Functional Principle
With EtherCAT, the Ethernet packet or frame is no longer received, and then interpreted and copied as process data at every node. Instead, the EtherCAT slave devices read the data addressed to them while the telegram passes through the device. Similarly, input data is inserted while the telegram passes through. The frames are only delayed by a fraction of a microsecond in each node, and many nodes - typically the entire network - can be addressed with just one frame.