Thin and Fat Client Model

There are two type models of the client-server architecture.

Thin-client model
In a thin-client model, all of the application processing and data management is carried out on the server. The client is simply responsible for running the presentation software.

Fat-client model
In this model, the server is only responsible for data management. The software on the client implements the application logic and the interactions with the system user.



Thin CLient Model:
-Used when legacy systems are migrated to client server architectures.
-The legacy system acts as a server in its own right with a graphical interface implemented on a client.
-A major disadvantage is that it places a heavy processing load on both the server and the network.

Fat Client Model:

-More processing is delegated to the client as the application processing is locally executed.
-Most suitable for new C/S systems where the capabilities of the client system are known in advance.
-More complex than a thin client model especially for management. New versions of the application have to be installed on all clients.

Client Server Model

-Distributed system model which shows how data and processing is distributed across a range of components.
-Set of stand-alone servers which provide specific services such as printing, data management, etc.
-Set of clients which call on these services.
-Network which allows clients to access servers.



-The application is modelled as a set of services that are provided by servers and a set of clients that use these services.
-Clients know of servers but servers need not know of clients.
-Clients and servers are logical processes
-The mapping of processors to processes is not necessarily 1 : 1.

A client-server system:



Computers in C/s network: