computer-networks-class-xii-part-1-eng.pptx

network

1. Compu t e r N e t w or k s

2. Wh a t is a N e t w ork? In a n e t w ork , t w o or mo r e c om p u t e r s a r e c onnec t ed i n a w a y s o th a t th e y c an s ha r e the i r r e s o u r ces l i k e pri n t e r , C D , ha r d d i s k e t c . A Co m pu t er n e t w or k i s a n e t w or k of c om p u t e r s whi c h s ha r e i n f o r m a tion and r esou r ces f r o m each othe r . Su c h n e t w or k s c a n b e c o nne c t ed v i a c able, t ele p h o n e line, r a d io w a v es, s a t e l l i t e, i n f r a r ed e t c .

3. Ben e fits of N e t w ork R E S O U R C E SHARIN G : N o w a d a y s , c o m pu t er n e t w or k s a r e use d in school s and o f fice s t o sha r e v arious r esou r ces li k e pri n t e r , s c anner e t c. in o r de r t o minimi z e e xpen s es o f an o r g ani z a tion. E f f ecti v e c o m muni c a tion- C o m muni c a tion ha s be c ame v e r y e f f ecti v e and f a s t with the hel p o f n e t w or k : Les s e xpen s e s- be c ause o f sh aring o f r esou r ces, c o m muni c a tion e xpens e s has dec r eased o n a f a st er r at e. R eliabili t y - With the u s e o f c o m pu t e r , c alcul a tions a n d c o m mun i ca tions b e c ame much r eliable. C e n t r al s t o r a g e o f d a t a : O r g ani z a tions a r e s t orin g their d a t a ce n t r a lly so th a t it c a n b e a v ailable t o all c on c er n ed p eople k e e p ing i n t egrity o f d a t a. Banking i s g o o d e x ample o f thi s .

4. T ermin o logy Node s ( W or k s t a tio n s) : Th e t erm no d es r e f e r s t o c ompu t e r s th a t a r e at t ac h ed t o a n e t w or k and a r e se e king to sha r e r esou r ces. Ser v er : A c omp u t er th a t f ac i li t ies the s har i n g o f d a t a, so f t w a r e and ha r d w a r e r e sou r c es o n the ne t w ork . N et w ork I n t er f ace Un i t ( N I U ) : A N e t w or k i n t er f ace u n i t i s an i n t erp r e t er th at h el p s i n e s t abl i s h in g c om m u n i c a t i on be t w e e n the s er v er and the c li e n t . IP Add r ess : E v ery machine o n a T CP / I P N e t w or k ha s a u n ique ide n ti f ying n u mber c al l ed an I P A d d r es s . Domain N a me : I t i s a w a y t o ide n ti f y and lo c at e the c ompu t e r s c on n ec t ed t o the i nt ern e t. I t mu s t be u n ique. URL ( Uni f o r m R esou r ce L o c a t or) i t s t ands f o r "Uni f o r m R esou r ce L o c at o r . " A U R L i s the a d d r ess o f a specifi c w ebpage o r fi l e o n the I nt ern e t. F o r e x amp l e, the U RL o f the T ech T erms w e b s i t e is " h t tp:// t ec h t er m s . c om. " f o r e x - " h t tp:// t ec h t er m s . c om/d e finit i on / ur l " . I t ha s f ol l o w i n g i n f or m a tion - h t t p : / / – t h e U R L p r e fix, which speci f ies t h e p r o t o c o l use d t o acc es s t h e l o c a ti on t e c h t erms . c om – t h e ser v er n ame o r I P ad d r ess o f t h e ser v er / d e finiti o n / ur l – t h e p a th t o t h e d i r e ct o r y o r file

5. Structu r e of a N e t w ork Sender : A d e vice o r c o m pu t er th a t send i n f orm a tion / d a t a. R ece i v er : A d e vice o r c omp u t er who r ecei v es d a t a/i n f orm a tio n . Messa g e : A n i n f orm a tion ne ed s t o b r oad c a s t . T r ansmiss i on Medi u m : I t is a p h y si c al p at h with the hel p o f which i n f orm a tion g oe s f r o m send e r to r e cei v e r . P r o t o c ol : I t is a c oll ec ti o n o f rules which r e g ul at es t r an s f er o f i n f orm a tio n .

6. ARPANET ARPANET -basis for the Internet. ARPANET was developed under the direction of the U.S. A dvanced R esearch P rojects A gency (ARPA). In 1969, the idea became a modest reality with the interconnection of four university computers.

7. I N TERNET I nt ern e t i s the l a t e s t t ech niq u e o f i n f or m a t i o n b r oa dc a s ti n g . I t is basi c a l ly a c ol l ection o f c o mpu t er n e t w or k s t h r oug h o u t the w or l d. Th o usan d s o f c om p u t e r s a r e c on n e c t ed t o each o t he r in this n e t w ork . G e ne r a l l y , c ompu t e r s a r e c o n ne c t ed vi a t e l e p h o n e l i n e s . Ot h er o p tion a r e al s o the r e f o r c o n n ection b y which a c ompu t er c an g e t c on n ec t ed t o i nt ern e t. I nt ern e t i s no t subje c t t o a n y c omp a n y o r g o v ern m e n t but i t has s ev e r al s e r v e r s which a r e r el a t ed t o v ar i ou s o r g a ni z a t i on s or pri v at e c ompanies . W e c an s a y th a t i nt er n e t i s a med i u m f or w or l d w i d e c o m m u n i c a tion. I t i s an ea s y a n d f eas i bl e m e diu m to anal y si s a n y p r odu c t a t a n i n t e r n a t i o na l l e v e l . I t i s a n e f f ecti v e m e diu m t o p u bli s h v ar i ou s i n f or m a tion l i k e r eport, art i cle e t c . I t i s w or l d ’ s bi g g e s t W A N .

8. I n t r an e t i s a pr i v a t e n e t w o r k of c o m pu t e r s whi c h w or k s on i n t er n e t p r o t o c ol s f o r w o r k in g . A n y o r g ani z a tion c an u s e i n t r a n e t f o r s e cu r e t r ansmission of in f orm a tion among s t it s emplo y ee s . I n t ern e t i s a n e t w o r k b e t w e e n v ario u s o r g an i z a t i on s whe r eas i n t r an e t i s a n e t w or k of on e o r g ani z a t i o n onl y .

9. Circuit switching and Packet switching

10. R E VIEW N e t w or k : A c ol l e c t ion of ind e p e nde n t c ompu t e r s t h a t c ommun i c at e with on e another o v er a sha r ed n e t w or k med i u m. Node : A c ompu t er a t t ached t o a n e t w or k . Se r v e r : A c ompu t er th a t f acil i t a t es shari n g of d a t a, soft w a r e and ha r d w a r e r esou r ces on the n e t w or k. N e t w ork I nt er f a c e Un i t ( NIU): A d e vice t h a t he l p s t o e s t abl i s h c om m un i c a tion b e t w e e n the se r v er and w or ks t a tions. Ci r cui t s w i t chin g: A t e chni q u e i n w h i ch a d e d i c a t ed and c omp l e t e p h y si c al c onn e ct i o n i s e s t abl i she d b e t w e e n t w o no d es f or c om m un i c a tion. P ac k e t s wi t chin g: A sw i t c h ing t e chni q u e i n which p ac k e ts a r e r ou t ed b e t w e e n nod e s o v er d a t a l i n k s sha r ed with othe r t r a f f i c. P e r son a l A r e a N e t w ork ( P AN): A c ompu t er n e t w or k o r g ani z ed a r ound an in d iv i dua l pe r so n.

11. L o c a l A r e a N e t w o r k ( LAN ) : A n e t w or k i n wh ic h the d e vic e s a r e c onn e c t ed o v er a r e l a ti v e ly shor t d i s t anc e . M e t r o p oli t an A r e a N e t w ork (MAN): A n e t w or k which span s a p h y si c al a r ea ( i n the r an g e of 5 and 5 km d ia m e t e r ) th a t i s la r g e r than a LA N bu t small e r than a W A N . Wid e A r e a N e t w ork ( W A N): A n e t w or k which sp a n s a la r g e g eog r aphi c al a r ea, of t en a c ou n t r y or a c o n tin e n t . It i s a n e t w or k of n e t w or k s sp r ead ac r os s the globe I n t ern e t: all of which a r e c onn e c t ed t o each othe r . I n t e r sp a ce : A cl i e n t / se r v er so f t w a r e p r og r am t h a t al lo w s mult i p l e use r s t o c om m un i c a t e onl i n e with r e al time a ud i o , vi d eo and t e xt ch a t i n dy n amic 3 D e n vi r onme n t s . Cha nnel: A med i u m t h a t i s use d i n t h e t r an s mission o f a mes s a g e f r o m on e poi n t t o anoth e r . Bandwidth : Th e r a n g e of f r e q ue nci e s a v ai l able f o r t r ansmission of d a t a .

12. T y pe s o f N e twork P AN – P E R SON A L A R E A N ET W ORK : P A N s a r e s m all n e t w or k s whi c h c an be e s t ablis h ed t o s e t c o m muni c a tion b e t w e e n c o m pu t er and h a n d h a n d ed de v i c es. Its m a ximu m d i s t an c e c apabili t y is 10 m e t e r . F o r e x- c o n n ection o f t w o d e v i c e s by Bl ue t o o th, c onn e ction o f c o m pu t er a n d m o bil e via U S B. P A N s a r e us ed t o t r an s f er files , e - mails e t c in c o m pu t e r s , m o bile s and t abl e ts e t c. L A N – L OCAL AR E A NET W ORK : I t ’ s a smal l ne t w or k o f c ompu t e r s t o sha r e r esou r c e s. It i s in a limi t e d a r e a li k e r e s i d e n c e, s c h o o l, la b o r at o r y , uni v e r sity c ampus an d o f fic e buildin g e t c. M A N – ME T R O P OLI TI AN N ET W ORK : It i s a c o m pu t er n e t w or k w hic h sp r ea d s o v er a city li k e a r e a . M A N is basi c ally c ollectio n o f smal l LAN s . W AN – WIDE A R E A NET W ORK : It is wide t e l e c o m muni c a ti o n ne t w or k whi c h sp r ea d s o v er a v e r y h u g e g eog r aphi c al a r ea . It c a n b e th r oug h ou t a c ou n t r y or w orl d .

13. C O MMUNI C ATION/TRA N SMISSION M E DIA GUIDED ( W IR E D) U N GUID E D ( W IR E L E SS) T w i s t ed P air Ca b l e Co a xial Ca b l e O p t i c al Fib r e Ca b l e I n f r a r ed W a v es Rad i o W a v e M i c r o w a v e S a t el l i t e Blu e t ooth & W i -Fi

14. TWI S TE D P AIR( E thern e t) CABLE 2 o r 4 insul a t ed wi r es a r e in tw i s t ed f orm i n this c abl e . T wi s ting r esi s ts the e f f e ct of sur r oundin g noi s e and ele c t r o ma g n e tic i n t er f e r en ce . RJ - 4 5 ( r egi s t e r ed ja c k ) c o nne c t o r is use d t o c onnec t c ompu t e r s. C a t- 5 and C a t - 6 specifi c a ti o n s a r e g ene r ally use d in LA N w h e r eas ot h er l o w er c at e g orie s a r e use d in t ele phon e c onnections. It is furthe r divide d in t o c a t e g orie s -unshield e d and shield e d twi s t ed pai r c abl e . Shi e lded twi s t ed pai r c able r emains c o v e r ed with insul a ti o n t o r educe signa l i n t er f e r ence . Ad v a n t a g es : Che a p , li g h t w eig h t and fl e xible c able. It is ea s y t o in s t all and mai n t ain. Disad v a n t a g es : It is e f f ec t i v e u p t o 100 m e t e r s onl y a f t er this, r epe a t e r s a r e r equi r ed. It s upport s low bandwidt h with the spee d u p t o 10 Mb p s. Shielde d T w i s t ed P air Unsh i elded T w i s t ed P air

15. C O A X IAL C A BLE(co a x) I n a c o a x , t he r e a r e t w o so l id insul a t ed c onduc t o r s which sh a r es one c ommo n a x i s . Inner c o n duc to r is a s t r aig h t wi r e sur r ound e d b y a wi r ed mesh . I n t ern al c o r e c arri e s si g nal s and mesh w or k s as a n o ise r e fle c t o r . I t is g en e r ally use d in c able T V t r ansmissi o n . A D V A N T A G E S : I t p r o vides hig h bandwidt h . I t c arries d a t a u p t o the di s t a nce of 185 - 50 me t e r s . I t is sui t able f o r b r oa d ban d t r an s miss i o n ( c ab l e TV ) and c an al s o b e us e fu l in sha r ed c able n e t w or k . I t is less sensiti v e t o w a r d s elect r omagne tic field s . DI S A D V A N T A G E S : As c o mpa r ed t o twi s t ed pai r c abl e , it is less f l e xibl e and is e xp e nsi v e . In st all a tion i s no t ea s y du e t o thi c kness o f 1 c m diam e t e r e and po o r fl e xibili t y .

16. O P T I C A L F I B R E CA B LE Its desi gn i s base d o n the c on c e p t o f t o t al i nt ernal r e fle ction. • It ha s gla s s tubes t o c arry s igna l s in the f or m o f l i g h t ra y s ( p ho t ons) . Signal s a r e t o be e m i t t ed b y Li g h t Em i t ting Diod e (L E D ) o r la s er bea m f r o m sou r ce. It ha s f o l l o w i n g part s- C OR E(Glass/Pl a s t ic ) : i t i s a th i n glass r ode , li g h t r a y s t r a v els f r o m on e end t o o t he r . C L ADD ING : i t i s an o p ti c al m a t er i al c o v er i n g c o r e th a t t r ans f orm s the li ght a n d s en ds i t b a c k t o the c o r e . BUFFER C O A TING : i t i s a pla s t ic c o a t i n g wh i c h p r ev e n ts the c able f r o m da m a g e and moi s tu r e . A D V AN T A G E S : It i s f r ee f r o m E lect r oma g ne t ic I n t er f e r en c e(E M I). It i s s e c u r e and s u i t able f o r hig h s p e e d t r an s mission. DI SA D V AN T A G E S : It i s f r ag il e and v e r y e xp e n s i v e. – Its in s t al l a t i o n i s v e r y t ou g h and e xp e n s i v e .

17. F A C T O R S TWI S TE D P AIR C AB L E C O AXIAL CAB L E OPTICA L FIBRE CAB L E D AT A TRANSFE R R A TE 10 Mb p s – 10 Gb p s 100 Mb p s >10 0 Gb p s DI S T ANCE( r ange) 100 m 185 -500 m >1 0 KM E M I s u s c e p t i bi l i ty Mo r e Le s s Nil C O S T Le a s t c o s t Mo r e than T w i s t ed P air V e r y e xp e n s i v e

18. W I RELES S M E DIA RADIO W A V E S Ra d io w a v es use s r adio f r equencies in t h e l i m i t 3 GHz t o 3 Gh z . Sig n als a r e modif i ed o n hig h spee d r adio w a v e c ar r i e r f r equency usin g a m plitud e modul a tion ( AM) and f r equency modul a tion ( F M ) . Thes e w a v es uses ionosphe r e as sh o wn in the diag r am f o r s i g n al t r ansm i s s ion. It c an b e t r ansm i tt ed o n l on g di s t an c e and sup p ort s mob i l i t y . Ra d io w a v es a r e use d f o r c om m u n i c a tion f r o m s m all w alk i e - t alk i e di s t an c es t o su f ficie n t di s t an c es w i thin a city (A M / F M r adio b r oadca s tin g ) .

19. A D V A N T A G E S : Radio c ommu n i ca t i o n c o v e r s a b ig a r ea and su p por ts mob i l i t y . R a di o w a v es c an dis p e r s e in all di r ections and c an c r os s the sol i d w al l s as w el l . Thes e w a v es f acil i t at es the c ommu n i ca t i o n in i nac c ess i b le a r eas. It is no t need ed t o p h y si c al l y al i gned t r ansmi t t er and r ecei v er a n t enna. DI S A D V AN T A G E S : It is e xpens i v e and un s ecu r ed c ommun i c a tion med i um. It is v ery sens i ti v e t o w a r d s w e a the r . . – P ermissi o n f r o m c oncerne d departme n ts is r equi r ed f o r r adio w a v es t r ansmission.

20. M ICROWA V ES In m ic r o wa v e t r an s mission, t w o di r ect pa r ab olic a nt ennas a r e n eeded t o in s t all on t o w e r s/ building s /m o u n t ain s f or s endin g an d r eceiving signa l s. Th e y a r e neede d t o aligned t o eac h othe r . A D V AN T A G E S : Thi s f ac i l i t a t es t r ansmissio n in t ou g h a r e a s. It suppo r ts d a t a t r ansmissio n a t the sp e ed o f 1 6 Gi g a bit s p e r s e c ond. DI S A D V AN T A G E S : It is an uns e cu r ed c o m muni ca ti o n . Si g nal s a r e di s tribu t ed and t r ansmi tt ed in all di r ecti o n s. – It g e ts a f f ec t ed b y w eather c ondi ti o ns. – Co s t o f placin g t ow er and a n t enna is hi g h.

21. I NFR A RE D W A VES I n f r a r ed w a v es al l o w s t r ans m ission i n d e v i ces up t o s m a l l di s t an c es o f 3 00 GHz t o 400 TH z (abou t 5 m e t e r s) usin g w i r e l e s s s i g n al s . I n f r a r ed t r ansm i ssio n t ech ni q u e use d i n c om p u t er i s s i milar t o the t ech ni q u e use d in r e m o t e ope r at ed e l ect r oni c equipme n t l i k e T V , c o r dles s p h on e t o y s e t c . Ad v a n t a g e s : It i s a k in d o f li n e o f sig h t t r ansm i s s i on. It do e s no t r eq ui r e g o v ernment L i c en c e. It i s ba s i c al ly f o r le s s di s t ance t r an s mission. Disad v a n t a g e : It i s a k in d o f li n e o f s i ght t r an s mission, the r e f o r e, a t a t ime, onl y t w o de vi ces c an c omm u ni c a t e w i th ea c h othe r . It c an no t t r a v els th r ou g h sol i d ma t er i als. It ge ts a f f ec t ed by lon g di s t ance s .

22. S A T E L L I TE L I NK S a t elli t e c ommuni c a ti o n use s m i c r o w a v e ( 1 . 5 GHz - 20 GHz) as a mediu m . S at elli t es li k e Geo s ta ti o na r y o r P ola r s a t elli t es a r e use d t o s e t t r ansmis s ion o n v arious c e n t er o n earth. S er vices l i k e D TH , V S A T , G P S S at elli t e phones , e t c . h a v e be c a me p os s ible b y s a t elli t e t r ansmissi o n. A s a t elli t e w or k s as a r e g en e r a t e and r edi r e ct signals . A D V AN T A GE: – It c o v e r s a la r g e g eog r aphi c al a r ea. T r an s- R e cei v er A n t enna in spac e which r e cei v e, It p r o v i de s secu r e, u ni nt er r up t ed and hig h q u al i ty t r ansm i s s io n . G e og r aphi c al c on d it i on s l i k e mou nt ains, t all b u i l din g , t o w e r s doe s no t r ai s e i nt er r upt i on. Sig n als se n t o r r ecei v ed b y earth s ta tions m a y b e fi x ed o r mob i l e . DI SA D V AN T A GE: Thes e a r e s l o w than m i c r o w a v e t r ansm i s s ion. l e g al perm i s s i on s a r e neede d f o r these. In s t al l a tion is v ery c ompl e x. Sig n als can b e i nt er r up t ed b y e x t ernal i nt er f e r enc e .

23. C l ien t - Server A r chitecture In this model d a t a is s t o r ed in p ow e r f u l c o m pu t e r s, th e se c ompu t e r s a r e known as se r v e r s . Thes e a r e g ene r al l y m ai n t ain e d b y s y s t em admini s t r a t o r . O t he r e m pl o y e es w o r k s on o t he r machines, known as cli e n ts . T h is s ys t em is t e r med as clie n t - se r v er model .

24. C l o u d C o m p u t ing Clou d c omputin g i s a kind o f di s tr i b u t ed d a t a p r ocess i n g t ech niq u e. Clou d c om p utin g i s a s tyle o f c omputi n g i n which dy namica lly s c alable and of t en v i rtual r esou r ces a r e made a v ai l able as a se r v i ce o v er the I nt ern e t . A d v a n t a g e s - L e ss i n v e s tm e n t - a n y w or k c an b e initi a t ed o n l e s s o r z e r o b a l ance. Ma in t enance i s also l e s s e xp e n s i v e. Hi g h Sp ee d - c lou d c omp u t i n g c an p r o vide r eq ui r ed r e sou r c es i n l e s s t ime. R e lia bi l ity - i t i s p r o vided by r el i able c omp a nies / o r g ani z a t i on s , h e nc e i t i s v e r y r el i able. Scalabil i ty - i ts c apa c i ty c an b e p u r c ha s ed as p e r y ou r fluc tu a t i n g r eq ui r em e n ts. E n vi r o nme n t s u pp o r t - cl o ud s a v e s e n e r g y as w e ll as mi n imi z e carbon e x c r et i on. Disad v a n t a g e s - On l i n e P r i v acy and s e c uri ty i s no t s a f e. Y o u c an no t ac c e s s y ou r d a t a w i thout i n t ern e t. It i s o f t w o type s- P ubl i c C l ou d – ( Google D ri v e, Ama z o n C l ou d D ri v e e t c .) P r i v a t e C lou d – ( O wned by on e o r g ani z a t i on)

25. I n ter n e t o f T h i ng s ( Io T ) I t is a n e t w o r k of p h y si c al obj ects . I o T , enabl es the i n t e r c onnec t ion via the i n t e r n e t of c ompu t i n g d e vices e m bedd e d in e v e r y d a y obj ects, enabli n g them t o sen d and r ec ei v e d a t a . In e a s y l angua g e, all c onn e c t ed t o i n t e r n et T h ings . Its c ompone n ts a r e – Sen s o r s Connectivi ty P eople and P r oces s e s the t h ings th a t a r e a r e c al l ed I n t e r ne t of

26. N E TWORK D E VICES Networ k d evices ar e als o kno w n as co m munica t ion d evices whic h ar e u sed to set n etwork. These ar e as follows - NI C ( N etw o rk Interface Card) Hub Swit c h R e p e ater Gate w ay R o uter WAP (Wi r eles s A c ce s s Point)

27. HUB Hu b is a bro a dc ast d evice whic h con n ects several comp u ters to g et h e r . It can no t h a n d l e n e two r k traff i c . Mes s a g e is d e li v e r e d from on e computer to r est o f al l computers i . e . b r o a dcas t ing . In a Hub , p orts ar e the r e w h i c h ar e use d to conn ect NI C o f computers .

28. S W I T C H Switch is a type of Hu b. It contains a fi l ter whic h f ilters the d ata b efore sen ding and i t is th e n direct e d to the int e n d e d node o nl y. It is an intelligen t Hu b. •

29. R e peater It is a d e v i ce w h i c h ac c e pts the wea k s i g n al s an d amplifie s the s i g n al s for further b r o a dcas t ing . With the us e o f it , s i g n a l len gth incre a se s . It is als o known a s amplifie r . Mostly used in Cable TV network to extend the network.

30. G a teway On i nternet, w h e n two o r more network s u s e s differen t har d w a re an d software then gate w a y i s use d t o set coord i nati o n betwe e n them . I t conv er t s on e net w or k l a n g u a g e i nt o an o ther net w or k l a n g u a g e so that they can comm un i cate .

31. R o uter Ro uter is a l so a n e two r k i n g d e vice w hic h sent d a t a p ackets from sour c e mach i n e to d e s ti n ation machin e . It tak e s the shortest p ath for thi s . R o u te r , w o rks o n third laye r (NET W O R K LAYER ) o f OSI r e fer e nc e mo d el .

32. W i reless A c cess P o i n t ( W A P) It is al s o a type o f d e v i ce w h i c h p r o v i d e s wir e l e ss c o n n ecti o n f a c i l it y to a wi r e d n e two r k a s pe r W i- Fi r u le s . Its tra n s m i s s i o n medium is ai r. A WAP, can b e s t a n d a lo n e. A WAP, can b e conn e c te d to a r o ute r. It can b e a par t o f r o ute r (wir e les s r o ute r ) .

33. S e t ting u p a c o m pute r n e twork Th e 80 - 2 Th u mb R u le : Ac c o rd in g t o this r ule , i n a p r o p e rly d e s i gne d and organize d net w ork , 80% of t h e t r af f i c o f w h ole netwo r k s h oul d be dedi c ate d t o lo c a l netwo r k . 20% of w h o l e tra f fic sh o ul d not exc e e d b a ckbon e . I f i t hap p e n s , t h er e m a y be a cond i tion of netwo r k c o nge s tion a r is e s . We need t o follow abo v e ru le s w h il e de s ignin g a netwo rk .

34. E a s y w a y to s o l ve q u estions Whe r e t o s e t Se r v e r ? : A t the plac e with m a ximum numbe r o f c o m pu t e r s. A t wh a t p l ace f ollowi n g d e vice s a r e t o b e use d ? : Se r v er : The buildin g with m a ximum numbe r o f c o m pu t e r s. HUB/ SWI T C H : In e a ch building . Mod e m : The buildin g with s e r v e r . R epe a t e r : buildin g s h a v in g di st ance mo r e than 7 m e t e r s so th a t cha nne l c an b e ampl i fie s. R ou t er : when a L A N is t o g e t c onnec t ed with othe r L A N . B e s t Ca b le : T wi st e d P air , E t herne t Ca b le (wh e n the di st a nc e is in m e t e r s and ne e d s t o b e f e a sibl e. ) , c o a xial c able ( when hi g h sp e ed is r equi r ed ) B e s t Ca b le : Fiber Op ti c al Cabl e (wh e n di st ance is in ki lo m e t e r s and hi g h sp e ed is r equi r ed. B e s t Co n n e cti n g T e c hniq u e : In Hilly a r e a s sa t el l i t e s i gn a ls , f o r city t o city r a di o w a v es and s t a t e t o s t a t e s a t e l i t e si g n a l .

35. A n e x ample 110 30 140 40 50 80