WinPcap

WinPcap is an open source app consisting of a driver and a library, which taken together, make it an indispensible tool for using a large number of commercial networking tools, among other things. WinPcap has become the go to application for the sector, becoming just as integral a part of open source applications as it is for commercial ones. WinPcap's main function is to capture network packets, but it can also filter the captured packets and generate statistical data for an internal network. If you are looking for a tool to monitor and safeguard your network or software to protect your system or network from possible threats, your first port of call should be this all encompassing library that provides the engine to power many of the best applications in the sector.