The document discusses different types of client-server architectures. A 1-tier architecture has the database directly available to users on one machine with no network. A 2-tier architecture connects multiple clients directly to a database server over a network. A 3-tier architecture adds an application server layer between clients and the database server to improve scalability, security, and data integrity for large web applications.

1. Presentation
on
Client Server Architecture

2. Client /Server Architecture
• The basic client/server architecture is used to deal with a large
number of PCs, web servers, database servers and other components
that are connected with networks.
• The client/server architecture consists of many PCs and a workstation
which are connected via the network.
• Client requests the server for a service. Server provides the requested
service to the client.

3. Client /Server Architecture
CClient
Client
Client
Network Server

4. Types of Client/Server Architecture
• Client/Sever architecture can be seen as a single tier or multitier.
DC/S Architecture Types
1-tier Architecture 2-tier Architecture 3-tier Architecture

5. Single or 1-tier Architecture
• In a single or 1-tier architecture, the database is directly available to
the user. The client, server and database all reside on the same
machine i.e. the user can directly sit on the DBMS and uses it.
• Any changes done here will directly be done on the database itself. It
does not provide a handy tool for end users.
• No network connection is required to perform the action on the
database.

6. Use: 1-tier architecture
• Where data does not change frequently and where no multiple user is accessing
the system.
• For the development of the local application, where programmers can directly
communicate with the database for quick response.
• But such architecture is rarely used in production.
1-tier architecture
Database user
database system

7. 2-tier architecture
Network Connection
• It is same as the client server.
Client 1 Client 2 Client 3
Data
Server

8. 2-tier architecture
• In the 2-tier architecture, applications on the client end can directly communicate
with the database at the server side.
• An Application Programming Interface(APIs) like ODBC( Open Database
Connectivity) and JDBC(Java Database Connectivity) are used by client side
programs to call the DBMS.
• The user interface and application programs are run on the client side.
• To communicate with the DBMS, client side application established a connection
with the server side.
• The server side responsible to provide the functionalities like query processing
and transaction management.

9. Use: 2-tier architecture
• The 2-tier architecture is used inside any organization, where multiple clients accessing
the database server directly.
E.g. customer can withdraw the money from the bank counter where teller as a
client accesses the bank database server directly.
Advantages:
• Direct and faster communication.
• Maintenance and understanding is easier.
• Compatible with existing system.
Disadvantages:
• it gives poor performance when there are a large number of users.
• Less secure as client can access the server directly.

10. 3-tier architecture
Client Layer
Client
Application
Business Layer
Data Layer
Client 1 Client 2 Client 3
Application server
Data
source

11. 3-tier architecture
• 3-tier architecture contains another layer of application server between the client
and database server.
• In this architecture, client can’t directly communicate with the database server.
• The application on the client end interacts with an application server which
further communicates with the database server and then query processing and
transaction management takes place.
• The intermediate layer of application server acts as a medium for exchange of
data between the database server and client.

12. 3-tier architecture
• End user has no idea about the existence of the database beyond the application
server. The database server also has no idea about any other user beyond the
application.
Uses of 3-tier architecture
• The 3-tier architecture is used in large web applications.
• It is the most popular DBMS architecture.
Advantages
• Enhanced scalability due to distributed deployment of application server.
• Data integrity is maintained. Since there is a middle layer between client and
database server, data corruption can be avoided /removed. (Data integrity refers
to accuracy and consistency of data stored in the database.)

13. 3-tier architecture
• Security is improved. This type of model prevents direct interaction of the client
with the database server there by reducing the access to unauthorized data.
Disadvantages
• Increased complexity of implementation and communication. It becomes difficult
for this sort of interaction to take place due to presence of middle layer.