Google maintains over 450,000 servers, arranged in racks located in clusters in cities around the world

When an attempt to connect to Google is made, DNS servers resolve www.google.com to multiple IP addresses, which acts as a first level of load balancing by directing clients to different Google clusters. When you send Google a domain name the server resolves to multiple IP addresses, typical implementation of clients is to use the first IP address for communication. The order of IP addresses provided by DNS servers for a domain name is typically done using Round Robin policy on Google's internet servers. Each Google server cluster has thousands of servers, and upon connection to a cluster further load balancing is performed by hardware in the internet server cluster, in order to send the queries to the least loaded web server.

This makes Google one of the biggest and most complex known content delivery networks.


Types of Internet servers

This is going to be series of post on the types of internet servers. Some very cool stuff

Cheers