DNS (Domain Name System) is an essential part for the proper working of Internet and speedy access to surf the web. DNS resolves and translates domain names (e.g. www.mydigitallife.info) which is meaningful to humans into the IP address in numerical (binary) identifiers associated with networked server or host so that requests routed though the Internet can locate the address of the devices worldwide.

By connecting to Internet through ISP (Internet Service Provider), and getting an local IP address with DHCP automatically getting the settings, most system has silently used the DNS servers of the ISP without user noticing. People who feels that DNS service from ISP is not up to par, slow, unreliable or fail to resolve many web address now has one more free public DNS service to choose from, in addition to OpenDNS.

Google Public DNS is a public DNS resolver from Google that is launched as an effort to make the web browsing faster, according to official Google Blog.

According to launch announcement, features of Goolge Public DNS include:

  1. 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.
  2. 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.
  3. 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.

The best about Google Public DNS is extremely easy to remember IP addresses:

8.8.8.8
8.8.4.4

To use Goolge Public DNS as the default DNS servers, just configure system or router/gateway network settings to use the IP addresses 8.8.8.8 and 8.8.4.4 as the DNS servers.

How to Configure and Use Google Public DNS

Google provide comprehensive configuration instructions to change DNS settings in Windows, Mac OS X, Linux, and routers equipment or mobile devices.