The 3 Tiered Architecture
Why a 3-Tiered vs. a 2-Tiered Architecture?
Problems such as server bottlenecks, network bottlenecks, software distribution, multi-platform support and security holes present in the traditional client-server architecture are overcome and solved with a 3-tiered client-server architecture by introducing a layer between the client application and the database server called the application server layer (shown in diagram below).


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