Download - Inf1505 Study Notes 2012 Final
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INF1505
MIS2
UNISA BCOM
SEMESTER 1
2012
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ContentsFundamentals of Information Sstems !2""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""5
C#1 Information Sstems$ An O%er%ie& !2""""""""""""""""""""""""""""""""""""""""""""""""""""""""5
1 Com!uters and IS in 'ail (ife !)""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""5
2 Com!uter (itera* and Information (itera* !+"""""""""""""""""""""""""""""""""""""""""""5
, T-e Be.innin.$ Transa*tion /ro*essin. Sstems T/S !+""""""""""""""""""""""""""""+
) Mana.ement Information Sstems MIS !"""""""""""""""""""""""""""""""""""""""""""""""""+
5 Ma3or Com!onents of an IS !""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""+
+ Usin. IS and IT !10"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""4
T-e IT o6 Mar7et !15"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""11
C#2 Com!uters$ T-e Ma*-ines Be-ind Com!utin. !20"""""""""""""""""""""""""""""""""""12
1 'e8nin. a Com!uter !21"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""122 T-e #istor of Com!uter #ard&are !2)"""""""""""""""""""""""""""""""""""""""""""""""""""""12
, T-e /o&er of Com!uters !25""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""" 1,
) Com!uter O!erations !2+"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""" 1)
5 In!ut9 Out!ut9 and memor 'e%i*es !2+""""""""""""""""""""""""""""""""""""""""""""""""""""1)
+ Classes of Com!uters !,1""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""15
:-at is Soft&are !,2"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""1+
4 Com!uter (an.ua.es !,5""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""1+
C#, 'ata6ase$ Sstems9 'ata :are-ouses9 and 'ata Marts !,4""""""""""""""""""""14
1 'ata6ases !,;"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""14
2 (o.i*al 'ata6ase 'esi.n !)2""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""1;
, Com!onents of a 'BMS !)+""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""21
) Re*ent Trends in 'ata6ase 'esi.n and Use !)"""""""""""""""""""""""""""""""""""""22
5 'ata &are-ouses !);"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""2)
+ 'ata Marts !5,"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""2
C#) /ersonal9 (e.al9 Et-i*al9 and Or.anisational Issues of ISs !54""""""""""""""""""241 Ris7s Asso*iated &it- Information Te*-nolo.ies !5;""""""""""""""""""""""""""""""""""24
5 /ri%a* Issues !+1"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""2;
5 Et-i*al Issues of Information Te*-nolo.ies !+5"""""""""""""""""""""""""""""""""""""""2;
5 T-e Im!a*t of IT in t-e :or7!la*e !+;"""""""""""""""""""""""""""""""""""""""""""""""""""",1
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) O6sta*les to Usin.
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Fundamentals of Information Systems p2
CH1 Information Systems: An Overview p2
1 Computers and IS in Daily Life p4
lossary Des!ription
Information Sstems Broader in s*o!e t-an information
te*-nolo.ies
Information Te*-nolo.ies
MIS Mana.ement Information Sstem
/'A /ersonal 'i.ital Assistant
/OS /oint of Sale
U/C Uni%ersal /rodu*t Code
2 Computer Litera!y and Information Litera!y p"
no&led.e &or7ers need 2 t!es of 7no&led.e to 6e *om!etiti%e in t-e
&or7!la*e !+$
#nowled$e Des!ription
Com!uter litera* = S7ill in usin. !rodu*ti%it soft&are= Basi* 7no&led.e of -ard&are and
soft&are9 t-e internet9 and
*olla6oration tools and te*-nolo.ies
Information litera* = Understandin. t-e role of
information in .eneratin. and usin.
BI= BI is more t-an 3ust info9 it !ro%ides$
= #istori*al %ie&s= Current %ie&s= /redi*ti%e %ie&s
Of 6usiness o!erations and
en%ironments
:-at I need to 7no& a6out BI and transa*tion !ro*essin. sstems T/S !+$
#nowled$e area Des!ription
BI = BI is more t-an 3ust info9 it !ro%ides$= #istori*al %ie&s= Current %ie&s= /redi*ti%e %ie&sof 6usiness o!erations and
en%ironments
Transa*tion !ro*essin. sstems T/S = Fo*us on data *olle*tion and
!ro*essin.= Ma3or reason for usin. t-em is *ost
redu*tion
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no&led.e &or7ers s-ould 7no& t-e follo&in. !+$
% Item
1 Internal and e?ternal sour*e of data
2 #o& data is *olle*ted
, :- data is *olle*ted) :-at t!e of data s-ould 6e *olle*ted
5 #o& data is *on%erted to info and e%entuall to BI
+ #o& data s-ould 6e inde?ed and u!dated
#o& data and info s-ould 6e used to .ain a *om!etiti%e ad%anta.e
& '(e )e$innin$: 'ransa!tion *ro!essin$ Systems +'*S, p"
T!i*al *-ara*teristi*s of T/S !+$
% C(ara!teristi!
1 T-e o!erations are re!etiti%e9 or2 In%ol%e enormous %olumes of data
4 -ana$ement Information Systems +-IS, p.
MIS is an or.anised inte.ration of t-e follo&in. !$
% Item Des!ription +if any,
1 #ard&are In!ut9 out!ut9 memor
2 Soft&are Commer*ial9 in=-ouse9 or 6ot-
, Te*-nolo.ies
) 'ata5 /ro*esses Met-od for !erformin. a tas7 in a MIS
a!!
+ #uman elements desi.ned to
!rodu*e$ timel9 inte.rated9 rele%ant9
a**urate9 and useful info for de*ision=
ma7in. !ur!oses
Users9 !ro.rammers9 sstems
analsts9 and ot-er te*-ni*al
!ersonnel
Tas7s in%ol%ed in desi.nin. a MIS !$
% 'as/ 1 'e8ne t-e sstems o63e*ti%es *learl
2 'ata must 6e *olle*ted and analsed
, Information must 6e !ro%ided in a useful format for de*ision=ma7in. !ur!oses
Or.anisations use info sstems to .ain a *om!etiti%e ad%anta.e"
0 -aor Components of an IS p.
In addition to -ard&are9 soft&are9 and -uman elements9 a MIS in*ludes ) ma3or*om!onents !$
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% Component
1 'ata
2 'ata6ase
, /ro*ess
) Information
5.1 Data p8
% Study note
1 T-e data *om!onent *onsists of ra& fa*ts and is *onsidered t-e in!ut to t-e
sstem
2 T-e info t-at users need ae*ts t-e t!e of data t-at is *olle*ted
, A data6ase is a *olle*tion of all rele%ant data or.anised in a series of
inte.rated 8les
) T-ere are 2 sour*es of data$
= Internal$ sales re*ords9 !ersonnel re*ords= 3ternal$ *ustomers9 *om!etitors9 su!!liers9 .o%ernment a.en*ies9
8nan*ial institutions9 la6our and !o!ulation statisti*s9 e*onomi*
*onditions
5 'ata -as a time orientation9 so$
= /ast data$ *olle*ted for !erforman*e re!orts= Current data$ *olle*ted for o!erational re!orts= Future data$ !redi*ted for 6ud.ets or *as- Go& re!orts
+ 'ata *an 6e *olle*ted in dierent formats$
= A..re.ated$ re!ortin. totals for *ate.ories of info= 'isa..re.ated$ itemised lists
/ros and *ons of t-e a..re.ated data format !4$
Format *ro Con
A..re.ate
d
Useful for re!ortin. o%erall
!erforman*e
(imits t-e a6ilit of t-e de*ision
ma7er to fo*us on s!e*i8*
fa*tors
5.2 Database p8
% Study note1 A data6ase is a *olle*tion of all rele%ant data or.anised in a series of
inte.rated 8les
2 A data6ase mana.ement sstem 'BMS is used to *reate9 or.anise and
mana.e data6ases
, 'ata6ases are also useful for redu*in. !ersonel time needed to .at-er9
!ro*ess and inter!ret data manuall
5.3 Process p9
% Study note
1 T-e !ur!ose of an ISs !ro*ess *om!onent is .eneratin. t-e most useful t!e
of info for ma7in. de*isions
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2 T-e !ro*ess *om!onent in*ludes$ transa*tion !ro*essin. re!orts and models
for de*ision analsis t-at *an 6e 6uilt into t-e sstem or a**essed from
e?ternal sour*es
5.4 Information p9% Study note
1 Info *onsists of fa*ts t-at -a%e 6een analsed 6 t-e !ro*ess *om!onent and
is an out!ut of an IS
2 'ata and information are dierent$
= Data$ *onsists of ra& fa*ts and 6 itself is diH*ult to use for ma7in.
de*isions= Information$ t-e out!ut of an IS *onsists of fa*ts t-at -a%e 6een
analsed 6 t-e !ro*ess *om!onent9 and are t-us more useful to t-e
MIS user
, T-e Dualit of info is determined 6 its usefulness to users9 and its usefulnessdetermined t-e su**ess of an IS
) Info is useful if it ena6les de*ision ma7ers to ma7e t-e ri.-t de*isions in a
timel manner
5 To 6e useful info must -a%e t-e follo&in. ualities$
5 'imeliness5 Inte$ration wit( ot(er data and information5 Consisten!y and a!!ura!y= 6elevan!e
+ If info la*7s t-ese Dualities t-e results are$
= In*orre*t de*isions
= Misallo*ation of resour*es= O%erloo7ed &indo&s of o!!ortunit
Informal info in*ludes$
= Rumours= Un*on8rmed re!orts= Stories
4 T-e ultimate .oal of an IS is to .enerate BI
; Information te*-nolo.ies su!!ort ISs and use t-e internet9 *om!uter
net&or7s9 data6ase sstems9 /OS sstems and radio freDuen* identi8*ation
RFI' ta.s
" 7sin$ IS and I' p18
% Study note
1 Information Sstems are desi.ned to$
= Colle*ted data= /ro*ess t-e *olle*ted data= 'eli%er timel9 rele%ant and useful info t-at *an 6e used for ma7in.
de*isions
2 To a*-ie%e t-is .oal9 an IS mi.-t use man dierent information te*-nolo.ies
6.1 The Importance of IS p11% Study note
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1 Info is t-e se*ond most im!ortant resour*e after t-e -uman element in an
or.anisation
2 Timel9 rele%ant9 and a**urate info is a *riti*al tool for en-an*in. a
*om!ans *om!etiti%e !osition and for mana.in. t-e ) Ms of resour*es
, '(e 4 -9s of resour!es:
= Man!o&er= Ma*-iner= Materials= Mone
Ma3or t!es of information sstems in*lude !11$
% IS Des!ription +if any,
1 /ersonnel information sstem /IS or
-uman resour*e information sstem
#RIS
= 'esi.ned to !ro%ide info t-at
-el!s de*ision ma7ers in
!ersonnel *arr out t-eir tas7smore ee*ti%el
= A /IS#RIS su!!orts t-e follo&in.
a*tions$o C-oosin. t-e 6est 3o6
*andidateo S*-edule and assi.n
em!loeeso /redi*t future !ersonnel needs
o Re!orts and stats on em!loee
demo.ra!-i*so Allo*ate -uman and 8n
resour*es
2 Intranet = A net&or7 &it-in an or.anisation
t-at uses internet !roto*ols and
te*-nolo.ies for *olle*tin.9
storin.9 and disseminatin. useful
info t-at su!!orts 6usiness
a*ti%ities su*- as sales9 *ustomer
ser%i*e9 -uman resour*es9 and
mar7etin.
= Intranets are !ri%ate, (o.isti*s information sstem (IS = 'esi.ned to$
o Redu*e t-e *ost of trans!ortin.
materials &-ileo Maintain safe and relia6le
deli%er= 'e*isions su!!orted 6 a (IS$
o Im!ro%e routin. and deli%er
s*-eduleso Sele*t t-e 6est modes of
trans!ortationo Im!ro%e trans!ortation
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% IS Des!ription +if any,
6ud.etin.o Im!ro%e s-i!ment !lannin.
) Manufa*turin. information sstem
MFIS
= 'esi.ned to mana.e
manufa*turin. resour*es so t-at
*om!anies *an$o Redu*e manufa*turin. *osts
o In*rease !rodu*t Dualit
o Ma7e 6etter in%entor
de*isions= Some de*isions t-at a MFIS
su!!orts$o Orderin. de*isions
o /rodu*t *ost *al*ulations
o S!a*e utilisation
o Bid e%aluation !ro*ess used
&it- %endors and su!!lierso Analsis of !ri*e *-an.es and
dis*ounts
5 Finan*ial information sstem FIS = 'esi.ned to !ro%ide info to
8nan*ial e?e*uti%es in a timel
manner= A FIS is used to su!!ort t-e
follo&in. de*isions$o Im!ro%e 6ud.et allo*ation
o Minimise *a!ital in%estment
ris7so Monitor *ost trends
o Mana.e *as- Go&s
o 'etermine !ortfolio stru*tures
+ Mar7etin. information sstems MIS = 'esi.ned to im!ro%e mar7etin.
de*isions= An ee*ti%e MIS s-ould !ro%ide$
o Timel9 a**urate9 and
inte.rated info a6out t-e
mar7etin. mi? pri!e
promotion pla!e and
produ!t= 'e*isions t-at a MIS su!!orts$
o Analse mar7et s-are9 sales9
and sales !ersonnelo Sales fore*astin.
o /ri*e and *ost analsis of items
sold
6.2 Using IT for a ompetiti!e "#!antage p13
% Study note
1 Mi*-ael /orter identi8ed , strate.ies for *om!etin. in t-e mar7et !la*e$
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= O%erall *ost leaders-i!= 'ierentiation= Fo*us
2 IT *an -el! 6ottom=line and to!=line strate.ies$
= )ottom5line$ fo*us on im!ro%in. eH*ien* 6 redu*in. o%erall *osts
= 'op5line$ fo*us on .eneratin. ne& re%enue 6 oerin. ne& !rodu*tsand ser%i*es to *ustomers or in*reasin. re%enue 6 sellin. e?istin.
!rodu*ts and ser%i*es to ne& *ustomers
, Sstems su*- as su!!l *-ain mana.ement SCM9 *ustomer relations-i!
mana.ement CRM9 enter!rise resour*e !lannin. ER/ *an redu*e *osts and
im!ro%e *ustomer ser%i*e"
) T-e .oal of t-ese sstems is to use IT to *reate t-e most eH*ient9 ee*ti%e
lin7 6et&een su!!liers and *onsumers
T!es of strate.ies in*lude !1,$
% Strate$y Des!ription +if any,
1 'ierentiation strate. = Or.anisation tr to ma7e t-eir
!rodu*ts and ser%i*es dierent
from t-eir *om!etitors= E?am!les$ A!!le9 AmaJon
2 Fo*us strate. = Or.anisations fo*us on a
s!e*i8* mar7et se.ment to
a*-ie%e a *ost or
dierentiation ad%anta.e
= E?am!le$ A!!le
6.3 Porter$s 5 %orces &o#e'( Un#erstan#ing the )*siness +n!ironment
p14
% Study note
1 /ur!ose of t-e 5 For*es frame&or7$
= Analsin. an or.anisation= Its !osition in t-e mar7et!la*e= #o& IS *ould 6e used to ma7e it more *om!etiti%e
2 T-e 5 for*es are as follo&s$
= Buer !o&er= Su!!lier !o&er= T-reat of su6stitute !rodu*ts or ser%i*es= T-reat of ne& entrants= Ri%alr amon. e?istin. *om!etitors
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*-oi*es9 lo& &-en *ustomers -a%e
fe& *-oi*es= 'ierentiation strate.
2 Su!!lier !o&er = #i.- &-en *ustomers -a%e fe&
o!tions9 lo& &-en *ustomers -a%e
more o!tions= 'ierentiation strate.
, T-reat of su6stitute !rodu*ts or
ser%i*es
= #i.- &-en man alternati%es to
an or.anisations !rodu*ts or
ser%i*es are a%aila6le
) T-reat of ne& entrants = (o& &-en du!li*atin. a
*om!ans !rodu*t or ser%i*e is
diH*ult= Fo*us strate.
5 Ri%alr amon. e?istin. *om!etitors = #i.- &-en man *om!etitors
o**u! t-e same mar7et!la*e9lo& &-en t-ere are fe&
*om!etitors
. '(e I' =o; -ar/et p10
Cate.ories of IT 3o6s !15$
% Cate$ory
1 O!erations and -el! des7
2 /ro.rammin.
, Sstems desi.n) :e6 desi.n and &e6 -ostin.
5 Net&or7 desi.n and maintenan*e
+ 'ata6ase desi.n and maintenan*e
Ro6oti*s and arti8*ial intelli.en*e
/o!ular IT 3o6s in*lude !15$
% Strate$y Des!ription +if any,
1 CTOCIO and sometimes C-ief /ri%a*
OH*er C/O
= (on.=ran.e !lannin.= ee!s an ee out on ne&
de%elo!ments in t-e 8eld= Mana.e ris7s and 6usiness
im!a*ts of !ri%a* la&s and
!oli*ies
2 Mana.er of IS Ser%i*es = #ard&are9 soft&are9 !ersonnel in
t-e IS de!artment
, Sstems Analst = 'esi.n and im!lementation of IS= ReDuires t-orou.- understandin.
of 6usiness sstems and
fun*tional areas &it-in a 6usiness
or.anisation
) Net&or7 Administrator = 'esi.n and im!lement net&or7
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CH2 Computers: '(e -a!(ines )e(ind Computin$ p28
1 De>nin$ a Computer p21
% Study note
1 A *om!uter is de8ned as a ma*-ine t-at$= A**e!ts data as in!ut= /ro*esses data &it-out -uman inter%ention 6 usin. stored
instru*tions a7a a K!ro.ram= Out!uts information
2
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transferred one 6it at a time= A !arallel !ort is an interfa*e 6et&een a *om!uter and a !rinter9 t-e
*om!uter transfers multi!le 6its of info to t-e !rinter simultaneousl
2 '(e History of Computer Hardware p24Learn ta;le 2a*uum tu6e ENIAC
Se*ond 1;5=1;+, Transistors IBM ;0)9 1)01
T-ird 1;+)=1;0 Inte.rated *ir*uits9
remote data entr9
tele*ommuni*atio
ns
IBM ,+09 ,0
Fourt- 1;1=1;;2 Miniaturisation9
%er lar.e s*ale
inte.ration >(SI9
!ersonal
*om!uters9 o!ti*al
dis7s
Cra QM/9 Cra II
Fift- 1;;,=!resent /arallel
!ro*essin.9
.allium arsenide
*-i!s9 o!ti*al
te*-nolo.ies
IBM Sstem J10
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= Millise*ond$ 119000 of a se*ond= Mi*rose*ond$ 1190009000 of a se*ond= Nanose*ond$ 11900090009000 of a se*ond= /i*ose*ond$ 119000900090009000 of a se*ond
, 'ata is stored in 6its$
= A 6it is a sin.le %alue of 0 or 1= 4 6its P 1 6te a 6te is t-e siJe of a *-ara*ter
) In a 6inar sstem$ 1 P on and 0 P o
5 Ameri*an Standard Code for Information Inter*-an.e ASCII$ most *ommon
data *ode for te?t 8les9 /C a!!li*ations9 and t-e internet i"e" used to
re!resent and transfer data 6et&een *om!uters and net&or7 sstems
+ ASCII$
= Ea*- al!-a6eti*9 numeri*9 or s!e*ial *-ara*ter is re!resented &it- a =
6it 6inar num6er= U! to 124 *-ara*ters *an 6e de8ned 2= Uni*ode and e?tended ASCII allo&s u! to 25+ *-ara*ters *an 6e
de8ned 24
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) = Random a**ess memor RAM$ %olatile memor a7a read=&rite memor= Read=onl memor ROM$ is non=%olatile data *ant 6e &ritten to ROM
5 Ca*-e RAM$ resides on t-e !ro*essor
5.2 -*tp*t De!ices p2
5.3 &emor, De!ices p28
5.3.1 &ain &emor, De!ices p28
% Study note
1 Most *ommon t!e of main memor is semi*ondu*tor memor *-i!s made of
sili*on it *an 6e$
= >olatile or= Non=%olatile
2 T-ere are 2 t!es of ROM$= /ro.ramma6le read=onl ROM /ROM$ *ontents *ant 6e erased on*e
&ritten= Erasa6le !ro.ramma6le read=onl ROM E/ROM$ as a6o%e 6ut
*ontents *an 6e erased and re!ro.rammed
5.3.2 Secon#ar, &emor, De!ices p28
% Study note
1 Non=%olatile and used for storin. lar.e %olumes of data for lon. !eriods
2 T-ere are , main t!es$
= Ma.neti* dis7s !2;$ data *an 6e a**essed in an order= Ma.neti* ta!e !2;$ stores data seDuentiall= O!ti*al dis7s !2;$ C'=ROMs9 :ORM dis*s9 and '>'s= SAN= NAS
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o Ta!e li6raries
o O!ti*al stora.e de%i*es
= Ma7es stora.e de%i*es a%aila6le to all ser%ers on a (AN or :AN= A SAN is a dedi*ated net&or7
2 NAS$
= Net&or7=*onne*ted *om!uter= 'edi*ated to !ro%idin. 8le=6ased data stora.e ser%i*es to ot-er
net&or7 de%i*es= Soft&are on t-e NAS -andles features su*- as$ data stora.e9 8le
a**ess9 8le stora.e9 and 8le mana.ement
" Classes of Computers p&1
% Study note
1 Com!uters are *lassi8ed 6ased on$
= Cost
= Amount of memor= S!eed= So!-isti*ation
2 Usin. t-e a6o%e *riteria *om!uters are *lassi8ed as$
= Su6=note6oo7s= Note6oo7s= /ersonal *om!uters= Mini=*om!uters= Mainframes= Su!er*om!uters
6.1 Ser!er P'atforms( "n -!er!ie0 p32
% Study note
1 A ser%er is a *om!uter and all t-e soft&are for mana.in. net&or7 resour*es
and oerin. ser%i*es to a net&or7
2 Some ser%er !latforms$
= A!!li*ation ser%ers= 'ata6ase ser%ers= 'is7 ser%ers= Fa? ser%ers= File ser%ers
= Mail ser%ers= /rint ser%ers= Remote a**ess ser%ers RAS= :e6 ser%ers
. ?(at is Software p&2
% Study note
1 Soft&are is all t-e !ro.rams t-at run a *om!uter sstem$
= Sstem soft&are$ e"." OS= A!!li*ation soft&are$ e"." a!!li*ations su*- as :ord and E?*el
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.1 -perating S,stem Soft0are p32
% Study note
1 A set of !ro.rams for *ontrollin. and mana.in. *om!uter -ard&are and
soft&are
2 An OS !ro%ides an interfa*e 6et&een t-e *om!uter and t-e users and
!erforms re!etiti%e tas7s, An OS *onsists of$
= Control !ro.rams= Su!er%isor !ro.rams
) Control pro$rams mana.e *om!uter -ard&are and resour*es 6
!erformin. t-e follo&in. fun*tions$
= o6 mana.ement$ *ontrol and !rioritise tas7s !erformed 6 t-e C/U= Resour*e allo*ation$ mana.e resour*es su*- as stora.e and memor or
assi.nin. !rint 3o6s in a net&or7= 'ata mana.ement$ *ontrol data inte.rit 6 .eneratin. *-e*7sums to
%erif a.ainst *orru!tion= Communi*ation$ *ontrol t-e transfer of data amon. !arts of a
*om!uter sstem
5 Supervisor pro$ram a7a t-e 7ernel$
= Res!onsi6le for *ontrollin. all ot-er !ro.rams in t-e OS= Su*- as$ *om!ilers9 inter!reters9 assem6lers9 utilities for !erformin.
s!e*ial tas7s
.2 "pp'ication Soft0are p33
@ Computer Lan$ua$es p&0
% Study note
1 Ma*-ine lan.ua.e
2 Assem6l lan.ua.e
, #i.-=le%el lan.ua.es
) Fourt-=.eneration lan.ua.es )
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CH& Data;ase: Systems Data ?are(ouses and Data -arts
p&@
1 Data;ases p&
% Study note1 A data6ase is a *olle*tion of related data t-at *an 6e stored in a *entral
lo*ation or in multi!le lo*ations
2 'ata -ierar*- is t-e stru*ture and or.anisation of data9 &-i*- in%ol%es
8elds9 re*ords9 and 8les
, = A data6ase mana.ement sstem 'BMS is soft&are for *reatin.9 storin.9
maintainin.9 and a**essin. data6ase 8les= A 'BMS ma7es usin. data6ases more eH*ient
) = @Flat 8les &ere not arran.ed in -ierar*- and -ad no relation to one
anot-er= T-e !ro6lem &as t-at t-e same data *ould 6e stored in more t-an 1 8le9
*reatin. data redundan*= 'ata mi.-t not 6e u!dated in all 8les *onsistentl9 resultin. in *onGi*tin.
re!orts .enerated from t-ese 8les= It *an 6e time *onsumin. to u!date a Gat 8le sstem
5 A data6ase -as t-e follo&in. ad%anta.es o%er a Gat 8le sstem$
= More info *an 6e .enerated from t-e same data= Com!le? reDuests *an 6e -andled more easil= 'ata redundan* is eliminated or minimised= /ro.rams and data are inde!endent9 so more t-an 1 !ro.ram *an use
t-e same data= 'ata mana.ement is im!ro%ed= A %ariet of relations-i!s amon. data *an 6e maintained easil= More so!-isti*ated se*urit measures *an 6e used= Stora.e s!a*e is redu*ed
Learn 3(i;it &
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1.2ðo#s for "ccessing %i'es p42
% A!!ess-et(od Des!ription Devi!e 7se
1 SeDuential
a**ess 8le
stru*ture
= Re*ords in 8les
are or.anised
and !ro*essed
in numeri*al or
seDuential
order9 t!i*all
t-e order in
&-i*- t-e
&ere entered= Re*ords are
or.anised
6ased on
@!rimar 7e
Usuall ma.neti*
ta!e
= Ee*ti%e &-en
a lar.e num6er
of re*ords are
!ro*essed less
freDuentl e"."
Duarterl or
annuall= A**ess s!eed is
not *riti*al
2 Random
a**ess 8le
stru*ture
Re*ords *an 6e
a**essed in an
order9 re.ardless of
t-eir !-si*al
lo*ation in stora.e
media
Ma.neti* dis7 Fast and ee*ti%e
&-en a small
num6er of re*ords
need to 6e
!ro*essed dail or
&ee7l
, Inde?edseDuential
a**ess
met-od
ISAM
= Re*ords *an 6ea**essed
seDuentiall or
randoml9
de!endin. on
t-e num6er
6ein. a**essed= It uses an inde?
stru*ture and
-as 2 !arts$ an
inde?ed %alueand a !ointer to
t-e dis7
lo*ation of t-e
re*ord
mat*-in. t-e
inde?ed %alue= Retrie%in. a
re*ord reDuires
at least 2 dis7
a**esses
For a smallnum6er9 random
a**ess is used9 and
for a lar.e num6er9
seDuential a**ess
is used
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2 Lo$i!al Data;ase Desi$n p42
% Study note
1 T-e p(ysi!al view in%ol%es -o& data is stored on and retrie%ed from stora.e
media9 su*- as -ard dis7s9 ma.neti* ta!es9 or C's
2 T-e lo$i!al view in%ol%es -o& info a!!ears to users and -o& it *an 6e
or.anised and retrie%ed T-e 8rst ste! in data6ase desi.n is de8nin. a data model
, A data model determines -o& data is$
= Created= Re!resented= Or.anised= Maintained
) A data model usuall *ontains$
= 'ata stru*ture$ des*ri6es -o& data is or.anised and t-e relations-i!
amon. re*ords= O!erations$ des*ri6es met-ods9 *al*ulations t-at *an 6e !erformed on
data9 su*- as u!datin. and Duerin. data= Inte.rit rules$ de8nes t-e 6oundaries of a data6ase9 su*- as ma? and
min %alues for a 8eld9 and *onstraints e"." &-at t!e of data *an 6e
stored in a 8eld9 and a**ess met-ods
5 Some e?am!les of t-e t!es of data models$
= Relational model= O63e*t=oriented model= #ierar*-i*al model= Net&or7 model
+ Hierar!(i!al model +3(i;it &
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% Study note
= 'efault %alues for 8elds= >alidation rules for data in ea*- 8eld
5 = E%er re*ord must 6e identi8ed 6 a primary /ey= *rimary /ey$ uniDuel identi8es e%er re*ord in a relational data6ase
= To esta6lis- relations-i!s amon. ta6les so t-at data *an 6e lin7ed andretrie%ed more eH*ientl9 a !rimar 7e for one ta6le *an a!!ear in ot-er
ta6les it is t-en *alled a forei$n /ey= Forei$n /ey$
o Field in a relational ta6le t-at mat*-es t-e !rimar 7e *olumn
of anot-er ta6leo It *an 6e used to *ross=referen*e ta6les
+ Bormalisation$
= Im!ro%es data6ase eH*ien* 6 eliminatin. redundant data= Ensures t-at onl related data is stored in a ta6le= Normalisation *an .o t-rou.- se%eral sta.es from 8rst normal form 1NF
to 8ft- normal form 5NF= Tas7s !erformed in a 1NF sta.e$
o Eliminate du!li*ated 8elds from t-e same ta6le
o Create se!arate ta6les for ea*- .rou! of related data
o Identif ea*- re*ord &it- a uniDue 8eld t-e !rimar 7e
= 'ata is retrie%ed usin. o!erations t-at !i*7 and *om6ine data from 1 or
more ta6les= T-ere are se%eral o!erations$
o Sele*t
o /ro3e*t
o oin
o Interse*to Union
o 'ieren*e
4 T-e most *ommonl used o!erations E?-i6its on !)5$
= Sele!t$ sear*-es data in a ta6le and retrie%es re*ords 6ased on *ertain
*riteria *onditions= *roe!t$ !ares do&n a ta6le 6 eliminatin. *olumns 8elds a**ordin.
to *ertain *riteria e"." a list of student 6ut &it-out t-eir a.es= =oin$ *om6ines 2 ta6les 6ased on a *ommon 8eld e"." !rimar 7e in
8rst ta6le and forei.n 7e in se*ond ta6le
& Components of a D)-S p4"
'BMS in*ludes t-ese *om!onents$
% D)-S Component
1 'ata6ase en.ine
2 'ata de8nition
, 'ata mani!ulation
) A!!li*ation .eneration
5 'ata administration
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3.1Database +ngine p46
% Study Bote
1 T-e data6ase en.ine is t-e -eart of a 'BMS and is res!onsi6le for$
= 'ata stora.e= Mani!ulation
= Retrie%al2 It *on%erts lo.i*al reDuests into t-eir !-si*al eDui%alents 6 intera*tin. &it-
*om!onents of t-e 'BMS usuall t-e data mani!ulation *om!onent
3.2Data Denition p46
% Study Bote
1 Used to *reate and maintain t-e data di*tionar and de8ne t-e stru*ture of
8les in a data6ase
2 T-is *om!onent is used for *-an.es to a data6ases stru*ture9 su*- as$
= Addin. or deletin. 8elds= C-an.in. a 8elds siJe= C-an.in. t-e data t!e stored in a 8eld
3.3Data &anip*'ation p46
% Study Bote
1 Used to add9 modif9 and retrie%e re*ords from a data6ase
2 T!i*all a Duer lan.ua.e is used for t-is *om!onent$
= Stru*tured uer (an.ua.e S($ *onsists of se%eral 7e&ords
s!e*ifin. a*tions
= uer B E?am!le BE$ reDuest data 6 *onstru*tin. a statementmade u! of Duer forms
, Basi* format of a S( Duer$ SE(ECT feld FROM table or fle :#ERE
conditions
3.4"pp'ication eneration p4
% Study Bote
1 Used to desi.n elements of an a!!li*ation usin. a data6ase$
= 'ata entr s*reens= Intera*ti%e menus
= Interfa*es &it- ot-er !ro.rammin. lan.ua.es
3.5Data "#ministration p4
% Study Bote
1 Used for tas7s su*- as$
= Ba*7u!= Re*o%er= Se*urit= C-an.e mana.ement= 'etermine &-o -as !ermission to !erform *ertain fun*tions9
summarised as$o Create
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% Study Bote
o Read
o U!date
o 'elete CRU'
2 'ata6ase administrator 'BA res!onsi6ilities$
= 'esi.nin. and settin. u! a data6ase= Esta6lis-in. se*urit measures to determine users a**ess ri.-ts= 'e%elo!in. re*o%er !ro*edures in *ase data is lost or *orru!ted= E%aluatin. data6ase !erforman*e= Addin. and 8ne=tunin. data6ase fun*tions
4 6e!ent 'rends in Data;ase Desi$n and 7se p4.
Re*ent trends in*lude$
% 'rend
1 'ata=dri%en &e6sites2 Natural lan.ua.e !ro*essin.
, 'istri6uted data6ases
) Clientser%er data6ases
5 O63e*t=oriented data6ases
4.1DataDri!en 7eb Sites p4
% Study Bote
1 Data5driven we;site$
= A*ts as an interfa*e to a data6ase9 retrie%in. data for users and
allo&in. users to enter data in t-e data6ase= Im!ro%es a**ess to info so users e?!erien*es are more intera*ti%e= Redu*es t-e su!!ort and o%er-ead needed to maintain stati* &e6 sites= C-an.es are made to t-e data sour*e9 not t-e &e6 site t-e &e6 site
ad3usts automati*all
2 /o!ular in$
= e=*ommer*e &e6sites= Ne&s sites= Forums and dis*ussion .rou!s= Su6s*ri!tion ser%i*es su*- as ne&sletters
4.2Distrib*te# Databases p48
% Study Bote
1 A distri;uted data;ase stores data on multi!le ser%ers t-rou.-out an
or.anisation
2 Se*urit issues are more *-allen.in. 6e*ause of multi!le a**ess !oints from
6ot- inside and outside t-e or.anisation9 t-e follo&in. items s-ould 6e
*learl de8ned$
= Se*urit !oli*ies= S*o!e of user a**ess
= User !ri%ela.es= Aut-orised users must 6e identi8ed
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% Study Bote
, Or.anisations mi.-t *-oose a distri6uted data6ase for t-e follo&in. reasons$
= T-e desi.n reGe*ts t-e or.anisations stru*ture 6etter e"." an
or.anisation &it- man 6ran*-es= (o*al stora.e of data de*reases res!onse time 6ut in*reases
*ommuni*ation *osts= 'istri6utin. data amon. multi!le sites minimises t-e ee*ts of
*om!uter failures= In*reased *a!a*it as o!!osed to onl 1 *om!uter ser%er= Se%eral small inte.rated sstems mi.-t *ost less t-an 1 lar.e sstem= Storin. data at remote sites *an -el! redu*e *osts for remote users= It is not limited 6 datas !-si*al lo*ation
) , a!!roa*-es to settin. u! a ''BMS *an 6e *om6ined$
= Fra.mentation= Re!li*ation= Allo*ation
5 Fra$mentation$= Addresses -o& ta6les are di%ided amon. multi!le lo*ations= #oriJontal fra.mentation 6rea7s a ta6le into ro&s9 storin. all 8elds
*olumns in dierent lo*ations= >erti*al fra.mentation stores a su6set of *olumns in dierent lo*ations= Mi?ed fra.mentation *om6ines %erti*al and -oriJontal stores onl
site=s!e*i8* data in ea*- lo*ation
+ 6epli!ation:
= Ea*- site stores a *o! of data of t-e or.anisations data6ase= Alt-ou.- it *an in*rease *osts9 it also in*reases a%aila6ilit of data= Ea*- sites *o! *an 6e used as a 6a*7u! for ot-er sites
Allo!ation:= Com6ines fra.mentation and re!li*ation= Ea*- site stores t-e data it uses most often= Im!ro%es res!onse time for lo*al users t-ose in t-e same lo*ation as
t-e data6ase stora.e fa*ilities
4.3'ientSer!er Databases p49
Users &or7stations *lients are lin7ed in a (AN to s-are t-e ser%i*es of a sin.le
ser%er"
4.4-bect-riente# Databases p49
% Study Bote
1 Re*a!$ a relational data6ase -as a sim!le stru*ture$ relations-i!s 6et&een
ta6les are 6ased on a *ommon %alue t-e 7e
2 O63e*t=oriented data6ases &ere de%elo!ed to address t-e in-erent !ro6lem
in relational data6ases i"e" re!resentin. more *om!le? data relations-i!s
sometimes isnt !ossi6le
, = (i7e o63e*t=oriented !ro.rammin.9 o63e*t=oriented data6ases re!resents
real &orld entities &it- data6ase o63e*ts
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% Study Bote
= An o63e*t *onsists of$o Attri6utes = *-ara*teristi*s des*ri6in. an entit
o Met-ods o!erations or *al*ulations t-at *an 6e !erformed on
t-e o63e*ts data
) E?am!le$= Class$ %e-i*le t-in7 of a *lass as a *ate.or or t!e of o63e*t= O63e*t$ *ar= Attri6utes$ ear9 ma7e9 model9 li*ense num6er= Met-od$ add>e-i*le
5 n!apsulation:
=
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% Study Bote
used for *a!turin. and mana.in. transa*tions
, T-e ) ma3or *om!onents of a data &are-ouse *on8.$
= In!ut= E?tra*tion
= Transformation= (oadin. ET(
5.1Inp*t p5
% Study Bote
1 Can *ome from a %ariet of data sour*es$
= E?ternal data sour*es= 'ata6ases= Transa*tion 8les= Enter!rise Resour*e /lannin. ER/ sstems$ *olle*t9 inte.rate9 !ro*ess
data= Customer relations-i! mana.ement CRM sstems$ *olle*t and
!ro*ess data
5.2+:traction; Transformation; an#
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% Study Bote
= Metadata$ info a6out data su*- as *ontent9 Dualit9 *ondition9 ori.in
et*"
5.4-*tp*t p51Learn 3(i;it &
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% Study Bote
formats and stored in dierent lo*ations t-rou.-out an or.anisation
) Find !atterns and trends t-at *ant 6e found &it- data6ases
5 Analse lar.e amounts of -istori*al data Dui*7l
+ Assist mana.ement in ma7in. &ell=informed 6usiness de*isions
Mana.e a -i.- demand for info from man users &it- dierent needs andde*ision=ma7in. stles
" Data -arts p0&
% Study Bote
1 Data mart$
= Smaller %ersion of a data &are-ouse= Used 6 a sin.le de!artment or fun*tion= Fo*us on 6usiness fun*tions for a s!e*i8* user .rou! see a6o%e
2 'ata marts -a%e t-e follo&in. advanta$es o%er data &are-ouses$
= A**ess to data is often faster 6e*ause of t-eir smaller siJe= Res!onse time for users is im!ro%ed= Easier to *reate 6e*ause t-ere smaller and often less *om!le?= (ess e?!ensi%e= Users are tar.eted 6etter9 6e*ause a data mart is desi.ned for a
s!e*i8* de!artment or di%ision
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CH4 *ersonal Le$al t(i!al and Or$anisational Issues of
ISs p0@
1 6is/s Asso!iated wit( Information 'e!(nolo$ies p0
Man of t-e ris7s mentioned -ere *an 6e minimised or !re%ented 6$
% ?(at ou Can Do
1 Installin. OS u!dates re.ularl
2 Usin. anti=%irus and anti=s!&are soft&are
, Usin. e=mail se*urit features
1 ooies p59
% Study Bote
1 Coo/ies are small te?t 8les &it- uniDue I' ta.s t-at are em6edded in a &e6
6ro&ser and sa%ed on t-e users -ard dri%e
2 Sp,0are an# "#0are p6
Spyware stud notes$
% Study Bote
1 Spyware is soft&are t-at se*retl .at-ers info a6out users &-ile t-e 6ro&se
t-e &e6
2 Spyware *an also interfere &it- users *ontrol of t-eir *om!uters 6
installin. additional soft&are and redire*tin. &e6 6ro&sers
, Some s!&are *-an.es *om!uter settin.s9 resultin. in slo& internet
*onne*tions9 *-an.es to default -ome !a.es9 and loss of fun*tions in ot-er
!ro.rams et*"
Adware stud notes$
% Study Bote
1 Adware is a form of s!&are t-at *olle*ts info a6out t-e user &it-out t-e
users *onsent
2 It uses t-is info to dis!la ads in t-e &e6 6ro&ser 6ased on info it *olle*tsfrom t-e users 6ro&sin. !atterns
, In addition to anti%irus soft&are9 installin. an ad=6lo*7in. feature is
re*ommended
3 Phishing p6
% Study Bote
1 *(is(in$ is sendin. fraudulent e=mails t-at seem to *ome from le.itimate
sour*es
2 T-e usuall dire*t e=mail re*i!ients to false &e6sites t-at loo7 li7e t-e real
t-in. for !ur!oses of *a!turin. !ri%ate info e"." 6an7 a**ount num6ers or!ass&ords
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4 ?e,'oggers p6
% Study Bote
1 #eylo$$ers monitor and re*ord 7estro7es and *an 6e soft&are or -ard&are
de%i*es
5 Sni@ng an# Spoong p6
% Study Bote
1 Snin$ is *a!turin. and re*ordin. net&or7 traH* *an 6e used to monitor
net&or7 !erforman*e
2 Spoo>n$ is an attem!t to .ain a**ess to a net&or7 6 !osin. as an
aut-orised user to 8nd sensiti%e info it *an 6e ille.itimate !ro.rams !osin.
as le.itimate ones
6 omp*ter rime an# %ra*# p6
% Study Bote
1 Com!uter fraud is t-e unaut-orised use of *om!uter data for !ersonal .ain
e"." transferrin. mone
2 E?am!les of *om!uter *rimes in*lude$
= 'enial=of=ser%i*e atat*7s= Identit t-eft= Soft&are !ira*= 'istri6utin. *-ild !orno.ra!-= E=mail s!ammin.= :ritin. or s!readin. %iruses= Stealin. 8les for industrial es!iona.e= C-an.in. *om!uter re*ords ille.all= >irus -oa?es
0 *riva!y Issues p"1
% Study Bote
1 T-ere are , NB *on*e!ts re.ardin. internet and networ/ priva!y$
= A**e!ta6le use !oli*ies$ a set of rules s!e*ifin. t-e le.al and et-i*al
use of a sstem and t-e *onseDuen*es of non*om!lian*e= A**ounta6ilit$ refers to issues in%ol%in. 6ot- t-e users and t-e
or.anisations res!onsi6ilit and lia6ilit= Nonre!udiation$ a met-od for 6indin. all in%ol%ed !arties to a *ontra*t
2 uidelines to eliminate or minimise t-e in%asion of priva!y$ study p"&
1 +mai' p63
% Study Bote
1 Spam 3un7 mail is unsoli*ited e=mail sent for ad%ertisin. !ur!oses
2 ase of a!!ess is a *on*ern &-et-er an e=mail is distri6uted t-rou.- t-e
internet or t-rou.- a *om!an net&or7
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2 Data o''ection on the Internet p64
% Study Bote
1 T-ere are 2 *ommon te*-nolo.ies used for data *olle*tion$
= Coo7ies= (o. 8les$ .enerated 6 &e6 ser%er soft&are and re*ord a users a*tions
on a &e6site
0 t(i!al Issues of Information 'e!(nolo$ies p"0
% Study Bote
1 Et-i*s means doin. t-e ri.-t t-in. and its meanin. *an %ar from *ulture to
*ulture and !erson to !erson
2 An e?am!le of a *ode of et-i*s moral .uidelines$
= Contri6ute to so*iet and -uman &ell=6ein.= A%oid -arm to ot-ers= Be -onest and trust&ort-= Be fair and ta7e a*tions not to dis*riminate= #onour !ro!ert ri.-ts9 in*ludin. *o!ri.-ts and !atents=
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% Study Bote
= Co!ri.-t la&s .i%e onl t-e *reator e?*lusi%e ri.-ts meanin. no one
else *an re!rodu*e9 distri6ute9 or !erform t-e &or7 &it-out !ermission= Co!ri.-ts last for t-e aut-ors lifetime L 0 ears and do not need to
6e rene&ed
) T-in.s to 7no& a6out trademar/s and patents$= A trademar/ !rote*ts !rodu*t names and identifin. mar7s e"." lo.os= A patent !rote*ts ne& !ro*esses !atents last 20 ears 1) ears for
desi.n !atents= An or.anisation *an 6ene8t from a !atent in at least , &as$
o
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1 IT an# Aea'th Iss*es p1
% Study Bote
1 :or7 -a6it and &or7 en%ironments *an *ause !-si*al !ro6lems due to$
= Stati* ele*tri*it= InadeDuate %entilation
= /oor li.-tin.= 'r air= Unsuita6le furniture= Too fe& rest 6rea7s
2 #ealt- !ro6lems related to *om!uter eDui!ment in*lude$
= >ision !ro6lems$ fati.ue9 it*-in.9 6lurred %ision= Mus*ulos7eletal !ro6lems$ 6a*7 s!rain and &rist !ain= S7in !ro6lems$ ras-es= Stress=related !ro6lems$ -eada*-es and de!ression
, Er.onomi* fa*tors t-at *an sol%e man of t-ese !ro6lems$
= Fle?i6le or &ireless 7e6oards
= Corre*t li.-tin.= S!e*ial monitors for &or7ers &it- %ision !ro6lems
0 reen Computin$ p.1
% Study Bote
1 reen !omputin$ is *om!utin. t-at !romotes a sustaina6le en%ironment
and *onsumes t-e least amount of ener.
2
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Data Communi!ation t(e Internet 5Commer!e and
lo;al Information Systems p4
CH0 *rote!tin$ Information 6esour!es p.4
1 Computer and Betwor/ Se!urity: )asi! Safe$uards p.0
#a*7ers use a %ariet of tools to 6rea7 into *om!uters$
% Study Bote
1 Sniers
2 /ass&ord *ra*7ers
, Root7its
) ournals$ /-ra*7 and 2+00$ T-e #a*7er uarterl
T!es of -a*7ers !+$
% Study Bote
1 S*ri!t 7iddie
2 Bla*7 -at
, :-ite -at9 a7a @et-i*al -a*7ers
T-ere are , im!ortant as!e*ts of *om!uter and net&or7 se*urit9 *olle*ti%el
referred to as t-e CIA trian.le$
% Study Bote
1 Con8dentialit non=dis*losure of info to anone &-o isnt aut-orised
2 Inte.rit refers to t-e a**ura* of info resour*es &it- an or.anisation as
&ell as identifin. aut-orised users and .rantin. t-em a*ess !ri%ile.es
, A%aila6ilit
T-e -!Cum;er Cu;e !+$
% Study Bote
1 It is re!resented as a , dimensional *u6e2 It de8nes ; *-ara*teristi*s of information se*urit$
= Transmission= Stora.e= /ro*essin.= Con8dentialit= Inte.rit= A%aila6ilit= #uman fa*tors= /oli* and !ra*ti*es= Te*-nolo.
, T-is model in*ludes t-e dierent states in &-i*- information *an e?ist in asstem$
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% Study Bote
= Transa*tion= Stora.e= /ro*essin.
In addition9 a *om!re-ensi%e se*urit sstem must !ro%ide , le%els of se*urit
!$
% Study Bote
1 (e%el 1$ front=end ser%ers e"." e=mail and &e6ser%ers must 6e !rote*ted
a.ainst unaut-orised a**ess
2 (e%el 2$ Ba*7=end sstems must 6e !rote*ted to ensure$
= Con8dentialit= A**ura*= Inte.rit of data
, (e%el ,$ t-e *or!orate net&or7 must 6e !rote*ted a.ainst$= Intrusion= 'enial=of=ser%i*e atta*7s= Unaut-orised a**ess
'(e >rst step in plannin$ a !ompre(ensive se!urity system$ A fault5
tolerant system uses a *om6ination of -ard&are and soft&are for im!ro%in.
relia6ilit it is a &a of ensurin. a%aila6ilit in *ase of a sstem failure"
Some *ommonl used met-ods in*lude !$
% Study Bote
1 Uninterru!ta6le !o&er su!!l U/S ser%es 2 *ru*ial tas7s$
= It ser%es as a !o&er sour*e to *ontinue runnin. t-e ser%er usuall for
a s-ort !eriod= Safel s-uts do&n t-e ser%er
2 Redundant arra of inde!endent dis7s RAI'$
= Colle*tion of dis7 dri%es used to store data in multi!le !la*es= Stores a %alue *alled a *-e*7sum t-at is used to %erif t-at data -as
6een stored or transmitted &it-out error
, Mirror dis7s$= Uses 2 dis7s *ontainin. t-e same data= It is a le%el=1 RAI' sstem
2 Se!urity '(reats: An Overview p..
2.1 Intentiona' Threats p
Intentional *om!uter and net&or7 t-reats in*lude$
% '(reat
1 >iruses2 :orms
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% '(reat
, Tro3an !ro.rams
) (o.i* 6om6s
5 Ba*7doors
+ Blended t-reats e"." &orm laun*-ed 6 a Tro3an
Root7its4 'enial=of=ser%i*e atta*7s
; So*ial en.ineerin.
2"1"1 >iruses !4
% Study Bote
1 Consists of a self=!ro!a.atin. !ro.ram *ode t-ats tri..ered 6 a s!e*i8*
time or e%ent9 t-e %irus atta*-es itself to ot-er 8les &-en t-e !ro.ram or OS
*ontainin. t-e %irus is used
2 Indi*ations t-at a *om!uter mi.-t 6e infe*ted 6 a %irus$
= Some !ro.rams -a%e suddenl in*reased in siJe= Files -a%e 6een *orru!ted9 or ou *ant o!en some 8les= #ard dis7 free s!a*e is redu*ed drasti*all= T-e 7e6oard lo*7s u!9 or t-e s*reen freeJes= A%aila6le memor di!s do&n more t-an usual= 'is7 a**ess is slo&= Com!uter tas7s ta7e lon.er t-an usual to start= Une?!e*ted dis7 a*ti%it= Unfamiliar messa.es on t-e s*reen
2"1"2 :orms !;% Study Bote
1 Tra%els from *om!uter to *om!uter 6ut doesnt usuall erase data
2 Unli7e a %irus9 it is an inde!endent !ro.ram t-at *an s!read itself &it-out
-a%in. to 6e atta*-ed to a -ost !ro.ram
, Eats u! resour*es9 e%entuall 6rin.in. a *om!uter or a net&or7 to a -alt
2"1", Tro3an /ro.rams !;
% Study Bote
1 Contains *ode intended to disru!t a *om!uter9 net&or79 or &e6site and is
usuall -idden inside a !o!ular !ro.ram
2 T-e dont re!li*ate t-emsel%es as %iruses and &orms do
2"1") (o.i* Bom6s !;
% Study Bote
1 T!e of Tro3an !ro.ram used to release a %irus9 &orm9 or ot-er destru*ti%e
*ode
2 Tri..ered at a *ertain time e"." 6irt-da of a famous !erson or 6 a s!e*i8*
e%ent e"." !ressin. enter
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2"1"5 Ba*7doors !;
% Study Bote
1 Also *alled a @tra!door
2 /ro.rammin. routine 6uilt into a sstem 6 its desi.ner or !ro.rammer t-at
ena6les t-e desi.ner or !ro.rammer to 6!ass se*urit and snea7 6a*7 into
t-e sstem later to a**ess !ro.rams or 8les
2"1"+ Blended T-reats !;
% Study Bote
1 Se*urit t-reat t-at *om6ines t-e *-ara*teristi*s of *om!uter %iruses9 &orms9
and ot-er mali*ious *odes &it- %ulnera6ilities found on !u6li* and !ri%ate
net&or7s
2 Blended t-reats sear*- for %ulnera6ilities on *om!uter net&or7s and t-en
ta7e ad%anta.e 6 em6eddin. mali*ious *odes in t-e ser%ers #TM( 8les or
6 sendin. unaut-orised e=mails from *om!romised ser%ers &it- a &ormatta*-ment
2"1" 'enial=of=Ser%i*e Atta*7s 'oS !40
% Study Bote
1 Floods a net&or7 or ser%er &it- ser%i*e reDuests to !re%ent le.itimate users
a**ess to t-e sstem
2 Usuall tar.et internet ser%ers$ &e69 FT/9 or mail ser%ers alt-ou.- an
sstem *onne*ted to t-e internet runnin. TC/ ser%i*es is su63e*t to atta*7
2"1"4 So*ial En.ineerin. !40
% Study Bote
1 Means usin. !eo!le s7ills su*- as 6ein. a .ood listener and assumin. a
friendl9 unt-reatenin. air to tri*7 ot-ers into re%ealin. !ri%ate info
2 It ta7es ad%anta.e of t-e -uman element of se*urit sstems
, Common te*-niDues in*lude$
= 'um!ster di%in.= S-oulder sur8n.
& Se!urity -easures and nfor!ement: An Overview p@1
Or.anisations *an ta7e man ste!s to .uard a.ainst t-reats$
% Study Bote
1 Biometri* se*urit measures
2 Non=6iometri* se*urit measures
, /-si*al se*urit measures
) A**ess *ontrols
5 >irtual !ri%ate net&or7s >/N
+ 'ata en*r!tion
E=*ommer*e transa*tion se*urit measures4 Com!uter Emer.en* Res!onse Team CERT
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3.1 )iometric Sec*rit, &eas*res p81
% Study Bote
1 Use a !-siolo.i*al element to en-an*e se*urit measures
2 It is uniDue to a !erson and *ant 6e stolen9 lost9 *o!ied9 or !assed on toot-ers
, Biometri* se*urit in*ludes$
= Fa*ial re*o.nition s-a!e9 !attern9 and !ositionin.= Fin.er!rints= #and .eometr *om!are len.t- of ea*- 8n.er9 translu*en*e of
8n.er ti!s9 &e66in. 6et&een 8n.ers a.ainst stored data
) Iris analsis
5 /alm !rints !alm reader uses near infrared li.-t to *a!ture a users %ein
!attern
+ Retinal s*annin.
Si.nature analsis !en !ressure9 s!eed9 len.t- of time to si.n4 >ein analsis in &rist and 6a*7 of t-e -and 6ut no dire*t *onta*t is made
; >oi*e re*o.nition translate &ords into di.ital !atterns9 re*orded and
e?amined for tone and !it*- and *an &or7 o%er lon. distan*es e"." ordinar
tele!-one
1
0
'ra&6a*7s in*lude$
= #i.- *osts= Users relu*tan*e= Com!le? installation
3.2 /onbiometric Sec*rit, &eas*res p81
T-e , main non=6iometri* se*urit measures are$
% Study Bote
1 Call6a*7 modems
2 Fire&alls
, Intrusion dete*tion sstems
,"2"1 Call6a*7 Modems !42
% Study Bote
1 >eri8es &-et-er a users a**ess is %alid 6 lo..in. t-e user o and t-e
*allin. t-e user 6a*7
2 Useful in or.anisations &it- man em!loees &-o &or7 o=site and &-o need
to *onne*t to t-e net&or7 from remote lo*ations
,"2"2 Fire&alls !42
% Study Bote
1 Com6ination of -ard&are and soft&are t-at a*ts as a 8lter or 6arrier 6et&eena !ri%ate net&or7 and e?ternal *om!uters or net&or7s9 in*ludin. t-e internet
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% Study Bote
2 A 8re&all *an e?amine data !assin. into or out of a !ri%ate net&or7 and
de*ide &-et-er to allo& t-e transmission 6ased on$
= Users I'= T-e transmissions ori.in and destination
= T-e transmissions *ontents, Info 6ein. transmitted is stored in a !a*7et9 after e?aminin. t-e !a*7et9 a
8re&all *an ta7e one of t-e follo&in. a*tions$
= Re3e*t t-e in*omin. !a*7et= Send a &arnin. to t-e net&or7 administrator= Send a messa.e to t-e !a*7ets sender t-at t-e attem!t failed= Allo& t-e !a*7et to enter or lea%e t-e !ri%ate net&or7
) T-e main t!es of 8re&alls are$
= /a*7et=8lterin. 8re&alls= A!!li*ation=8lterin. 8re&alls= /ro? ser%ers
Packet-fltering frewalls work like this p83:
% Study Bote
1 /a*7et=8lterin. 8re&alls *ontrol data traH* 6 *on8.urin. a router to
e?amine !a*7ets !assin. into and out of t-e net&or7
2 T-e router e?amines t-e follo&in. info in a !a*7et$
= Sour*e I/ address and !ort= 'estination I/ address and !ort= /roto*ol used
, Based on t-is info9 rules *alled @!a*7et 8lters determine &-et-er a !a*7et is
a**e!ted9 re3e*ted9 or dro!!ed
) For e?am!le$
= A !a*7et 8lter *an 6e set u! to den !a*7ets from s!e*i8* I/ addresses= A !a*7et=8lterin. 8re&all informs senders if !a*7ets are re3e*ted 6ut
does not-in. if !a*7ets are dro!!ed= Senders -a%e to &ait until t-eir reDuests time out to learn t-at t-e
!a*7ets t-e sent &erent re*ei%ed
5 T-ese 8re&alls re*ord all in*omin. *onne*tions9 and !a*7ets t-at are re3e*ted
mi.-t 6e a &arnin. si.n of unaut-orised attem!ts
+ /a*7et=8lterin. 8re&alls are ineH*ient 6e*ause$
= T-e -a%e to e?amine !a*7ets one=6=one= T-e mi.-t 6e diH*ult to install= T-e *ant usuall re*ord e%er a*tion ta7in. !la*e at t-e 8re&all
Application-fltering frewalls work like this p83:
% Study Bote
1 A!!li*ation=8lterin. 8re&alls are .enerall more se*ure and Ge?i6le t-an
!a*7et=8lterin. 8re&alls 6ut t-e are more e?!ensi%e
2 T!i*all9 t-e are soft&are t-at is installed on a -ost *om!uter a dedi*ated
&or7station or ser%er to *ontrol use of net&or7 a!!li*ations9 su*- as$
= E=mail= Telnet
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% Study Bote
= FT/
, T-ese 8re&alls monitor t-e follo&in.$
= :-i*- a!!li*ations &ere reDuested= T-e time at &-i*- a!!li*ation reDuests ta7e !la*e
) A!!li*ation=8lterin. 8re&alls 8lter %iruses and lo. a*tions more ee*ti%elt-an !a*7et=8lterin. 8re&alls t-is -el!s net&or7 admins s!ot !otential
se*urit 6rea*-es
5 T-ese 8re&alls are often slo&er t-an ot-er 8re&alls &-i*- *an ae*t net&or7
!erforman*e t-is is due to all t-e a!!li*ation 8lterin. t-at t-e do
Proxy servers work like this p83:
% Study Bote
1 A !ro? ser%er is soft&are t-at a*ts as an intermediar 6et&een t&o sstems
6et&een net&or7 users and t-e internet
2 Its often used to !rote*t t-e net&or7 a.ainst unaut-orised a**ess from t-e
outside 6 -idin. t-e net&or7 addresses of internal sstems
, It *an also 6e used as a 8re&all t-at s*ans for mal&are and %iruses9 s!eeds
u! net&or7 traH*9 or ta7es some load o internal ser%ers &-i*- 8re&alls
*ant do it *an also 6lo*7 reDuests from *ertain ser%ers
) Learn 3(i;it 0
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3.3 Ph,sica' Sec*rit, &eas*res p84
% Study Bote
1 /-si*al se*urit measures !rimaril *ontrol a**ess to *om!uters and
net&or7s and in*lude de%i*es for se*urin. *om!uters and !eri!-erals fromt-eft
2 Common !-si*al se*urit measures$
= Ca6le s-ieldin. !rote*tion from ele*troma.neti* interferen*e EMI= Corner 6olts= Ele*troni* tra*7ers se*ured to t-e *om!uter at t-e !o&er outlet= Identi8*ation I' 6ad.es *-e*7ed a.ainst a list of aut-orised
!ersonnel= /ro?imit=release door o!eners radio transmitters= Room s-ieldin. non=*ondu*ti%e material= Steel en*asements 8t o%er entire *om!uter and *an 6e lo*7ed
3.4 "ccess ontro's p86
% Study Bote
1 A**ess *ontrols are desi.ned to !rote*t sstems from unaut-orised a**ess in
order to !reser%e data inte.rit
2 T&o &idel used a**ess *ontrols are$
= Terminal Resour*e Se*urit= /ass&ords
,
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% Study Bote
= 'edi*ated Inte.rated Ser%i*es 'i.ital Net&or7 IS'N lines= T1 lines
Learn 3(i;it 0
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3. +ommerce Transaction Sec*rit, &eas*res p89
In e=*ommer*e , fa*tors are *riti*al for se*urit$
% Study Bote
1 Aut-enti*ation
2 Con8rmation, Non=re!udiation of ori.in and re*ei!t
) Ot-er fa*tors$
= Inte.rit
3.8 omp*ter +mergenc, esponse Team =+T> p89
% Study Bote
1 Currentl CERT fo*uses on$
= Se*urit 6rea*-es= 'oS atta*7s
CERT oers .uidelines on -andlin. and !re%entin. t-ese in*idents
4 uidelines for a Compre(ensive Se!urity System p@
T-e follo&in. ste!s s-ould 6e *onsidered &-en de%elo!in. a *om!re-ensi%e
se*urit !lan$
% Step
1 Set u! a se*urit *ommittee &it- re!resentati%es from all de!artments as
&ell as u!!er mana.ement t-e *ommittees res!onsi6ilities in*lude$
= 'e%elo!in. *lear9 detailed se*urit !oli* and !ro*edures= /ro%idin. se*urit trainin. and se*urit a&areness for 7e de*ision
ma7ers and *om!uter users= /eriodi*all assessin. t-e se*urit !oli*s ee*ti%eness= 'e%elo!in. and audit !ro*edure for lo.ins and sstem use= O%erseein. enfor*ement of t-e se*urit !oli*= 'esi.nin. an audit trail !ro*edure for in*omin. and out.oin. data
2 /ost t-e se*urit !oli* in a %isi6le !la*e
, Raise em!loees a&areness of se*urit !ro6lems
) Re%o7e terminated em!loees !ass&ords and I' 6ad.es
5 ee! sensiti%e data9 soft&are9 and !rintouts lo*7ed u! in se*ure lo*ations
E?it !ro.rams and sstems !rom!tl9 and ne%er lea%e lo..ed=on
&or7stations unattended
+ (imit *om!uter a**ess to aut-orised !ersonnel onl
Install anti=%irus !ro.rams and ma7e sure t-ere u!dated automati*all
4 Install onl li*enses soft&are 6ou.-t from a re!uta6le dealer
; Install 8re&alls and intruder dete*tion sstems and *onsider 6iometri*
se*urit measures
4.1 )*siness ontin*it, P'anning =)P> p91
% Study Botes
1 Outlines !ro*edures for 7ee!in. an or.anisation o!erational in t-e *ase of natural disaster or net&or7 atta*7 or intrusion
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% Study Botes
2 A disaster re!overy !lan lists t-e tas7s t-at must 6e !erformed to restore
data and eDui!ment as &ell as t-e ste!s to !re!are for disaster9 su*- as$
= Ba*7 u! all 8les= Re%ie& se*urit and 8re standards for *om!uter fa*ilities !eriodi*all
= Re%ie& info from CERT and ot-er se*urit a.en*ies !eriodi*all= Ma7e sure sta mem6ers -a%e 6een trained and are a&are of t-e
*onseDuen*es of !ossi6le disasters and ste!s to redu*e t-e ee*ts of
disasters= Test t-e 'R !lan &it- trial data= Identif %endors of all soft&are and -ard&are used in t-e or.anisation
and ma7e sure t-eir *onta*t details are u!=to=date= 'o*ument all *-an.es made to -ard&are and soft&are=
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CH" Data Communi!ation: Deliverin$ Information Anyw(ere
and Anytime p4
1 De>nin$ Data Communi!ation p0
% Study Bote1 'e8nition$ T-e ele*troni* transfer of data from one lo*ation to anot-er$ a data
*ommuni*ation sstem ena6les an information sstem to deli%er information
2 A data *ommuni*ation sstem *an also im!ro%e t-e Ge?i6ilit of data
*olle*tion and transmission$ it is t-e 6asis of %irtual or.anisations and e=
*olla6oration
, :- mana.ers need to 7no& a6out data *ommuni*ation$
= En-an*e de*ision ma7ers eH*ien* and ee*ti%eness$ *olla6oration
and *oordination= Im!ro%e !rodu*ti%it$ email9 net&or7s
2 )asi! Components of a Data Communi!ation System p.
% Study Bote
1 A data *ommuni*ation sstem in*ludes t-e follo&in. *om!onents$
= Sender and re*ei%er de%i*es= Modems and routers= Communi*ation medium *-annel
2 Basi* *on*e!ts !;$
= )andwidt($ t-e amount of data t-at *an 6e transferred from one
!oint to anot-er in a *ertain time !eriod9 usuall one se*ond" E?!ress
as 6!s9 6!s9 M6!s9
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% Devi!e
5 Mini *om!uters9 mainframes9 or su!er*om!uters
+ Smart!-ones9 mo6ile !-ones9 M/, !laers9 /'As9 and .ame *onsoles
2.2 &o#ems =short for Cmo#*'ator#emo#*'ator> p9Not an
2.3 omm*nication &e#ia = or Cchanne's> p98
Communi*ation media *onne*t sender and re*ei%er de%i*es t-e *an 6e
*ondu*ted &ired or radiated &ireless"
% Study Bote
1 Condu*ted media= !ro%ide a !-si*al !at- alon. &-i*- si.nals are
transmitted$= T&isted !air *a6le$ t&isted *o!!er lines used in t-e tele!-one net&or7
and *ommuni*ation &it-in 6uildin.s= Coa?ial *a6le$ 6ot- data and %oi*e transmissions used for lon.
distan*e tele!-one transmissions and (ANs= Fi6re o!ti* *a6le$ .lass tu6es surrounded 6 *on*entri* laers of .lass
*alled @*laddin. to form a li.-t !at- t-rou.- &ire *a6les
2 Radiated media use an antenna for transmittin. data t-rou.- air or &ater
6road*ast radio9 mi*ro&a%e and satellite use line=of=si.-t
& *ro!essin$ Con>$urations pCentralised9 de*entralised9 and distri6uted$
% Study Bote
1 Centralised !ro*essin. = all !ro*essin. is done at one *entral *om!uter not
in use mu*- anmore
2 'e*entralised !ro*essin. ea*- de!artment -as its o&n *om!uter *alled an
@or.anisational unit
, 'istri6uted !ro*essin. maintains *entralised *ontrol and de*entralises
o!erations !ro*essin. !o&er is distri6uted amon. se%eral lo*ations" T-e
ad%anta.es in*lude$
= A**essin. unused !ro*essin. !o&er is !ossi6le= Modular desi.n means *om!uter !o&er *an 6e added 6ased on need= 'istan*e and lo*ation arent limitin.= Com!ati6le &it- or.anisational .ro&t- 6e*ause &or7stations *an 6e
added= Fault toleran*e im!ro%ed 6e*ause of a%aila6ilit of redundant
resour*es= Relia6ilit is im!ro%ed 6e*ause sstem failures *an 6e limited to one
site= T-e sstem is more res!onsi%e to user needs
T-e disad%anta.es in*lude$
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% Study Bote
= 'e!enden*e on *ommuni*ation te*-nolo.= In*om!ati6ilit 6et&een eDui!ment= More *-allen.in. net&or7 mana.ement
3.4 -pen S,stems Interconnection &o#e' =-SI> p1
T-e OSI is a se%en=laer ar*-ite*ture for de8nin. -o& data is transmitted from
*om!uter to *om!uter in a net&or79 from t-e !-si*al *onne*tion to t-e net&or7
to t-e a!!li*ations t-at users run" OSI also standardises intera*tions 6et&een
net&or7 *om!uters e?*-an.in. information" Ea*- laer in t-e ar*-ite*ture
!erforms a s!e*i8* tas7$
% Study Bote
1 Appli!ation layer t-e &indo& t-rou.- &-i*- a!!li*ations a**ess net&or7
ser%i*es e"." 8le transfers9 data6ase a**ess9 and email
2 *resentation layer res!onsi6le for formattin. messa.e !a*7ets, Session layer esta6lis-es a *ommuni*ation session 6et&een *om!uters
) 'ransport layer
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% Study Bote
2 Et-ernet *a6le used to *onne*t *om!uters9 -u6s9 s&it*-es9 routers to a
net&or7
4.2 7"/s p11A :AN *an s!an se%eral *ities or *ountries and is usuall o&ned 6 se%eral
dierent !arties" T-e data transfer s!eed de!ends on t-e s!eed of its
inter*onne*tions9 or @lin7s and *an %ar from 24"46!s to 155M6!s
4.3&etropo'itan "rea /et0ors =&"/s> p11
A MAN is desi.ned to -andle data *ommuni*ation for multi!le or.anisations in a
*it andor near6 *ities" T-e data transfer s!eed %aries from ,5M6!s to
155M6!s"
0 Betwor/ 'opolo$ies p182
A net&or7 to!olo. re!resents a net&or7s !-si*al laout9 in*l" t-e arran.ementof *om!uters and *a6les"
5.1 Star topo'og, p12
% Star 'opolo$y Study Bote
1 Consists of a *entral *om!uter ser%er and a series of nodes &or7stations or
!eri!-eral de%i*es
2 T-e -ost *om!uter su!!lies t-e main !ro*essin. !o&er
, Ad%anta.es in*lude$
= Ca6le laouts are eas to modif= Centralised *ontrol ma7es dete*tin. !ro6lems easier= Nodes *an 6e added to t-e net&or7 easil= More ee*ti%e at -andlin. -ea% 6ut s-ort 6ursts of traH*
) 'isad%anta.es in*lude$
= Central -ost means a sin.le !oint of failure= Man *a6les reDuired &-i*- in*reases *ost
5.2 ing Topo'og, p13
% 6in$ 'opolo$y Study Bote
1 No -ost *om!uter is reDuired9 ea*- *om!uter mana.es its o&n *onne*ti%it
2 Com!uters and de%i*es are arran.ed in a *ir*le so t-at ea*- node is*onne*ted to t&o ot-er nodes$ u!stream and do&nstream nei.-6our &it-
transmission in one dire*tion
, Ad%anta.es in*lude$
= (ess *a6le t-at a star to!olo.
) 'isad%anta.es in*lude$
= If an lin7 6et&een nodes is se%ered9 t-e entire net&or7 is ae*ted= 'ia.nosin. !ro6lems and modifin. t-e net&or7 are more diH*ult t-an
&it- a star to!olo.
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5.3 )*s Topo'og, =or C'inear b*s> p13
% )us 'opolo$y Study Bote
1 Conne*ts nodes alon. a net&or7 se.ment9 6ut t-e ends of t-e *a6le arent
*onne*ted9 as t-e are in a rin. to!olo. a -ard&are de%i*e *alled a
terminator is used at ea*- end of t-e *a6le to a6sor6 t-e si.nal
2 Common s!eeds in a 6us to!olo. are$ 19 2"59 59 109 100M6!s9 1 p13
% Hierar!(i!al 'opolo$y Study Bote
1 Com6ines *om!uters &it- dierent !ro*essin. stren.t-s in dierent
or.anisational le%els e"." mainframe
2 Uses *ontrollers and multi!le?ers -ard&are de%i*e t-at allo&s se%eral nodes
to s-are one *ommuni*ation *-annel
, Ad%anta.es in*lude$
= er relia6le 6ut *ostl and diH*ult to maintain and e?!and
" -aor Betwor/in$ Con!epts p184
6.1 Protoco's p14
% *roto!ols Study Botes
1 Met-ods and rules t-at ele*troni* de%i*es use to e?*-an.e information
2 Some !roto*ols deal &it- -ard&are *onne*tions9 ot-ers *ontrol data
transmission and 8le transfers
, /roto*ols s!e*if t-e format of messa.e !a*7ets sent 6et&een *om!uters
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6.2 Transmission ontro' Protoco'Internet Protoco' =TPIP> p14
% 'C*I* Study Botes
1 TC/I/ is an industr=standard suite of *ommuni*ation !roto*ols it ena6les
intero!era6ilit i"e" allo&s lin7in. of de%i*es runnin. on man dierent
!latforms
2 TC/$
= O!erates at OSIs trans!ort laer= /rimar fun*tion$ esta6lis- lin7 6et&een -osts9 ensure messa.e
inte.rit9 seDuen*in.9 and a*7no&led.in. !a*7et deli%er9 and
re.ulatin. data Go& 6et&een sour*e and destination nodes
, I/ $
= O!erates at OSIs net&or7 laer= Res!onsi6le for !a*7et for&ardin.= 'i%ided into 2 !arts$ net&or7 address and node address
6.3 o*ting p15
% 6outin$ Study Botes
1 /a*7et s&it*-in. a net&or7 *ommuni*ation met-od t-at di%ides data into
small !a*7ets and transmits t-em to an address9 &-ere t-e are reassem6led
2 A !a*7et *olle*tion of 6inar di.its in*l" messa.e data and *ontrol
*-ara*ters for formattin. and transmittin.9 sent from *om!uter to *om!uter
o%er a net&or7
, T-e !at- or route t-at data ta7es on a net&or7 is determined 6 t-e t!e of
net&or7 and t-e soft&are used to transmit data t-e !ro*ess of de*idin.
&-i*- !at- t-at data ta7es is *alled routin$
) T-e de*ision a6out &-i*- route to follo& is done in one of t&o &as$
= At a *entral lo*ation !entralised routin$ usin. a routin$ ta;lelists nodes on a net&or7 and t-e !at- to ea*- node9 alon. &it-
alternate routes and t-e s!eed of e?istin. routes" One node net&or7
routin. mana.er is in *-ar.e of sele*tin. t-e !at- for all !a*7ets= Distri;uted routin$ relies on ea*- node to *al*ulate t-e 6est
!ossi6le route" Ea*- node *ontains its o&n routin. ta6le &it- *urrent
information on t-e status of ad3a*ent nodes so t-at t-e 6est !ossi6le
route *an 6e follo&ed
6.4 o*ters p16
% 6outers Study Botes
1 A router is a net&or7 *onne*tion de%i*e *ontainin. soft&are t-at *onne*ts
net&or7 sstems and *ontrols traH* Go& 6et&een t-em
2 Routers$
= O!erate at t-e OSI net&or7 laer and -andle routin. !a*7ets on a
net&or7= Can sele*t t-e 6est !ossi6le !at- for !a*7ets 6ased on distan*e or *ost= Can !re%ent net&or7 3ams t-at dela !a*7et deli%er and -andle
!a*7ets of dierent siJes= Can 6e used for se.mentin.isolate a !ortion of t-e (AN from t-e rest
of t-e net&or7, T-ere are 2 t!es of routers = stati* and dnami*$
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% 6outers Study Botes
= Stati! router$ reDuires t-e net&or7 routin. mana.er to .i%e it
information a6out &-i*- addresses are on &-i*- net&or7= Dynami! router$ *an 6uild ta6les t-at identif addresses on ea*-
net&or7
6.5 'ientSer!er &o#e' p16
Study e3(i;its on p18.518@
% ClientServer Study Botes
1 In t-e most 6asi* *lientser%er *on8.9 t-e follo&in. e%ents usuall ta7e !la*e$
1" T-e user runs *lient soft&are to *reate a Duer2" T-e *lient a**e!ts t-e reDuest and formats it so t-at t-e ser%er *an
understand it," T-e *lient sends t-e reDuest to t-e ser%er o%er t-e net&or7
)" T-e ser%er re*ei%es and !ro*esses t-e Duer5" T-e results are sent to t-e *lient+" T-e results are formatted and dis!laed to t-e user in an
understanda6le format
2 T-e t-ree le%els of lo.i*$
= /resentation lo.i* -o& data is returned to t-e *lient e"."
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% ?ireless and -o;ile Betwor/s Study Botes
= (imited t-rou.-!ut similar to 6and&idt-= (imited ran.e= In=6uildin. !enetration !ro6lems= >ulnera6ilit to freDuen* noise e"." t-understorms and li.-tnin.
= Se*urit e"." sniers
.1 7ire'ess Techno'ogies p19
:(ANs and ::ANs$ study ta;le "
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% ?ireless Se!urity Study Botes
users I' and !ass&ord
) :/A :i=Fi /rote*ted A**ess *om6ines stron.est features of :E/ and EA/$
7es are 8?ed as in :E/9 or dnami*all *-an.ed as in EA/
5 :/A2 uses EA/ to o6tain a master 7e !112
Conver$en!e of Eoi!e Eideo and Data p112
In data *ommuni*ation9 *on%er.en*e refers to inte.ratin. %oi*e9 %ideo9 and data
so t-at multimedia information *an 6e used for de*ision ma7in." Common
a!!li*ations of *on%er.en*e in*lude$
% Conver$en!e Study Botes
1 E=*ommer*e
2 Entertainment e"." %ideos on demand
, In*reased a%aila6ilit and aorda6ilit of %ideo and *om!utin. *onferen*in.
) Consumer !rodu*ts and ser%i*es9 su*- as %irtual *lassrooms9 tele*ommutin.9and %irtual realit
5 Read more on tele!resen*e""
=
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CH. '(e Internet Intranets and 3tranets p11@
1 '(e Internet and t(e ?orld ?ide ?e; p11
% '(e Internet and ??? Study Botes
1 = T-e internet is a net&or7 of net&or7s" It started in 1;+; as a US'e!artment of 'efen*e !ro3e*t *alled Advan!ed 6esear!( *roe!ts
A$en!y Betwor/ AR/ANET= AR/ANET e%ol%ed into t-e Bational S!ien!e Foundation Betwor/
NSFNET in 1;4 &-i*- is *onsidered t-e 8rst internet 6a*76one= T-e internet 6a*76one is a foundation net&or7 lin7ed &it- 86re=o!ti*
*a6les and made u! of man inter*onne*ted -i.-=*a!a*it data routers
2 = T-e ::: or @t-e :e6 *-an.ed t-e internet in 1;4; 6 introdu*in. a
er -i.-=s!eed 'S( >'S( u!do&nstream u! to 100M6!s
) T1 and T, lines 2) simultaneous *-annels at 1"5))M6!s or 2"0)4M6!s !12,
2 Bavi$ation 'ools Sear!( n$ines and Dire!tories p12&
T-e , *ate.ories of tool used to .et around t-e internet$
% Internet Cate$ory Study Botes
1 Na%i.ation tools2 Sear*- en.ines
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% Internet Cate$ory Study Botes
, 'ire*tories inde?es of info 6ased on 7e&ords in do*uments
2.1 /a!igation Too's p123
na
2.2 Search +ngines an# Directories p124
Sear*- en.ines follo& t-is t-ree=ste! !ro*ess$
% Sear!( n$ine Study Botes
1 Cra&lin. t-e &e6 *ra&lers9 s!iders9 6ots
2 Inde?in. ser%er farms inde? data *omin. in from *ra&lers 6 usin.
7e&ords for retrie%al !ur!oses
, T-e sear*- !ro*ess t-e inde? is used to loo7 u! t-e term
'ire*tories$
% Dire!tory Study Botes
1 'ire*tories or.anise info into *ate.ories t-ere are 2 t!es of *ate.ories$
automated or *ra&ler=6ased and -uman=!o&ered dire*tor
2 Automated *reates inde?es of sear*- terms and *olle*ts t-ese terms
automati*all 6 usin. *ra&lers
, #uman=!o&ered manual su6mission of 7e&ords i"e" relies on users to
su!!l t-e data
& Internet Servi!es p120
3.1 +mai' p125
na
3.2 /e0sgro*ps an# Disc*ssion ro*ps p125
% Bews$roup and Dis!ussion roup Study Botes
1 'is*ussion .rou! e?*-an.in. o!inions and ideas on a s!e*i8* to!i*9 usuall
te*-ni*al
2 Ne&s.rou! more .eneral in nature
3.3 Instant &essaging p125
IRC and IM"
3.4 Internet Te'ephon, p126
Ad%anta.es of >OI/ !12+$
% Advanta$es of EOI*
1 Cost sa%in.s
2 Users dont e?!erien*e 6us lines
, >oi*emails *an 6e re*ei%ed on t-e *om!uter) Users *an s*reen *allers e%en if *aller -as *aller I' 6lo*7ed
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% Advanta$es of EOI*
5 Users *an -a%e *alls for&arded from an&-ere in t-e &orld
+ Users *an dire*t *alls to t-e *orre*t de!artments and ta7e automated orders
4 ?e; Appli!ations p12"Refer !12+ for list of industries"
0 Intranets +or G!orporate portals, p1&8
% Intranet Study Botes
1 An intranet is a net&or7 &it-in an or.anisation t-at uses internet !roto*ols
and te*-nolo.ies su*- as TC/I/9 FT/9 SMT/ and ot-ers for *olle*tin.9 storin.
and disseminatin. useful info t-at su!!orts 6usiness a*ti%ities su*- as sales9
*ustomer ser%i*e9 #R9 mar7etin. et*"
5.1 The Internet !s Intranets p131Study 'a;le .
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.1 )'ogs p134
na
.2 7iis p134
na
.3 Socia' net0oring sites p135
na
.4 SS %ee#s p135
Uses QM( format a su6set of S
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CH@ 5Commer!e p148
1 De>nin$ 5Commer!e p148
E=*ommer*e is !art of e=6usiness t-e are not t-e same t-in." E=*ommer*e is
6uin. and sellin. .oods and ser%i*es o%er t-e internet"
1.1 The Ba'*e hain an# +ommerce p142
% Ealue C(ain and 5Commer!e Study Botes
1 Mi*-ael /orter introdu*ed t-e %alue *-ain *on*e!t in 1;45
2 T-e %alue *-ain *on*e!t *onsists of a series of a*ti%ities desi.ned to meet
6usiness needs 6 addin. %alue or *ost in ea*- !-ase of t-e !ro*ess
, T-e %alue *-ain is a6out understandin. &-at as!e*ts of an or.anisations
6usiness add %alue for *ustomers and t-en ma?imisin. t-ose as!e*ts
) Study 3(i;it @
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% Advanta$es of 5Commer!e
0
1
1
Redu*in. admin and transa*tion *osts
'isad%anta.es of e=*ommer*e$
% Disadvanta$es of 5Commer!e
1 Band&idt- *a!a*it !ro6lems
2 Se*urit issues
, A**essi6ilit
) A**e!tan*e
1.4 +ommerce )*siness &o#e's p144
% 5Commer!e )usiness -odel1 Mer*-ant transfers t-e old retail model to t-e e=*ommer*e &orld e"."
AmaJon"*om
2 Bro7era.e 6rin.s sellers and 6uers to.et-er on t-e &e6 and *olle*ts
*ommission on transa*tions e"." e6a"*om
, Ad%ertisin. e"."
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2.5 o!ernment an# /on)*siness +ommerce p14
% overnment and Bon5)usiness +e5$ov, Study Botes
1
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% )uyer5Side -ar/etpla!e Study Botes
sellers to 6id on announ*ed !rodu*ts or RFs
2 Ad%anta.es for sellers in*lude$
= Condu*t sales transa*tions= Automate t-e order mana.ement !ro*ess
= Condu*t !ost=sales analsis= Automate t-e ful8lment fun*tion= Im!ro%e understandin. of 6uin. 6e-a%iours= /ro%ide an alternati%e sales *-annel= Redu*e order !la*ement and deli%er time
4.1.3 Thir#Part, +:change &aretp'ace p15
% '(ird5*arty 3!(an$e -ar/etpla!e Study Botes
1 Controlled 6 a t-ird !art9 t-e mar7et!la*e .enerates re%enue from t-e fees
*-ar.ed for mat*-in. 6uers and sellers
2 >erti*al mar7et *on*entrates on a s!e*i8* industr or mar7et e"." 6eef anddair
, #oriJontal mar7et *on*entrates on a s!e*i8* fun*tion or 6usiness !ro*ess
and automates it for dierent industries e"." em!loee 6ene8ts admin
4
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% ?e; -ar/etin$ Study Botes
2 Cost !er *li*7 C/C
, Cli*7=t-rou.- rate CTR
) S!ot leasin.
6.3 Search +ngine -ptimisation =S+-> p154
e&ords9 !a.e title9 in6ound lin7s"
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CH lo;al Information Systems p10@
1 ?(y o lo;al *10
na
2 lo;al Information Systems: An Overview p1"1
% IS Study Botes
1 An information sstem t-at &or7s a*ross national 6orders9 fa*ilitates
*ommuni*ation 6et&een # and su6sidiaries in ot-er *ountries and
in*or!orates all t-e te*-nolo.ies and a!!li*ations found in a t!i*al IS to
store9 mani!ulate and transmit data a*ross *ultural and .eo.ra!-i*al
6oundaries"
2 A
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% IS Study Botes
!ro%ides$
= O!erational= Ta*ti*al= Strate.i*
) O!erational reDuirements of a
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% -ultinational Study Botes
2 Su6sidiaries o!erate autonomousl 6ut re!ort to t-e !arent *om!an
re.ularl
3.2 'oba' Str*ct*re =or Cfranchiser> p166% lo;al Stru!ture Study Botes
1 #i.-l *entralised information sstems study 3(i;it
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4.1
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/-ase 5 = Maintenan*e
/-ase ) = Im!lementation
/-ase , = 'esi.n
/-ase 2 = ReDuirements .at-erin. and analsis
/-ase 1 = /lannin.
Identif !otentialsstems
Condu*t!reliminaranalsis of
reDuirementsand de8ne t-e
!ro6lem
Condu*tfeasi6ilit studies
Ma7e .o and no=.o de*isions
CH18 )uildin$ Su!!essful Information Systems p1.4
1 Systems Development Life Cy!le +SDLC,: An Overview p1.0
Study 3(i;it 18
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2.2.1 +conomic %easibi'it, p19
% !onomi! Feasi;ility Study Botes
1 Assesses a sstems *osts and 6ene8ts
2 T-e most *ommon analsis met-ods are$
= /a6a*7
= N/>= ROI= IRR internal rate of return= CBA *ost=6ene8t analsis
, T-e CBA s-ould in*lude t-e follo&in. se*tions$
= E?e*uti%e summar= Introdu*tion= S*o!e and !ur!ose= Analsis met-od= Re*ommendations= usti8*ations
= Im!lementation !lans= Summar= A!!endi?
) E?am!les of useful su!!ortin. do*umentation$
= Or.anisational *-arts= :or7Go& !lans= Floor !lans= Statisti*al information= /ro3e*t seDuen*e dia.rams= Timelines= Milestone *-arts
& *(ase 2: 6euirements at(erin$ and Analysis p1@1
'urin. t-is !-ase9 t-e team attem!ts to understand t-e reDuirements to
determine t-e main !ro6lem &it- t-e *urrent sstem or !ro*esses9 and loo7s for
&as to sol%e !ro6lems 6 desi.nin. t-e ne& sstem" Note t-at an sstem -as
, !arts$
= /ro*ess= 'ata= UI
% *(ase 2: 6euirements at(erin$ and Analysis Study Botes
1 Ste! 1 is .at-erin. reDuirements ste! 2 is !ro*ess analsis
2 T-e *reation of t-e sstem s!e*i8*ations do*ument indi*ates t-e end of t-e
analsis !-ase and t-e start of t-e desi.n !-ase
T-ere are 2 main a!!roa*-es for analsis and desi.n of information sstems
!141$
% '(e 2 -ain Approa!(es for Analysis and Desi$n of ISs
1 T-e stru*tured sstems analsis and desi.n a!!roa*- SSA'$
= Treats !ro*ess and data inde!endentl
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% '(e 2 -ain Approa!(es for Analysis and Desi$n of ISs
= SeDuential a!!roa*- t-at reDuires *om!letin. analsis 6efore desi.n
*an 6e.in
2 O63e*t oriented a!!roa*-$
= Com6ines !ro*ess and data analsis
= T-in line 6et&een analsis and desi.n
Study 'a;le 18
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% Step
) Re%ise t-e !rotot!e
Study advanta$es and disadvanta$es of prototypin$ on p1@0
0 *(ase 4: Implementation p1@0
Ta7es t-at ta7e !la*e in t-e im!lementation !-ase$
% 'as/
1 A*Duirin. ne& eDui!ment
2 #irin. ne& em!loees
, Trainin. em!loees
) /lannin. and desi.nin. t-e sstems !-si*al laout
5 Codin.
+ Testin.
'esi.nin. se*urit measures and safe.uards4 Creatin. a disaster re*o%er !lan
O!tions for *on%ertin. an IS !14+$
% Option
1 /arallel *on%ersion old and ne& sstems run simultaneousl for a s-ort time
2 /-ased=in=!-ased=out *on%ersion as ea*- module of t-e ne& sstem is
*on%erted9 t-e *orres!ondin. !art of t-e old sstem is retired e"." a**ountin.
and 8nan*e
, /lun.e dire*t *uto%er *on%ersion) /ilot *on%ersion introdu*e sstem in onl a limited area e"." a de!artment
5.1 eE*est for Proposa' =%P> p186
Study 3(i;it 18
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. Bew 'rends in Systems Analysis and Desi$n p1@
T-e S'(C model mi.-t not 6e a!!ro!riate in t-e follo&in. situations$
% Situation
1 (a*7 of s!e*i8*ations t-e !ro6lem is not &ell=de8ned
2 T-e in!ut=out!ut !ro*ess *ant 6e identi8ed *om!letel, One time !ro6lem ad -o*
) Users needs *-an.e *onstantl
.1 Ser!ice-riente# "rchitect*re =S-"> p189
% SOA Study Botes
1 SOA is a !-iloso!- and a soft&are and sstem de%elo!ment met-odolo.
t-at fo*uses on t-e de%elo!ment9 use9 and reuse of small9 self=*ontained
6lo*7s of *ode *alled ser%i*es to meet t-e soft&are needs of an or.anisation
2 T-e fundamental !rin*i!le 6e-ind SOA is t-at t-e @6lo*7s of *ode *an 6e
reused in a %ariet of dierent a!!li*ations9 allo&in. ne& 6usiness !ro*esses
to 6e *reated from a !ool of e?istin. ser%i*es
, SOA ad%o*ates t-at *ore fun*tions and dnami* fun*tion 6e de*ou!led
.2 api# "pp'ication De!e'opment ="D> p19
% 6AD Study Botes
1 Con*entrates on user in%ol%ement and *ontinuous intera*tion 6et&een users
and desi.ners
2 Com6ines !lannin. and analsis !-ase into one !-ase and de%elo!s a
!rotot!e of t-e sstem, RA' uses an iterati%e !ro*ess9 also *alled in*remental de%elo!ment t-at
re!eats t-e desi.n9 de%elo!ment9 and testin. ste!s as needed9 6ased on
feed6a*7 from users
) 'isad%anta.e$ narro& fo*us and lo& Dualit
.3 +:treme Programming =GP> p19
% K* Study Botes
1 Q/ di%ides a !ro3e*t into smaller fun*tions9 and runs in small !-ases
2 Q/ deli%ers t-e sstem to users as earl as !ossi6le and t-en ma7es *-an.es
t-at t-e user su..ests, 'e%elo!ers usuall &or7 on t-e same *ode in teams of 2 @s-arin. a
7e6oard t-is is *alled pair pro$rammin$