Google Public DNS - How Google Tries To Speed Up The Internet

Google has launched Google Public DNS as an alternative domain name service for any Internet user. Designed to replace the DNS services provided by ISPs or companies, Google says that its DNS will be faster and more secure than many other DNSs, and won't filter content.

An amazing similar alternative is OpenDNS but it appears most services on the Internet disappear slowly, as Google releases it's own, much better alternative to... everything.

The goals for Google's new DNS are:

• Speed: Resolver-side cache misses are one of the primary contributors to sluggish DNS responses. Clever caching techniques can help increase the speed of these responses. Google Public DNS implements prefetching: before the TTL on a record expires, we refresh the record continuously, asychronously and independently of user requests for a large number of popular domains. This allows Google Public DNS to serve many DNS requests in the round trip time it takes a packet to travel to our servers and back.
• Security: DNS is vulnerable to spoofing attacks that can poison the cache of a nameserver and can route all its users to a malicious website. Until new protocols like DNSSEC get widely adopted, resolvers need to take additional measures to keep their caches secure. Google Public DNS makes it more difficult for attackers to spoof valid responses by randomizing the case of query names and including additional data in its DNS messages.
• Validity: Google Public DNS complies with the DNS standards and gives the user the exact response his or her computer expects without performing any blocking, filtering, or redirection that may hamper a user's browsing experience.

Skeptics may say your local ISP may have faster DNS than Google, but:

"Google Public DNS is hosted in data centers worldwide, and uses anycast routing to send users to the geographically closest data center."

TechCrunch has it's own version for the reasons Google entered the DNS business:

In 2008 OpenDNS was making $20,000/day in revenue when they were resolving just 7 billion daily queries.

Here’s how money is made – when users enter a URL that can’t resolve, the service puts up its own landing page with search results and advertisements. And companies are very willing to pay for DNS services like these to stop employees from hitting malware sites (they are simply blocked), or other sites (porn, Facebook, etc.).

The new domain name servers (DNS) provided by Google are: 8.8.8.8 and 8.8.4.4. If you want to start using Google's DNS right away but don't know how to configure your computer domain name servers, see THIS page (it includes instructions for Windows, Linux and Mac OS X).

There are also a couple of screencasts you can follow for changing your DNS (Windows):

-Windows XP:



-Windows Vista / 7:



[videos via Labnol]

Additional info: The Official Google Blog and Google Code Blog.