Part 15 of the Industrial Networking: Serial to Ethernet training series
TCP and UDP belong in the transport layer of the Seven Layer model. In TCP, when a device sends out a message the other device sends a message back, while in UDP the message is sent out with no response. Anything sent to a port that an application is not listening to is discarded.
Long-time automation trainer Doug Bell, Interconnecting Automation, covers the basics of Industrial Networking with AutomationDirect’s Chris Harris. This video is produced by CFE Media to be noncommercial and educational. Runtime is approximately 6 minutes.