News And Releases

WinPcap, though still available for download (v4.1.3), has not seen an upgrade in many years and there are no road map/future plans to update the technology. While community support may persist, technical oversight by Riverbed staff, responses to questions posed by Riverbed resources, and bug reporting are no longer available.

Gordon Lyon, Nmap project founder, has created Npcap, a packet capture library for Windows, that includes WinPcap compatibility and may be a suitable replacement for WinPcap and WinPcap Pro. Information can be found at



Introduction to WinPcap

For many years, WinPcap has been recognized as the industry-standard tool for link-layer network access in Windows environments, allowing applications to capture and transmit network packets bypassing the protocol stack, and including kernel-level packet filtering, a network statistics engine and support for remote packet capture.

WinPcap consists of a driver that extends the operating system to provide low-level network access and a library that is used to easily access low-level network layers. This library also contains the Windows version of the well-known libpcap Unix API.

Thanks to its set of features, WinPcap has been the packet capture and filtering engine for many open source and commercial network tools, including protocol analyzers, network monitors, network intrusion detection systems, sniffers, traffic generators and network testers. Some of these networking tools, like Wireshark, Nmap, Snort, and ntop are known and used throughout the networking community. is also the home of WinDump, the Windows version of the popular tcpdump tool. WinDump can be used to watch, diagnose and save to disk network traffic according to various complex rules.