If you remember the old remote networking software "NetBus" it's like that. When you enter a range of IP's to send the advertisement to, it sends whats called a "Windows Message" to the IP address. Which results in a windows box popping up on the screen on millions of peoples desktops, with your advertisment in it. IP advertising does not however, support graphics or HTML. Simply I windows box pops up with your message and an "Ok" button. When the user clicks "Ok" they are brought to your website.