network security tools

Nmap – port scanner http://nmap.org/

Nessus – Vulnerability detector http://www.tenable.com/products/nessus

Air-Crack – Wireless Cracker http://www.aircrack-ng.org/

Ettercap – port sniffer http://ettercap.github.com/ettercap/

Iptraf – Network Monitor http://iptraf.seul.org/

Medusa – Login brute-forcer http://www.foofus.net/~jmk/medusa/medusa.html

Snort – Intrucion Detection http://www.snort.org/

W3af – Web Application Attack http://w3af.org/

NetCat – networking utility http://netcat.sourceforge.net/

THC-Hydra – network logon cracker http://thc.org/thc-hydra/

Wapiti – Web application vulnerability scanner http://wapiti.sourceforge.net/