PROFINET is the innovative open standard for Industrial Ethernet, developed by Siemens and the Profibus User Organization (PNO).
There are essentially two types of PROFINET: Real-Time (RT) and Isochronous Real-Time (IRT). Since PROFINET is an open standard, this means manufacturers can develop their own PROFINET products, like PLCs, Drives, IOs, and diagnostic tools.
PROFINET defines cyclic and acyclic communication between components, including diagnostics, functional safety, alarms, and additional information. To link all of those components, PROFINET employs standard Ethernet to connect all the devices within a network. This allows other Ethernet protocols to coexist within the same infrastructure (OPC UA, MQTT, SNMP etc).
PROFINET is a full duplex system. PROFINET networks are often designed as a star topology, or as several stars branching off a large ring backbone by using managed PROFINET switches.
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