Question

what is the difference between 3 tier architecture and a mvc ?

Are they same?

Both have 3 layers i.e model, views and controller

Answer 1

Comparison with the MVC architecture

At first glance, the three tiers may seem similar to the
model-view-controller (MVC) concept; however, topologically they are
different. A fundamental rule in a three tier architecture is the
client tier never communicates directly with the data tier; in a
three-tier model all communication must pass through the middle tier.
Conceptually the three-tier architecture is linear. However, the
[model-view-controller] MVC architecture is triangular: the view sends
updates to the controller, the controller updates the model, and the
view gets updated directly from the model.

Source: http://en.wikipedia.org/wiki/Multitier_architecture#Three-tier_architecture