view. The real network design, with switches, VLANs and routing, must be documented separately and match the model.
- Security: Network segments are the basis for security zoning. Communication between segments that belong to different Security zone areas passes through a Conduit with defined protection.
- Documentation: Keep the system configuration diagram and the network documentation consistent: device names, addresses and segment names should match.
Segment model vs. network topology
The IEC 61499 segment is a modeling element for engineering tools. The network topology describes the physical and logical network in full detail. Both are needed; neither replaces the other.