The document discusses client-server architecture. It describes the basic components of client-server systems including clients that make requests, servers that process requests and return responses, and a communication network that connects them. It outlines two main types of client-server architectures: 2-tier with a direct client-server connection, and 3-tier with middleware between the client and server. The document also distinguishes between thin and thick clients, iterative and concurrent servers, and three common client-server models.
2. CLIENT- SERVER ARCHITECTURE
• It refers to the two processes or
two applications which
communicate with each other to
exchange some information.
• Most of the net applications use
the client server architecture.
3. CLIENT-SERVER ARCHITECTURE
: COMPONENTS
• CLIENT: It makes a request for information. Eg:
internet browser works as a client application
which sends a request to web server to get one
HTML web page.
• SERVER: It takes request from the client and
do required processing and gather requested
information and sends it to the client. Eg: web
server keeps waiting for requests from internet
browsers and when it gets any request from a
browser it picks up the HTML page and sends it
back to that browser.
4. COMPONENTS CONTD.
• COMMUNICATION NETWORK: It
connects client and server.
Client -Server Architecture
REQUEST
CLIENT NETWORK SERVER
RESULTS
5. CLIENT SERVER ARCHITECTURE: 2 TYPES
2-TIER ARCHITECTURE
• It has got only client and server.
• Client directly interacts with the server.
• This may have some security holes and
performance problems.
CLIENT SERVER
6. TYPES CONTD.
3-TIER ARCHITECTURE
• In this one software sits in between client and
server. This middle software is called middleware.
• Middleware takes all requests from the client and
after doing required authentication it passes that
request to the server. Then server does required
processing and sends response back to
middleware and finally middleware passes this
response back to the client.
• More secured than 2-tier.
CLIENT MIDDLEWARE SERVER
7. SERVERS: 2 TYPES
• ITERATIVE SERVER: It can handle only
one client or request at a time.
Meanwhile another client keeps waiting.
• CONCURRENT SERVER: It can handle
multiple requests at the same time.
8. CLIENTS: 2 TYPES
• THIN CLIENT: The client has only
presentation layer and it has to
depend on the server
completely.
• THICK CLIENT: The client has
both application and
presentation layer and is less
dependent on the server.
PRESENTATION
LAYER
APPLICATION
LAYER
PRESENTATION
LAYER
9. CLIENT- SERVER MODELS
1)DUMB MODEL
• Client has no logic like application or
presentation layer.
• Request is sent as keystrokes.
• Server processes it and sends it in a
displayable form.
KEYSTROKES
CLIENT NETWORK SERVER
DISPLAY
10. 2)TRUE C-S MODEL
• Client has presentation layer.
• Request is sent as keystrokes.
• Server processes it and sends the processed
results.
CLIENT
NETWORK
KEYSTROKES
PRESENTATION SERVER
PROCESSED
RESULT
11. 3)DISTRIBUTED C-S MODEL
• Client has both application and presentation
layer.
• Request is sent as processed query and server
sends back processed results.
APPLICATION
PRESENTATION
NETWORK SERVER
CLIENT PROCESSED
QUERY
PROCESSED
RESULT
12. REFERENCE
• Client server model –architecture,
tutorialspoint.
• Client- Server architecture by Vangie
Beal. Webopedia.