This is an PPT of DBMS.It include the following topic " Overview of 3-tier Client Server Architecture".

1. BIRLA INSTITUTE OF
TECHNOLOGY, MESRA
JAIPUR
Presented By
Anushka Pareek
MCA/25024/18
Yash Sogani
MCA/25025/18
TOPIC :OVERVIEW OF 3-TIER CLIENT
SERVER ARCHITECTURE

2. 3-TIER ARCHITECTURE
A three-way interaction in a client/server environment
where :
 User interface is stored in the client.
 Bulk of the business aplication logic is stored in one
or more servers.
 data are stored in a database server.

4. EVOLUTION TO THE 3-TIER ARCHITECTURE

5. 3-TIER ARCHITECTURE
 With the advent of Internet many people jumped to
the conclusion that the days of the mainframe were
back.
 Client/Server obviously failed, personal computers
had failed and Windows was on its way out.
 A host of “thin client” application where developed.
 Thus 3-tier applications were born

6.  This Application runs the traditional client / server
model but from a web server.

7.  The client only displays the GUI and data , but has
no part in producing results.

8. BENEFITS
SCALABILITY:
 The application servers can be deployed on many
machines.
 The database no longer requires a connection from
every client (only from a smaller number of
application servers).
 TP monitors or ORBs can be used to balance loads
and dynamically manage the number of application
server(s) available.

9. BENEFITS
BETTER RE-USE:
 If an estandard object is employed, the specific
language of implementation of the middle tier can
be made transparent.
IMPROVE DATA INTEGRITY:
 The middle tier can ensure that only valid data is
allowed to be updated in the database.

10. BENEFITS
IMPROVED SECURITY:
 Since the client doesn’t have direct access to the
database.
 Business Logic is generally more secure since it is
placed on a more secure central server.
REDUCED DISTRIBUTION:
 Changes to business logic only need to be updated
on the application servers and do not have to be
distributed to all the clients.

11. BENEFITS
IMPROVED AVAILABILITY:
 Mission-critical applications can make use of
redundant application servers and redundant
database servers, so it can recover from network or
server failures.
HIDDEN DATABASE STRUCTURE :
 Since the actual structure of the database is hidden
from the caller.

12. DRAWBACKS
INCREASED COMPLEXITY/EFFORT:
In general is more difficult to build a 3-tier
application compared a 2-tier application because:
 The points of communication are doubled.
 Many handy productivity enhacements provided by
the client tools will be foregone or their benefit will be
reduced.
FEWER TOOLS:
 The existence of more tools available for a 2-tier
model (e.g. most reporting tools).

13. ADVANTAGES OF THE 3-TIER ARCHITECTURE
APPROACH :
o the ability to separate logical components of an
application ensures that applications are easy to
manage and understand.
i.e. experts can be employed that specialise in one of
the layers e.g. user interface design
o because communication can be controlled between
each logical tier of an application, changes in one tier,
for example, the database access tier, do not have to
affect the client component
i.e. a change from one DBMS to another would only
require a change to the component in the data access
layer with little or no effect on the business/logic (middle)
or UI layer.
o specific tools and technologies suited to each layer
can be deployed (and may evolve at a different pace) .

14. CONCLUSION
 Complex application rules easy to implement in
application server.
 Business logic off-loaded from database server and
client, which improve performance .
 Changes to business logic automatically enforce by
server .
 Application server is portable to other database
server platforms by virtue of the application SW.
 Superior performance for medium to high volume
environments

15. THANK YOU