Multilayered architecture

There is also an architectural pattern that is named Layers and has been described in different publications, including the book Pattern-Oriented Software Architecture A System of Patterns.

The concepts of layer and tier are often used interchangeably. However, one fairly common point of view is that there is indeed a difference, and that a layer is a logical structuring mechanism for the elements that make up your software solution, while a tier is a physical structuring mechanism for the system infrastructure.

Notes