Do you think an intruder is on your computer using your network? Do you think you're being monitored? A simple automated way to find out is with Nirsoft's free CurrPorts app
CurrPorts is a network monitoring software that displays a list of all applications that have opened TCP/IP and UDP ports on your computer. However, the interesting features are described below. 
For each port included in the list, the application provides information about the process that opened the port, displays its name, gives the full path to where it is located, displays information about its version (product name, file description, and so on), the time it was created, and which user created it. This way, you can know where the attack came from.
Additionally, the application will allow you to close all unwanted TCP connections, and stop the process or processes that opened the ports. You can save all the information about TCP/UDP ports to an HTML, XML, or plain text file.
The application will automatically color in pink all suspicious TCP/UDP ports used by unknown applications, as it recognizes which ones do not have version information and an icon.
If you are interested in the application, you can download it for free from here.
More technical details about how the application works can be found on the official Nirsoft website.
