Forwarding Frame
Posted: 22 Mar 2024, 12:51
How does a device know that the incoming PROFINET frame should be forwarded? Is it MAC address based?
Each Ethernet frame contains an address field that is used in Layer 2 (switching or bridging) to transmit the frames in a directed manner (point to point = unicast or point to multipoint = multicast/broadcast). This means that in the case of a unicast frame, only the network lines between sender and receiver see the frame where the frame is to be transmitted. All other nodes see nothing of the frame.Webinar_Question wrote: ↑22 Mar 2024, 12:51 How does a device know that the incoming PROFINET frame should be forwarded? Is it MAC address based?
The address field in layer 2 contains the destination and the sender, both on a MAC address basis. The switches/bridges learn these MAC addresses and save them in the Forwarding Database (FDB).