Functionality
UDP and TCP are widely used in network communication. UDP is a connectionless transport protocol. It has a similar task as the connection oriented TCP. This means that the sender does not know whether the data packets it has sent have arrived. While TCP sends acknowledgements when receiving data, UDP does without. This has the advantage that the packet header is much smaller, and the transmission link does not have to transmit acknowledgements.
Typically, UDP is used for DNS requests, VPN connections, audio and video streaming.
UDP is not configured in the hardware tree. UDP is implemented applicatively via a library.
There are two libraries, one that works on the lowest level (SysSocket2, library, to get access to the socket interface for TCP/IP communication on the target.) and a user library (Net Base Services, this library implements a TCP server, TCP client and a UDP peer as a collection
of base services for Ethernet).
⮫ “Library Manager functionality”
⮫ “Overview of protocols, sockets and ports”
⮫ “Reference, function blocks”
The ⮫ application example demonstrates the communication between an AC500 V2 PLC and an AC500 V3 PLC via UDP protocol.