Unix-like systems implement pcap in the libpcap library; for Windows, there is a port of libpcap named WinPcap that is no longer supported or developed, and a port named Npcap for Windows 7 and later that is still supported.
[6] The MIME type for the file format created and read by libpcap, WinPcap, and Npcap is application/vnd.tcpdump.pcap.
[9] While libpcap was originally developed for Unix-like operating systems, a successful port for Windows was made, called WinPcap.
It has been unmaintained since 2013,[10] and several competing forks have been released with new features and support for newer versions of Windows.
WinPcap consists of:[11] Programmers at the Politecnico di Torino wrote the original code.
It also forces some limitations such as being unable to capture 802.1Q VLAN tags in Ethernet headers.
[14] It is based on WinPcap, but written to make use of Windows networking improvements in NDIS version 6.