You must noticed www1 or www2 once in a while when you are visiting a website. WWW1, WWW2 or even WWW3 is nothing but a mirror of the original web server which is typical WWW. Many websites like government, banks even major search engines like Google(www1.google.com or www2.google.com) and Yahoo(www1.yahoo.com or www2.yahoo.com)! uses www1 and www2. The main purpose of this techniques is to reduce server load. Sometimes the original server need to be updated or modified but major websites like .gov, .edu, google.com, yahoo.com cannot just shut their main server down for hours to update their system. Therefore, they need to use www1 or www2 duplication of their mainframe server.
Sometimes this different servers used for the serving users based on their geographical location. Suppose, if someone typehttp://www.google.com form US, they might be taken to the original google server which means http://www.google.com but if someone type http://www.google.com from Africa, it might take them to www2.google.com or www1.google.com.
I was surprised that not a lot of information showed up in Google or Yahoo when i was searching for it. If you know more about WWW2 or WWW1 please feel free to share with everyone here by adding your comment at the bottom. I was wondering if there is any security issue behind this mirror web server policy?