classate
Application Layen Date
Page.
Wonld wide aleb was cheated by Timnothy
SenneS | ee
WWw 1 a collection of oebsite oh,
on web
pages stohed oneb seNes qnd Connected
to local (omputers hu he inteAnet
Ihe ocb paqes ane designed in HIML and
connected by links called ypenText. Thesc
hype links qcce ssed by HTTP.
Aieb paye is ien an online addneSs
callcd URL. Exo h . com
Reuest fol Reguest fon
Intenet webpaj
welb Pye webp43e
Htm file HImL le
Web bnow Ser
(client)
KDomain Nane System (DNS):
seNvice that phovides
DNS
bl
s.
the name (oebsite cnd itsmaping
numeical IP adDess
X.con I19.252.152.154
clssate.
Date
Page
Recunsive:
Root
3
loccal
client
Cache Top Dormain
tevet
DNS Resolven
4
Auth
Iteative
HITP:
It is a photocol used to access the dat ont the
Pont no. s0.
Uses TCP to acbieve neliabilty
Stuteless HITP
is a stutelss photococlient
and sesve Do) ech othe
know on the
cuent hequest Both dient and sNe dusing
not hetuin the nfo b/o Noniy hequest
of the oeb
Inband photocol Genchates cormands data
fhom sam pont
classHate
Date
Page
’Htte 1.0 Non pensistent connection
Htte 11 i peisten cobnection
Multtiple connections Pessistent connections
clhent Sehve client SeSue
open
time
doye
Fi? (Ee Ihansfen thotocol):
Netwohk pootocol fon thansnittiny iles blw
TCP TP connectionS
->Reliable phstocol
Not inbund pont no, 20 to datu and 21
fo (ontol
fenttions Commandí ke uwe
identitication cnd passNd.
>Dutu connection is non- pchsistemt
(onthol (onnetion is pehsistent
Stuteful
ARemote Logic Photacol
COmmand
alassmate
Data
( Page
Remote lgaic photacol, alloing Uses to
access
to a hemote host machinc and wwe thc\
tenminals ected
(onnected to the netwnhks
TELNET CTemi nal Netwok)
TELNEL Commurd line to connect cwth
ComputeNs client Uses TELNET to ping q paht
and find out weatheit is open FIR (am
also be used alongQith Telnet to send data
fles alog
Client cntes thein
thein wwename cmd
to acLeSS the hemote computen
Telnet is not a secunc pnetoco cnd is um
enchypLed. By monitohing a. usEN'S rtunDectio,
anyone accessS person
passoohe and othen phivate nfo. that
is typed oue the Te\ net scssion in plaintext
SSH (Secuye shell)
Seme modesn systems enable Commamd linc
Connections using SsH, an enchyptcd to ol
similan to Telnet, ro VeN Now,
use SSH, PuT7Y oh othe options
instead of Telnet. ssH iJ the mast
ued commony
all
oltenative, Lwyey bcz it ênchypts
the thatfic that passes Oye the comm.
channel
cassHate
Dafe
Page
1Email
X
Photocol:
Email Photocols colection of phsta (ols.
that Ne Ued tosend and ne ceiNe emails
phopealy.
Email photo cols ane a set ot command fan
shaning mals blu2 computes
By the use at cmail pasto cols client can
thansmit the mail to on fhom theintend edl
malSeen
’ Ernatl phsto cols cstablish comm blw th Sende
nd neceiNen to the thansmi csion ot emca
Ihehc anhe 3 basic typss st emaul photocolsi
SMTP (Simele Mail Ihuns fes Raoto col):
Sinplc mail thunste Photoco is used to
Stnd mails OVS the inteanet
SMIP Alonnection oniented nd text based
photocol
’ (ompanics ye thei SMTP Seve ton email
monketnà foh sendint uto mated thdnsactin
ernails passond chanj phorns tiohal and
thuns actional cmailtc
classMAte
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Pont 25i Default un- cnoypted poht
Pont 2525open at seueN side
Pont u65: Enypted pont
SMTP
client Server
POP3/IMAP
Multipunpose Irtenet Mail Extension (MIME)Patoc:
It is able to send mutiplec attachmen oith
single ms
It can send exe utables imgges, audio videa
fles o Bimany.
bUnlimited Message lengin
MIME Heades
MIME vehsion) Detnes theNosion ot the Notocol.
Content tyee: Iype ot datq used in the body
of the msg ike text audio oN Video
Content
Sortent type knadin Methad ucd fo encodin
the ms)
Content Id : Used fon niquely identitying the ma)
Cortent desc: befincs ohethen the body attucly
awdio.
2)Past office Photoco) (pop):
Ne
’Used to netheNe emil fon asingle clicnt
cassmate
Date
Page
POP3 veSSion is the cuNNnt Veh sin of POP UJed
’It allaws to acess mail offline lo accesL
the tn it has to be downloadcd.
PoP alloJS only a singlc mailbO X to be
Cheated on themail sewen,
POP
does not allqu Seanch fuilities
Pont \o Un-cnoypted pot
PoNt qAS En(Hpted poht
3) MAP (Inteanct Mag Acess Potocol)
’IMAP is uucd to netnieye mals fon multiplc
cienty
These Se seNeAal IMAP Mesions: IMAPIMAP
3 L ete
IMAP allos to emal wdb downloadins
them nd also upponts emal daonload
maintained by nemote sees
t enables al emails ope,ctiong such as
Cheate, manipulate cand delete the cma
colo neadin it
It allows yoy to Jeanch cmails.
’ t allaus to multiple meil bOxes to be
Cheated on multlple mail seNU Cmd
allou
Un-encypte paht
Pant 993: Encsypted pant
