Saturday, December 12, 2009

Google Public DNS - Is it worth it?

On December 3rd Google announced their newest service, and potentially the most troubling, privacy wise. Google Public DNS is supposed to be optimized to provide a better DNS service than your ISP can. You might wonder how Google could do that, and why we should - or should not - use Google DNS.

First, it helps to understand what DNS is. DNS stands for Doman Name Service, and is the reason we are able to remember to type http://www.walmart.com instead of having to remember http://161.170.244.20/.  Sites on the internet are actually mapped by IP number. Since groups of 12 numbers can be hard to remember, the Domain Name Service, aka DNS was devised. DNS takes the easy to remember www.walmart.com and connects it to the real IP address of 161.170.244.20. The web wouldn't work nearly as well without DNS. With it, if I don't know a companies web address, I can make a few guesses and probably figure it out. If I had to guess an actual IP address, I'd probably die before I got it right.

The reason this is a privacy issue is that while Google knows an incredible amount about us already because of our searches, they only know what we search for and what we links we click in the results. If you make Google Public DNS your DNS provider, they know everything you do on the web. Every site you go to, every file you download, every streaming video you watch. It will all pass through Google. Google claims they are not going to share that information except in aggregate - meaning statistical groupings, ie males between the ages of 18 and 25 are more likely to go to gamespot.com than females between the ages of 40 and 50. Given the ad earning potential of such information, I'm not surprised Google is getting into the DNS business. With a world wide presence Google would be instant king of the information world. Well, Google is already king so I guess the next step up would be promotion to emperor.

I know that Googles stated reason to run DNS servers is to improve everyones internet experience, but does that really hold water? If you select the Google as your DNS provider you have to go through your ISP's servers before you can reach Googles, plus however many hops there are between you ISP and Google servers. Plus your speed getting to Google servers will be affected by the condition, settings and traffic on all of the servers between you and Google. I doubt you'll see much improvement over your ISP's servers. Of course, since the differences will be measured in a few milliseconds, even if Googles DNS is faster, I doubt you'll be able to tell. Is that worth turning every single bit of data your web surfing generates over to Google? I don't think so.