The IAB file contains all of the IABs (Individual Address Blocks) that have been registered with IEEE. Each IAB entry in the file specifies the first 36-bits of the 48-bit Ethernet hardware address, leaving the remaining 12-bits for use by the registering organisation. For example the IAB entry "0050C2003", registered to Microsoft, applies to any Ethernet hardware address from 00:50:c2:00:30:00 to 00:50:c2:00:3f:ff inclusive. Each IAB assignment represents a total of 2^12 (4,096) Ethernet addresses.
Major Ethernet hardware vendors typically use an OUI registration rather than an IAB registration. See get-oui(1) for details.
This script can be used to update the arp-scan IAB file from the latest data on the IEEE website. It is relatively rare to see Ethernet addresses from IAB registrations, so the IAB file is not as important as the OUI file.
The IAB data is fetched from the URL http://standards.ieee.org/regauth/oui/iab.txt and the output file is saved to the file ieee-iab.txt in the current directory. The URL to fetch the data from can be changed with the -u option, and the output file name can be changed with the -f option.
The ieee-iab.txt file that is produced by this script is used by arp-scan to determine the Ethernet card vendor from its hardware address.
The directory that arp-scan will look for the ieee-iab.txt file depends on the options used when it was built. If it was built using the default options, then it will look in /usr/local/share/arp-scan.
$ get-iab -v Renaming ieee-iab.txt to ieee-iab.txt.bak Fetching IAB data from http://standards.ieee.org/regauth/oui/iab.txt Fetched 230786 bytes Opening output file ieee-iab.txt 1535 IAB entries written to file ieee-iab.txt
get-iab uses the LWP::UserAgent Perl module to fetch the data from the IEEE website. You must have this module installed on your system for it to work. This module is available on most distributions, often called libwww-perl. It is also available in source form from CPAN.
You can use a proxy server by defining the http_proxy environment variable.
http://www.nta-monitor.com/wiki/ The arp-scan wiki page.