For the purposes of demonstrating differences between TCP and UDP, I'm piping the contents of a file across a network connection, and recording the interaction with Wireshark. Everything looks normal in TCP, but in UDP things get a little weird.
I'm setting up listening on Machine A with
netcat -ul 5000
Then sending the file from Machine B with:
netcat -u <ip address> 5000 < file.txt
When I review the Wireshark log, I get half the message through UDP packets, and half apparently through IPv4 with no datagram at all (see screenshot below).
Is this just Wireshark being weird in the way it displays data, or is half the message really coming across without anything from UDP? And why?