Depending on how close you are to your local nerd, you should have already heard about a computer virus that, it is claimed, will cause thousands of people to lose their internet access in just a few days on July 9th. Some folks don't even know it's coming, some have waved it off as a hoax, and some have even gone so far as to claim immunity because, of course, nothing could penetrate their primitive anti-virus shields, regardless of everything I've been trying to tell them. At any rate, it's happening.
So what exactly's going on? The culprit behind this scheduled havoc is a particular class of malware known as DNS Changer. Before I get into what exactly it's doing, I should give you a short primer on DNS and what it does - because after all, like it's named, DNS Changer changes DNS.
"Phone Numbers for the Web" - A Quick DNS Primer
Think about phone numbers for a second. Suppose my phone number is (123) 456-7890. If someone has that phone number written down, and just that phone number, they have no idea who exactly they're calling if they punch it into a phone. The information they have to contact me over the phone is incomplete. Now if they have two pieces of information - the phone number and my name to go with it, then that makes far more sense. Now they know that I'm at the other end of (123) 456-7890.
DNS is exactly the same thing. Internet websites have what's called an IP address (think phone number for a website). Now let's make an example. I'm going to give you an IP address, and you tell me what that address goes to. Ready? OK, here it is: 220.127.116.11. Complete gibberish to you? I'll tell you what. Take that number and put it into your web browser where you put in what website you want to go to, and tell me if it doesn't take you right to Google. DNS is what allows your browser to cleanly translate domain names to IP addresses - in this case it matches up 18.104.22.168 to "http://www.google.com." Just like a phone number. You don't get out your cell every time you want to call me and dial out (123) 456-7890. You go to my name. Your address book, as it turns out, is a mini list of DNS entries, matching numbers to names.