TCPView - TCPView is a Windows program that will show you detailed listings of all TCP and UDP endpoints on...
CurrPorts - CurrPorts displays the list of all currently opened TCP/IP and UDP ports on your local computer.
Proc Net Monitor - SecurityXploded is an Infosec Research Organization offering 200+ FREE Security/Password Recovery Tools, latest Research Articles and FREE Training on Reversing/Malware Analysis
TcpView For Linux - TcpView For Linux. Touch screen friendly design graphical network connections viewer for Linux.
Total Network Monitor - Total Network Monitor is a network monitoring software that is designed to continuously monitor your local network, individual computers, and services. Free for 60 days.
NetStat Agent - At whatever point you open a site association through your program or download documents, you are opening TCP/UDP connions.