Nmap

nmap

nmap is very popular port scanning tool. It supports various scanning methods, allows scanning of ports through spoofed addresses and can also perform OS and service detection with great accuracy.

Converting MAC addresses to vendor names

When we try to do ping scan -sP with nmap for machines on LAN, it informs whether host is alive or not and also prints MAC address of the alive hosts. Along with MAC address vendor who manufactured the NIC is also shown. nmap uses '/usr/share/nmap/nmap-mac-prefixes' to convert MAC address (OUI part) to vendor name. The file is in plain-text format and other programs can also use it to convert MAC addresses to vendor names.