How does one decide between TCP and UDP? This question was originally answered on Quora by Keith Winstein.

The PortQry.exe utility is a convenient tool to check the response of TCP/UDP ports on hosts to diagnose issues related to the operation of various network services and firewalls in TCP/IP networks.

Using the –b, -o, -an, interval, and tasklist commands, you can find IP addresses, port numbers, connections, process IDs and associated DLLs that are using the TCP and UDP ports.

Test if Firewall is blocking a Port. Check which Ports are being used. Also learn how to check which process or service is using the open port.

Scott Reeves shares the wireshark filters that helps you isolate TCP and UDP traffic.

<p>As with any network and internet-capable computing system, many of Apple's services and programs require access to the internet and/or local network using TCP and UDP ports to function properly ...

This paper seeks to reflect a comparative analysis between the two transport layer protocols, which are TCP/IP and UDP/IP, as well to observe the effect of using these two protocols in a client ...

According to this group, starting with February 1, 2020, DNS servers that can't handle DNS queries over both UDP and TCP may be pushed out of the DNS ecosystem and stop working.