KNX

SMA lists KNX as a communication protocol, alongside EEBus, SEMP and Modbus. SMA defines a protocol as a standardized method for transmitting data. A communication standard is different: it is the physical transmission medium. So KNX works at the data-exchange level, not the physical level. Wi-Fi, ZigBee and radio are the communication standards that carry the data.

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• sentence 3: support check: partial - The passage implies KNX is a protocol and Wi-Fi, ZigBee and radio are standards (physical medium), but doesn't explicitly say KNX works at the data-exchange level or that those standards carry the data. -->