Google's latest free service domain name resolution

Stuart Corner
Friday, 04 December 2009 02:45

Your IT - Home IT

Google has launched yet another free service for the world's Internet community that it claims is superior to current offerings: domain name resolution.

Whenever you try to access a web site or send an email, servers within the Internet translate the URL, such as www.itwire.com into an IP address, a string of numbers. Normally this service is provided by your ISP via its domain name servers (DNS) and your computer holds the IP address of those servers so that they are queried whenever you try and access a web site.

Google is offering to provide this service for every Internet user, and claims to be able to do it better. To make use of the Google alternative all you need to do is put the IP addresses of the Google Public DNS servers into your PC (instructions below).

Google claims to have implemented a number of techniques to enable its domain name servers to deliver web pages faster than others. According to a posting on Google's official blog "Complex pages require multiple DNS lookups before they start loading. This can slow down the browsing experience. Our research has shown that speed matters to Internet users, so over the past several months our engineers have been working to make improvements to our public DNS resolver to make users' web-surfing experiences faster, safer and more reliable...As people begin to use Google Public DNS, we plan to share what we learn with the broader web community and other DNS providers, to improve the browsing experience for Internet users globally. The goal of Google Public DNS is to benefit users worldwide while also helping the tens of thousands of DNS resolvers improve their services, ultimately making the web faster for everyone."

 One technique described is to constantly update the IP address of many frequently requested domains in its own servers.
The DNS structure is hierarchical and the DNS queried by a user refers to others higher up the hierarchy to obtain an IP address. However once obtained it will retain that address for a period of time, the so called time to live (TTL) that can be set and can vary from seconds to weeks.

CONTINUED