I was wondering what exactly is the difference between MVC(which is an architectural pattern) and an n-tier architecture for an application. I searched for it but couldn't find a simple explanation. May be I am a bit naive on MVC concepts, so if anyone can explain the difference then it would be great.
cheers
Give yourself a break. And don't restrict yourself to certain patterns when solving real-world problems. Just remember some general principles, one of which is SEPARATION OF CONCERNS.
N-tier architecture usually has each layer separated by the network. I.E. the presentation layer is on some web servers, then that talks to backend app servers over the network for business logic, then that talks to a database server, again over the network, and maybe the app server also calls out to some remote services (say Authorize.net for payment processing).
MVC is a programming design pattern where different portions of code are responsible for representing the Model, View, and controller in some application. These two things are related because, for instance the Model layer may have an internal implementation that calls a database for storing and retrieving data. The controller may reside on the webserver, and remotely call appservers to retrieve data. MVC abstracts away the details of how the architecture of an app is implemented.
N-tier just refers to the physical structure of an implementation. These two are sometimes confused because an MVC design is often implemented using an N-tier architecture.
This is what say about n-tier architecture
Besides being linear, another major difference that was not emphasized enough here is that in the N-tier model, N is not necessarily 3-tiers! It is most often implemented as three tiers (presentation, app, data) with the middle layer having two sub-tiers (business logic and data access). Also, the model in MVC can contain both data and business logic for data manipulation, whereas these would be in separate tiers in n-tier.
@Cherry Middle ware works more like a request handler or redirector in MVC Pattern.
I would like to explain a bit about MVC, According to me Model View Controller works like this.
That's all about MVC that i know.
Jerry: Here's a simple example of how the two are related:
Tier 1 - Consists of Models that communicate with Tier 2 through some sort of network service or similar, controllers to handle input validation, calculations and other things relevant for the views. And it contains the views themselves, ofcourse - which can be the GUI in a desktop-app, or the web-interface in a web-app.
Tier 2 - Contains some sort of service or other way of recieving messages from Tier 1. Does not/should not know about Tier 1, so can only answer to calls from above - never ask for things by itself. Also contains all business-logic.
Tier 3 - Contains the domain model, object representation of the database and all logic to communicate and update database-entries.