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Three-Tier

Webopedia Staff
Last Updated May 24, 2021 7:57 am
A special type of client/server architecture consisting of three well-defined and separate processes, each running on a different platform:

1. The user interface, which runs on the user’s computer (the client).

2. The functional modules that actually process data. This middle tier runs on a server and is often called the application server.

3. A database management system (DBMS) that stores the data required by the middle tier. This tier runs on a second server called the database server.

The three-tier design has many advantages over traditional two-tier or single-tier designs, the chief ones being:

  • The added modularity makes it easier to modify or replace one tier without affecting the other tiers.
  • Separating the application functions from the database functions makes it easier to implement load balancing.