IP Port Spy

IP Port Spy is a small-sized and portable application that listens to a port to show information on certain frames. It comes packed with limited settings that should be figured out in no time.
As installation is not a requirement, you can drop the executable file somewhere on the hard disk and click it to run.
It is also possible to save IP Port Spy to a USB flash disk or similar storage unit, in order to run it on any workstation without prior installers.
What's important to take into account is that the Windows registry does not get updated with new entries, and files are not left behind on the hard disk after removing the tool.
The program is wrapped in a plain and simple interface with a minimal layout. You can start listening to a port by specifying its number and type (TCP or UDP). Note that it must not be currently in use. Aside from TCP connections, no responses will be sent to the far end.
Displayed data can be copied to the Clipboard via the right-click or Edit menu. There are no other notable options available through this tool.
IP Port Spy does not put a strain on computer performance or interrupt normal user activity, since it runs on a very low quantity of CPU and RAM, and it can be minimized to the taskbar. No error dialogs were shown in our tests, and the app did not hang or crash. We have not encountered any issues.
Unfortunately, IP Port Spy has not been updated for a pretty long time, and it may not run properly on newer operating systems. Otherwise, the tool delivers a straightforward solution when it comes to listening to ports.