IP Calculator / IP Subnetting
ipcalc takes an IP address and netmask and calculates the resulting
Network Calculators
Free TCP/IP Network Calculators. Includes web-based Subnet, Supernet and network / node calculators.
Wireshark [download]
Wireshark is a network protocol analyzer for Unix and Windows. List of features.
EtherApe [download]
Featuring link layer, IP, and TCP modes, EtherApe displays network activity graphically with a color coded protocols display. Hosts and links change in size with traffic.
Ngrep [download]
ngrep (network grep) is a network packet analyzer. It runs under the command line, and relies upon the pcap library and the GNU regex library.
Cain and Abel [download]
Cain & Abel is a password recovery tool for Microsoft Operating Systems.
NetworkMiner [download]
NetworkMiner is a Network Forensic Analysis Tool for Windows.
TCPDump [download]
tcpdump is a common packet analyzer that runs under the command line.
Kismet [download]
Kismet is a console (ncurses) based 802.11 layer-2 wireless network detector, sniffer, and intrusion detection system.
Ettercap [download]
Ettercap is a suite for man in the middle attacks on LAN. It features sniffing of live connections, content filtering on the fly and many other interesting tricks.
P0f [download]
P0f is able to identify the operating system of a target host simply by examining captured packets even when the device in question is behind an overzealous packet firewall.
inSSIDer [download]
inSSIDer is a wireless network scanner for Windows, OS X, and Android.
NetStumbler [download]
Netstumbler is the best known Windows tool for finding open wireless access points (“wardriving”).
dSniff [download]
Dsniff is a set of password sniffing and network traffic analysis tools to parse different application protocols and extract relevant information. dsniff, filesnarf, mailsnarf, msgsnarf, urlsnarf, and webspy passively monitor a network for interesting data (passwords, e-mail, files, etc.).
KisMAC [download]
KisMAC is a wireless network discovery tool for Mac OS X. It has a wide range of features, similar to those of Kismet
Ntop [download] limited to 2,000 packets capture
Ntop shows network usage in a way similar to what top does for processes. In interactive mode, it displays the network status on the user’s terminal.
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