OSI Model And Discriptions

2. • OSI (Open Systems Interconnection) is reference model
for how applications can communicate over a network.
Helps understanding relationships of communicating
devices in conceptual framework.
Provides guideline for vendors and developers to
create products (soft wares and hard wares) to
communicate.
Facilitate clear comparisons among communications
tools.
Rarely used model but useful to understand network
infrastructure.

3.  Explain the role of protocols in supporting
communication between server and client
processes.
 Describe the features, operation, and use of
well-known TCP/IP application layer services
(HTTP, DNS, SMTP).

4.  Data can be represented in different manner
in different OS’s and hard wares. It is the
responsibility of presentation layer to
represent data for both sender and receiver.
Define the format of the data:
VIDEO, AUDIO, TEXT, IMAGE etc

5.  Establishes, maintains, and terminates user
connections.

6.  Transport layer is responsible for delivering
data to destination in a error free manner.
 Segmentations.

7.  Network layer performs routing.
 IP addressing (logical addressing) is
performed on this layer.
 End device to an other device delivery of
packets.

8.  The errors are corrected on this layer.
 How to convert data from bit to frames.
 Sequence of frames.

9.  On this layer we determine how the network
is physically networked.
 what kind of NIC is used.
 what sort of cables are used.
 How the data will be transmitted.

10. 7
• Application layer
6
• Presentation layer
5
• Session Layer
4
• Transport Layer
3
• Network Layer
2
• Data link layer
1
• Physical Layer

11. 7
• Application layer
6
• Presentation layer
5
• Session Layer
4
• Transport Layer
3
• Network Layer
2
• Data link layer
1
• Physical Layer

12. 7
• Application layer
6
• Presentation layer
5
• Session Layer
4
• Transport Layer
3
• Network Layer
2
• Data link layer
1
• Physical Layer

13. 7
• Application layer
6
• Presentation layer
5
• Session Layer
4
• Transport Layer
3
• Network Layer
2
• Data link layer
1
• Physical Layer

14. 7
• Application layer
6
• Presentation layer
5
• Session Layer
4
• Transport Layer
3
• Network Layer
2
• Data link layer
1
• Physical Layer

15. 7
• Application layer
6
• Presentation layer
5
• Session Layer
4
• Transport Layer
3
• Network Layer
2
• Data link layer
1
• Physical Layer

16. 7
• Application layer
6
• Presentation layer
5
• Session Layer
4
• Transport Layer
3
• Network Layer
2
• Data link layer
1
• Physical Layer

18. 1
• Application layer
2
• Presentation layer
3
• Session Layer
4
• Transport Layer
5
• Network Layer
6
• Data link layer
7
• Physical Layer DSL, ISDN, ATM
ARP
IP, DHCP,
TCP, UDP
DNS, SSL
3270 Data stream
HTTP. FTP, SMTP

19. ?