this creates a table of macaddress, whose prefix(vendor id) is specified, to md5

create_macaddress2md5_table.rb

#!/usr/bin/env ruby
# -*- encoding: utf-8 -*-
require 'digest/md5'

prefix =
  begin
    ARGV[0].downcase
  rescue
    '90840d'
  end

def to_hex(i)
  sprintf('%02x%02x%02x', i / 2**16, i / 2**8 % 2**8, i % 2**8)
end

(0...2**24).each { |i|
  mac = prefix + to_hex(i)

  print mac, "\t",Digest::MD5.new.update(mac),"\n"
}