How are UDP segments transported across the network?

UDP segments are transported across the network by being encapsulated within IP packets. This encapsulation process involves taking the UDP segment, which contains the header and data of the message meant for the application layer, and placing it inside an IP packet. The IP layer is responsible for addressing and routing the packet to its destination.

UDP, or User Datagram Protocol, is a connectionless protocol, meaning it does not establish a continuous connection between sender and receiver before transmitting data, nor does it guarantee the delivery of segments, which is different from protocols that require a connection, like TCP. This is why options that imply a continuous connection are not applicable for UDP.

Furthermore, UDP segments are not transmitted individually as frames at the data link layer. Instead, they encapsulate into packets, which are then framed according to the data link protocol in use (like Ethernet). The statement regarding conversion into application messages pertains to the function of the application layer rather than the transport mechanism of UDP itself.

In summary, the correct understanding of UDP transport is that it relies on encapsulation within IP packets to move across the network, allowing for efficient and fast transmission of data without establishing a connection.