My professor said, that adding multiple layers in the BLL, will make the 3-tier an n-tier architecture.
But from my understanding (I may be wrong), a tier is a physical separation, and a layer is a logical seperation, so adding multiple layers will still keep it a 3-tier application, wouldn't it?
Best Answer
You are absolutely correct when you say
1- Horizontal Layers: These layers are used to provide the application-wide functionality and they can be re-used in different solutions. Example of layers are:
2- Vertical Layers: These are the layers which actually logically creates your application, for example, UI, business logic, data access and theoretically these layers can also be used in similar applications with some changes. Horizontal layers are used across by the vertical layers.