I've come across on the internet some domains getting prefix of ww2 or ww3 approximately (ww2.somedomain.com, ww3.yourdomain.com). Which happen mostly when travelling from the page to page. What will be the reason of getting such subdomains? Can there be anything special about the subject or could they be yet another sub domain? I am talking about, could they be helpful in a particular context?

Only agreed to be curious to understand. Thanks.

People running large(-ant) sites i did so this when they have to split up the burden between several server. One machine could be known as world wide web then the next could be known as www2, etc.

Today, far better load balancing solutions can be found that do not need you to expose your internal machine naming conventions towards the browser clients.

Technically, the initials prior to the primary domain title (e.g. the "mail" in mail.yahoo.com) could be best regarded like a machine title, determining the net server/mail server, whatever. They are able to also identify several machines (an internet farm).

Therefore the person accumulating that machine can refer to it as anything they need. The initials world wide web really are a (somewhat arbitrary) convention.

Oftentimes, ww can be used to point a specific server of some shown servers. If correctly set up, I possibly could have world wide web.mydomain.com indicate my site on the load balancer, as i can use ww1, ww2, ww3, etc to gain access to the website guaranteed from the specific LBed server.

I can tell 3 options

  • result in the browser load assets more faster. the browser would open a set quantity of link with same domain to not load the server
  • they're using more the other server to allow them to share the burden between servers
  • separate some content to some separate virtual host or server. some type of organization ...

Typically it is a partitioning strategy. When sites get sufficiently large they can't run (or run well) on one server after this you have to check out solutions for scaling the applying out flat (ie more servers) instead of up and down (ie bigger servers).

Some example partitioning methods are:

  1. Certain customers always employ certain servers. This is often arbitrary or according to some criteria (user type, geographic location, etc)
  2. Whenever a user will get a session that session is designated to particular server (sometimes known as "sticky periods" even though this may also be used where such different machines are transparent) and
  3. Certain activities will always be on certain machines.

nothing special, they are utilized if you want them....