The document discusses client-server networks. In a client-server network, computers are either clients or servers. Servers provide services and control access to hardware/software resources, storing programs, data, and handling user authentication and access to stored files. Clients request resources from servers and can get, send, delete or modify files on a server. Different types of servers include application servers, message servers, proxy servers, database servers, web servers, and others like FTP, mail, virtual, telnet and news servers. Client-server networks have advantages like reducing traffic and providing faster responses, security and accessibility, but disadvantages include costs, single point of failure if server fails, and need for professionals for maintenance. An example of

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2. Client-Server Network
 A network
which consist of clients and servers.
 A network
architecture in which each computer or
process on the network is either a client or a server.
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3. Server:
 Provides
services for clients.
 Also known as host computer.
 Controls access hardware and
software on the network.
 Provide storage area for programs,
data and information.
 User authentication and registration.
 Provide access to stored data…
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4. Client:
 Also
known as users or customer.
 Request the resources from the
server.
 Independent from other clients.
 Gets the files from server.
 Sends file to the server.
 Delete, copy, Rename the files on the
server….
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5. Types Of Servers:


Application server:
Dedicated to run different
applications.
Message Servers:
Include chat rooms, group
wares, provide instant and real time
communication between users.

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6. Types of Servers Cont….



Proxy Server:
Used to filter request made by user
over the server.
Improves performance.
Database Server:
 Manages database used over the
network.

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7. Types of Servers Cont….



Web Server:
Provides access to internet via HTTP.
Receives request from browser and
sends to main server….
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8. Other Types of Servers.






File Transfer Protocol Server (FTP)
Mail Server
Virtual Server
Telnet Server
News Server
List Server
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9. Advantages:
Reduces the volume of data traffic
over the network.
 Provides faster response to clients.
 Allows the use of less powerful
computers as clients because most of
the work is done by server.
 Provides more security.
 Accessible any time.

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10. Disadvantages:
Expensive model.
 Operations stop across the network if
server goes down.
 Need of professionals to maintain.
 No robustness.
 Difficult to implement than P2P.

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11. Example:

Online Banking networks.
User wants to access his account
from the web browser. As his data is
stored in database, web server run a
program to access database. This
database server may, in turn,
fetch financial transaction records from
another database server. An application
server interprets the returned data by
following the bank's business logic, and
provides the output to the web server.
Finally, the web server sends the result
to the web browser, which interprets the
data.
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12. Comparison with P2P network
Clients Server consist of many clients
but P2P consist of one client one
server.
 Computing power, memory and
storage is more than P2P.
 Scaled properly to perform any
process on any query.

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