I want to build a web application/server with this structure:

• main-server
  • sub-server
    • transaction-server (create, update, delete)
    • view-server (view, search)
• authentication-server
• documents-server
• reporting-server
• library-server
• e-learning-server

The main-server acts as host server for sub-server.

I can add many sub-servers and connect it to main-server (via plug-play interface maybe), then it can begin querying data from another sub-servers (which has been connected to the main-server). The sub-servers can be anywhere as long as connected to internet.

The main-server can manage all sub-servers which are connected to it (query data, setting permission between sub-servers, etc).

The purpose is simple, the web application will be huge as the company grows, so I want to distribute it into small connected plug-able servers.

My question is, does the structure above already have a standardized method? or are there any different views? what are the technologies needed?

I need a lot of researches before the execution plan begin.

thanks a lot.