TCPView is a Windows program that will show you detailed listings of all TCP and UDP endpoints on your system, including the remote address and state of TCP connections. TCPView provides a conveniently presented subset of the Netstat program that ships with Windows NT.
When you start TCPView it will enumerate all active TCP and UDP endpoints, resolving all IP addresses to their domain name versions.
A toolbar button can be used to toggle the output to not resolving names, which in some cases can speed output since there is no querying of DNS servers for translations.
The Ctrl-R hotkey will toggle TCPView between resolving names and displaying raw IP addresses, and TCPView remembers the mode
it was in last when it is run again.