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CurrPorts is network monitoring software that displays the list of all currently opened TCP/IP and UDP ports on your local computer. For each port in the list, information about the process that opened the port is also displayed, including the process name, full path of the process, version information of the process (product name, file description, and so on), the time that the process was created, and the user that created it.

Advanced Port Scanner is a fast and free port scanner allowing you to quickly find open ports (TCP and UDP) on network computers and retrieve versions of programs running on the detected ports. The program provides easy access to network resources such as shared folders, HTTP, HTTPS, FTP, RDP and Radmin. You can wake or shut down computers remotely. There is also an option to run quick commands (ping, tracert, telnet and SSH) on a selected PC.

Free Port Scanner is a small, fast, easy-to-use and robust port scanner for the Win32 platform.You can scan ports on fast machines in a few seconds and can perform scan on predefined port ranges. This tool uses TCP packets to determine available hosts and open ports, service associated with port and other important characteristics. The tool is designed with a user-friendly interface and is easy to use.

Netactview is a graphical network connections viewer for Linux, similar in functionality with Netstat. It includes features like process information, host name retrieval, automatic refresh and sorting.