The presentation describes OSI reference model along with TCPIP comparison.

1. The OSI Model and the TCP/IP Protocol Suite
Ramesh Kumar – Research Engineer, Convergence Labs

2. The OSI model
FTP, HTTP, Telnet
JPEG, MPEG, PDF
BIOS, NetBIOS, NetBEUI
TCP, UDP, SCTP
IP, OSPF, RIP, BGP - 4
ATM, FR, Ethernet
RS-232, RJ-45, V.35
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6
5
4
3
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1 Physical
Datalink
Network
Transport
Session
Presentation
Application
1 Physical
2 Datalink
3 Network
4 Transport
5 Session
6 Presentation
7 Application

3. The OSI model
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4
3
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1 Physical
Datalink
Network
Transport
Session
Presentation
Application
1 Physical
2 Datalink
3 Network
4 Transport
5 Session
6 Presentation
7 Application
Application Layer
i s t h e L a y e r
t h r o u g h u s e r
interacts with the
network.
The Protocols at
Application Layer
include HTTP,
Telnet, Ftp, DNS,
TFTP, Smtp etc.

4. The OSI model
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5
4
3
2
1 Physical
Datalink
Network
Transport
Session
Presentation
Application
1 Physical
2 Datalink
3 Network
4 Transport
5 Session
6 Presentation
7 Application
P r e s e n t a t i o n
L a y e r i s
responsible for
encoding and
decoding of user
data.
The presentation
layer protocols
include JPEG,
MPEG, GIF, TIFF,
RTF etc.

5. The OSI model
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6
5
4
3
2
1 Physical
Datalink
Network
Transport
Session
Presentation
Application
1 Physical
2 Datalink
3 Network
4 Transport
5 Session
6 Presentation
7 Application
T h e p r i m a r y
p u r p o s e o f
Session Layer is
t o e s t a b l i s h ,
m a n a g e , a n d
t e r m i n a t e
s e s s i o n s
between various
applications.

6. The OSI model
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6
5
4
3
2
1 Physical
Datalink
Network
Transport
Session
Presentation
Application
1 Physical
2 Datalink
3 Network
4 Transport
5 Session
6 Presentation
7 Application
Transport Layer
is responsible for
true end to end
c o n n e c t i o n
management by
giving connection
o r i e n t e d a n d
connection less
services. It will
also take care of
flow control and
error control.

7. The OSI model
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6
5
4
3
2
1 Physical
Datalink
Network
Transport
Session
Presentation
Application
1 Physical
2 Datalink
3 Network
4 Transport
5 Session
6 Presentation
7 Application
Network Layer is
responsible for
R o u t i n g o f
information end
to end.
T h e N e t w o r k
Layer only one
R o u t a b l e
Protocol called IP
and number of
Routing Protocols
like RIP, OSFP,
EIGRP, BGP etc.

8. The OSI model
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5
4
3
2
1 Physical
Datalink
Network
Transport
Session
Presentation
Application
1 Physical
2 Datalink
3 Network
4 Transport
5 Session
6 Presentation
7 Application
Datalink Layer
responsible for
synchronisation,
flow control and
error control.
The Protocols
include Ethernet,
Frame Relay,
To k e n R i n g ,
Token Bus, ATM,
PPP etc.

9. The OSI model
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6
5
4
3
2
1 Physical
Datalink
Network
Transport
Session
Presentation
Application
1 Physical
2 Datalink
3 Network
4 Transport
5 Session
6 Presentation
7 Application
Physical Layer is
responsible for
P h y s i c a l ,
Electrical and
M e c h a n i c a l
Specifications of
the Network.
It encodes binary
d a t a i n t o
electrical, optical
or other impulses
for transmission
over the network
medium.

10. OSI and The TCP/IP model
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1 Physical
Datalink
Network
Transport
Session
Presentation
Application
1 Physical
2 Datalink
3 Network
4 Transport
5 Session
6 Presentation
7 Application
Application
TCP
IP
Host - to - Network

11. To translate, encrypt,
and compress data
End user interacts with
this layer to get access to
network resources
To establish, manage,
and terminate sessions
To move packets from
source to destination; to
provide internetworking
To transmit bits over a
medium: To provide
mechanical and electrical
specifications
To provide reliable
process-to-process
message delivery and
error recovery
To organize bits into
frames; to provide hop-
to-hop delivery
Presentation
Session
Transport
Network
Datalink
Physical
Application
Summary of Layers