UDP Communication

Compare the operations of transport layer protocols in supporting end-to-end communication.

UDP Low Overhead versus Reliability

• UDP does not establish a connection. UDP provides low overhead data transport because it has a small datagram header and no network management traffic.

UDP Datagram Reassembly

• UDP does not track sequence numbers the way TCP does.
• UDP has no way to reorder the datagrams into their transmission order.
• UDP simply reassembles the data in the order that it was received and forwards it to the application.

UDP Server Processes and Requests

• UDP-based server applications are assigned well-known or registered port numbers. UDP receives a datagram destined for one of these ports, it forwards the application data to the appropriate application based on its port number.

UDP Client Processes

• The UDP client process dynamically selects a port number from the range of port numbers and uses this as the source port for the conversation.
• The destination port is usually the well-known or registered port number assigned to the server process.
• After a client has selected the source and destination ports, the same pair of ports are used in the header of all datagrams in the transaction.

Other related topics

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