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  ETWORKI G

ESSE TIALS

PRESENTED TO:SIR ZEESHAN ABBAS

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RAMEENA JALIL 1421-315023ZARMEEN JALIL 1421-315024MUNEEB HUSSAIN 1421-315036MUDDASSIR AFSAR 1421-315047FAISAL KHAN 1421-315055

PRESENTED BY:

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OSI MODEL HISTORY AND BACKGROUND Why OSI was Created?

Advata!es O" OSI LAYERS O# OSI Sed$! % Re&e$v$! Order

NETWORK 'ROTOCOLS

Ty(es )" 'r)t)&)*s TC'+I' HISTORY O# TC'+I'

LAYERS O# TC'+I'

CONTENTS

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RAMEENA JALIL

1421-315023

ISO MODEL

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ISO-International Standard OrganizationISO is the Organization

OSI-Open System InterconnectionOSI is the Model

D!"#$%: I ,-../ 0ISO1 esta2*$shed a &)33$ttee t) deve*)( aar&h$te&t4re ")r &)3(4ter &)334$&at$)5

A$$!%: I ,-67/ the 0OSI1 re"ere&e 3)de* was a((r)ved as a$terat$)a* stadard ")r &)334$&at$)s ar&h$te&t4re5

Ter3 '#$()  de)tes the a2$*$ty t) &)e&t ay tw) syste3s wh$&h&)")r3 t) the re"ere&e 3)de* ad ass)&$ated stadards5

OSI M#%"

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Main idea in OSI is that the process of communication between two

end point in a telecommunication network can be divided into layers.

The OSI Model was created to Standardize the rule of in order for all

systems to be able to communicate OSI reference Model.

The OSI Model was esigned to !nsure different types of

!"uipment #$dapters% &outers% 'ubs ( )etwork $dopter*.

*+, OSI M#%"

./ C&.%

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A%!.(./

+rovide a ,ide ariety of hoice.

/ser can understand the ommon terms used in )etworking.

!ncrypt ata for Security +urpose.

It does not &elay on a Specific Operating System.

Interprets +roducts 0unctionality at each Stage.

It is !asier to add Multiple )etwork Models.

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 $ Set of layers and +rotocols is called )etwork $rchitecture.

7 Layers of OSI

  Why so Many Layers?

To reduce comple1ity% )etworks are organized as a Stack of

layers% one below the other.

!ach 2ayer +erforms a Specific Task.

This is similar to the oncept of a Function in programming

languages-0unction does a specific Task

Network Architecture

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MUDDASSIR AFSAR 

1421-315047

OSI LAERS

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Transmit Data Receie Data

!hysica" "ink

The Seen "ayers of OSI

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Specifications for the physical components of the )etwork.

Functions# 3it representation !ncode bits into electrical or optical signals.

Transmission rate the number of bits sent each second.

+hysical characteristics of Transmission media.

Synchronizing the sender and receiver clocks.

Transmission mode Simple1% half-duple1% full duple1.

+hysical topology 'ow devices are connected.

#&ing% Mesh% 3us Topology*

!hysica"

"ayer 

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&esponsible for delivery of data between two system

on the same network.

Function# 0arming divides the stream of bits received from network layer into

manageable data units called frames.

+hysical addressing add a header to the frame to define the physical

address of the source and the destination machines.

0low control impose a flow control-control rate at which data is

transmitted.

!rror control add mechanisms to detect and retransmit damaged or

lost frames.

Data "ink

Layer 

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&esponsible for delivery of packets across multiple

)etworks.

Functions# &outing-+rovide mechanisms to transmit data over independent

networks that are linked together.

&esponsible only for delivery of individuals packets and it does not

recognize any relationship between those packets.

Network

Layer 

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&esponsible for source to destination delivery of the entire

Message.

Function#

Segmentation and reassembly divide message into smaller

segments% numbers them and transmit. reassemble these messages

at the receiving end.

!rror control make sure that the entire message arrives without errors

retransmit.

Trans$ort

 Layer

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It is responsible for establishment of connections.

Function# ialog control-allows two systems to enter into a

  dialog% keep a track of whose turn it is to transmit

Synchronization-adds check points into stream of 

  data.

Session

Layer 

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&esponsibilities of this layer are4

Translation-ifferent computers use different encoding systems#bit

order translation*

onvert data into a common format before transmitting.

Synta1 represents info such as characters codes#how many bits

to represent data-5 or 6 bits*.

ompression reduce number of bits to be transmitted !ncryption-transform data into an unintelligible format at the sending

end for data security

ecryption-at receiving end

!resentation

Layer

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ontains protocols that allow the users to access the

network.#0T+%'TT+%SMT+*

Functions# oes not include application programs such as email% browsers% words

processing etc

+rotocols contain utilities and network-based services that supportservices.

  !mail via SMT+%

Internet access via 'TT+%

0ile transfer via 0T+

A$$"ication

Layer

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MUNEEB HUSSAIN

1421-315036

NET*ORK PROTOCOLS

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Network Protocol is a Set of Rules that Governs the

Communications between Computers on a Network.

What is Network !rotoco"s?

  &ules of )etwork +rotocol include guidelines that

&egulate the following characteristics of a network4

 $ccess method% allowed physical topologies% types

of abling% and speed of data transfer.

N%TWOR& !ROTO'OLS

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SMB: (Server Message Block)SMB 'r)t)&)* $s a etw)r8 "$*e shar$! (r)t)&)*/ ad as$3(*e3eted $ M$&r)s)"t W$d)ws $s 8)w as M$&r)s)"t

SMB 'r)t)&)*5

NFS: (Network File System)N#S $s a &*$et+server a((*$&at$) that *ets a &)3(4ter4ser v$ew ad )(t$)a**y st)re ad 4(date "$*e ) a

re3)te &)3(4ter as th)4!h they were ) the 4ser9s )w&)3(4ter5 The 4ser9s syste3 eeds t) have a NFS &*$etad the )ther &)3(4ter eeds the NFS server5

TPES OF PROTOCOLS

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TCPIP 

(Transmission Control Protocol/Internet Protocol)TC'+I' $s the 2as$& &)334$&at$) *a!4a!e )r (r)t)&)* )"the Iteret5 It &a a*s) 2e 4sed as a &)334$&at$)s(r)t)&)* $ a (r$vate etw)r8 0e$ther a $traet )r ae:traet15

SMTP

( Simple Mail Transfer Protocol) SMT+ is an Internet standard for electronic mail #email* transmission.

0irst defined by &0 578 in 8957% it was last updated in 7::5 with the!1tended SMT! additions by &0 ;

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ZARMEEN JALIL

1421-315024

TCPIP MODEL

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TC';Transmission Control Protocol  I';Internet protocol 

Deve*)(ed (r$)r t) the OSI 3)de*5

Layers )" TC'+I' d) )t 3at&h e:a&t*y w$th th)se $ the OSI3)de*5 Used $ the Iteret5 A2$*$ty t) &)e&t 34*t$(*e etw)r8s $ a sea3*ess way was

)e )" the 3a

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TCPIP L.,&/

ISO MODEL TCPIP

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FAISAL KHAN

1421-315055

TCPIP LAERS

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T)( 3)st *ayer )" ")4r *ayer TC'+I' 3)de*5 A((*$&at$)*ayer $s (reset ) the t)( )" the Tras()rt *ayer5

Th$s *ayer de"$es TC'+I' a((*$&at$) (r)t)&)*s ad h)w

h)st (r)!ra3s $ter"a&e w$th Tras()rt *ayer serv$&es t)4se the etw)r85

I&*4des a** the h$!her;*eve* (r)t)&)*s *$8e=

DNS 0D)3a$ Na3$! Syste31/ HTTP 0Hy(erte:t Tras"er

'r)t)&)*1/ T"( SSH FTP 0#$*e Tras"er 'r)t)&)*1/ TFTP 0Tr$v$a* #$*e Tras"er 'r)t)&)*1/ SNMP 0S$3(*e Netw)r8Maa!e3et 'r)t)&)*1/ SMTP 0S$3(*e Ma$* Tras"er'r)t)&)*1 / DHCP 0Dya3$& H)st C)"$!4rat$) 'r)t)&)*1/ *(%#/ RDP 0Re3)te Des8t)( 'r)t)&)*1 et&5

A$$"8.#( ".,&

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Tras()rt Layer $s the th$rd *ayer )" the ")4r *ayer TC'+I'3)de*5 The ()s$t$) )" the Tras()rt *ayer $s 2etweeA((*$&at$) *ayer ad Iteret *ayer5 The (4r()se )"

Tras()rt *ayer $s t) (er3$t dev$&es ) the s)4r&e addest$at$) h)sts t) &arry ) a &)versat$)5 Tras()rt *ayer de"$es the *eve* )" serv$&e ad stat4s )"

the &)e&t$) 4sed whe tras()rt$! data5

The 3a$ (r)t)&)*s $&*4ded at Tras()rt *ayer are TC'0Tras3$ss$) C)tr)* 'r)t)&)*1 ad UD' 0User Data!ra3'r)t)&)*15

T&.(/$#& ".,&

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Iteret Layer $s the se&)d *ayer )" the ")4r *ayerTC'+I' 3)de*5 The ()s$t$) )" Iteret *ayer $s 2etweeNetw)r8 A&&ess Layer ad Tras()rt *ayer5

Iteret *ayer (a&8 data $t) data (a&8ets 8)w as I'data!ra3s/ wh$&h &)ta$ s)4r&e ad dest$at$)address 0*)!$&a* address )r I' address1 $")r3at$) that$s 4sed t) ")rward the data!ra3s 2etwee h)sts ada&r)ss etw)r8s5 The Iteret *ayer $s a*s) res()s$2*e")r r)4t$! )" I' data!ra3s5

'a&8et sw$t&h$! etw)r8 de(eds 4() a &)e&t$)*ess$teretw)r8 *ayer5 Th$s *ayer $s 8)w as Iteret *ayer5Its

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Netw)r8 A&&ess Layer $s the "$rst *ayer )" the ")4r *ayerTC'+I' 3)de*5

Netw)r8 A&&ess Layer de"$es deta$*s )" h)w data $s

(hys$&a**y set thr)4!h the etw)r8/ $&*4d$! h)w 2$tsare e*e&tr$&a**y )r )(t$&a**y s$!a*ed 2y hardwaredev$&es that $ter"a&e d$re&t*y w$th a etw)r8 3ed$43/s4&h as &)a:$a* &a2*e/ )(t$&a* "$2er/ )r tw$sted (a$r&)((er w$re5

The (r)t)&)*s $&*4ded $ Netw)r8 A&&ess Layer areEtheret/ T)8e R$!/ #DDI/ >5@/ #ra3e Re*ay et&5

N#&9 A88// L.,&

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Thank

 You.