architecture - "Layers"和 "Tiers"之间有什么区别？

Question

“层”和“层”有什么区别？

Answer 1

Logical layers are merely a way oforganizing your code. Typical layersinclude Presentation, Business andData – the same as the traditional3-tier model. But when we’re talkingabout layers, we’re only talking aboutlogical organization of code. In noway is it implied that these layersmight run on different computers or indifferent processes on a singlecomputer or even in a single processon a single computer. All we are doingis discussing a way of organizing acode into a set of layers defined byspecific function.

Physical tiers however, are only aboutwhere the code runs. Specifically,tiers are places where layers aredeployed and where layers run. Inother words, tiers are the physicaldeployment of layers.

来源:Rockford Lhotka，Should all apps be n-tier?