WinPcap "allows applications to capture and transmit network packets bypassing the protocol stack, and has additional useful features, including kernel-level packet filtering, a network statistics engine and support for remote packet capture."
Programs that use libpcap/WinPcap
Cain and Abel, a password recovery tool for Microsoft Windows. It can recover many kinds of passwords using methods such as network packet sniffing, cracking various password hashes by sing methods such as dictionary attacks, brute force and cryptanalysis attacks.
tcpdump, a tool for capturing and dumping packets for further analysis, and WinDump, the Windows port of tcpdump.
ngrep, aka "network grep", isolate strings in packets, show packet data in human-friendly output.
Wireshark (formerly Ethereal), a graphical packet-capture and protocol-analysis tool.
Snort, a network-intrusion-detection system.
Nmap, a port-scanning and fingerprinting network utility
the Bro IDS and network-monitoring platform.
URL Snooper, locate the URLs of audio and video files in order to allow recording them.
Kismet, for 802.11 wireless LANs
L0phtCrack, a password auditing and recovery application.
iftop, a tool for displaying bandwidth usage (like top for network traffic)
EtherApe, a graphical tool for monitoring network traffic and bandwidth usage in real time.
Bit-Twist, a libpcap-based Ethernet packet generator and editor for BSD, Linux, and Windows.
Pirni, a network security tool for jailbroken iOS devices.
McAfee ePolicy Orchestrator, Rogue System Detection feature
NetSim a network simulation software for network R & D
XLink Kai Software that allows various LAN console games to be played online
Firesheep, an extension for the Firefox web browser, that intercepts unencrypted cookies from certain websites (such as Facebook and Twitter) as the cookies are transmitted over networks, exploiting session hijacking vulnerabilities.
Suricata, a network intrusion prevention and analysis platform.
WhatPulse, a statistical (input, network, uptime) measuring application.
Xplico, a network forensics analysis tool (NFAT).
Scapy, a packet manipulation tool for computer networks, written in Python by Philippe Biondi.
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