Ｃhapter2ApplicａｔiｏnＬａyer1.Ｉnｔhefollowingfourdｅsｃriptions,whiｃhｏneiｓcoｒrecｔ?AInC/Ｓarcｈｉtecｔｕre,ｃlienｔsｃommunｉcateｗiｔheａｃhotherdirectly.BInＣ/Ｓarｃhｉteｃｔure,cｌｉentｈaｓaｆixeｄwell-ｋｎｏwｎａddresｓ．CＩnＰ2Paｒchｉｔｅcture,peeｒsｃｏmmｕnicatewｉtｈｅaｃhotheｒdirectlｙ.DInＰ2Parcｈitectｕrｅ,peerhａsafｉｘedwelｌ－knｏwnaddrｅss.２.Inthecｏntｅxtｏfａcommｕｎicatｉonseｓsｉonｂeｔweenａpairofｐrocess,theprｏcessthatinitiａt(yī)eｓｍuniｃatiｏnisｌａbeleｄａｓthe，tｈepｒocｅsｓthatwaitsｔobｅconｔａｃｔｅdtobｅgｉntheｓessioniｓlabeledastｈe.Aclienｔｐｒocｅss,seｒｖerproceｓsBｓendingprｏcess,recｅivingproｃeｓsCiｎｐutprocｅss,oｕtputpｒoｃｅsｓDｃommuｎｉcatingproceｓs,coｎｎectingprｏｃeｓs３.Asockｅtiｓtｈeｉnterfaｃｅｂｅｔweenwiｔｈiｎａhost.ＡworklａｙeｒandtheｌｉnkｌａｙerBthｅliｎklayeraｎdｔhephｙsicaｌｌaｙerCtｈeapｐlicａt(yī)ionｌａyerａnｄtheｔｒansportlaｙerDｔhetransｐortlayeｒaｎdthenetwｏrklayｅr4.Inthefｏllｏwingapplications,whiｃhｏneisaｌｏｓs－tolerａnｔapplicaｔiｏn？AE-mailBfiｌeｔransferＣinstanｔmessaginｇDreal-tｉmｅauｄio5.Intheｆolｌowingａpplicatioｎs,whichoneisabandwiｄtｈ－sensｉtivｅａｐpｌiｃａｔiｏn？AＥ-mａilＢwｅbapｐliｃatｉoｎＣreａl-timeaｕdiｏＤfｉlｅtrａｎｓfer6.TheseｒｖicｅofTCPｃａn’tｇｕarａｎｔee．AｄeｌiveryｏfalldatａwｉｔhoutｅrroｒBdeliｖeｒyofalｌdａｔainthｅpｒoperorderCtherateoｆdeliveｒyＤconｇeｓtｉoncontｒol7.Inｔheｆｏlｌoｗingaｐｐｌicatiｏns,ｗhｉchonｅuｓeｓUＤＰ？ＡE－mａｉlBwebapplicaｔiｏnCfilｅtranｓferＤDNＳ８.InｔhｅｆｏllowinｇdｅscｒiptionsaboｕtHTＴP,whｉchonｅisnoｔcｏrrｅct?ＡHTTPｕsｅｓnon－pｅrsisｔeｎtｃonneｃtiｏnｓinｉtｓdeｆaultmoｄe．ＢHTTPｕｓesTCPaｓitsunｄerlyｉngtraｎsportprotｏcol．CHTTPｉsaｓtateｌesspｒotocol．DHＴTPisclieｎt－ｓｅrverarchitectuｒe.9.SuｐpｏsｅaweｂpaｇｅｃｏnsisｔsofａbａsｅHTMＬfｉle,５JEPGimaｇesandajavaaｐpleｔ,andalsosｕppoｓｅHＴTＰuｓｅspｅｒｓistentconnectiｏｎwiｔhｏｕｔpipｅlining,ｔhetotalｒespｏｎseｔimｅis.A2RＴTＢ8RTTＣ1２ＲＴTD1４ＲＴT10.IｎHTTＰｒesponｓemｅsｓage，iｆtｈereqｕeｓteｄＨＴTPprotｏcｏlvｅrsionisnotｓupported，thestａt(yī)uscｏｄｅｉs.A2０0Ｂ30１Ｃ４001~5

ＣACDC

6～10

CＤＡＢＤ11.Thepoｒtnumberofwｅｂapplｉcationis.A2５B20C80１2.AnｅｔworkｅntitythatsaｔisfｉesHTTPrequesｔsｏｎｔhebeｈａlfoｆanoriｇinwebserveris.AserverｆaｒｍBsｅrveｒstaｃkＣｐｒoxysｅrvｅrDeｄgeｓｅｒver1３.Intｈefoｌlｏwｉngdescripｔionsaboｕtｐeｒsisｔｅntcoｎｎecｔion,whichoneisnotcorrect?AＴheｓerｖeｒｌeavestheＴCＰｃoｎnectiｏnoｐenａfｔeｒsenｄinｇarespｏnse.BEａcｈTＣPconnｅcｔioniｓclosedafteｒtheserveｒｓenｄingoneｏbjecｔ．ＣTherｅaretwoｖｅrsioｎsofｐersｉsｔentcｏｎneｃｔiｏn：ｗｉｔhｏutpipｅlｉninganｄwｉthpipelｉｎing.ＤTｈedefaultｍoｄeoｆHＴＴＰｕsesｐｅrsｉstenｔconnectionwitｈpipeliｎｉｎg．14．FTＰusesｔwoparａlｌelTCPｃｏnnｅctionｓtotｒanｓfｅrafile,thereare.AｃoｎtrｏlcｏnnectionａnddataconｎectionBreｃeｉvinｇcｏnnectｉonandｓｅｎｄinｇcoｎnｅcｔionCcｌiｅntconnｅcｔionａnｄseｖｅrconnectｉonＤprｏgrａmconnectiｏnａndprｏｃeｓsｃonnection１５.InｔhefolｌowｉnｇdesｃriptｉonsａbouｔFTP,whichoｎeiscorrect?ＡFTPisp２parchitｅctｕre.BFTPsendsitsｃonｔｒｒmatiｏｎoｕt-of－band.CFＴPｕｓespeｒsisｔｅntconnｅｃtion.ＤFTPisastatｅlesｓｐrotｏcol.16.

Iｎ

tｈe

ｃｏmmands

of

FTP,

ｗｈich

one

ｄoes

ｎot

have

ｐaｒaｍｅteｒ?

A

USEＲ

B

PASS

C

ＬＩST

Ｄ

STOＲ17．TheIｎternetｍailsystemhasthreeｃｏmponenｔｓwhichtheyare.Auseragｅnt,ＳMTP,PＯP3ＢSMTP，POP3,IＭAＰＣuseｒａｇent，SMTP，ＩMAPＤusｅｒagent,ＳＭTP,maｉlseｒver1８.IftheｓtatuscodeinＨTTＰrｅsponseｍessaｇｅiｓ４０4,itmｅａns.ARｅｑuｅsｔｓucceedｅd.BTｈｅｒequesteddｏcｕmeｎtdoesｎ’ｔeｘitonｔhiｓservｅr.CThｉｓiｓagenｅｒｉcerrorcoｄeindｉcａｔingｔｈattherｅquestcouｌdnｏtbeunderstｏodbytheｓｅrｖer．DReqｕｅstedｏbjeｃthasbｅe(cuò)nperｍaｎｅntlymover.1９．ＣomｐarisonHＴＴPwｉthSMＴＰ,tｈecoｒｒｅcｔis.AHTTPisａｐｕtｏcol,andSMTＰisapuｌlprｏｔocol．ＢIｎｔhｅｄefauｌtmode，bothofｔhｅmuｓepersiｓteｎtcoｎnectｉon．CＨTTPｐlacesａllofthemessaｇe’ｓobjectsintｏonemessａge,andSMTPseｎdsｅvｅｒｙobjectonebyｏne.ＤHTＴPreqｕirｅｓｅacｈmｅssagetobｅin7-bitＡＳCＩIforｍat，andSMTPdoesｎ’timposｅthisrｅsｔriｃtｉｏｎ．２0.TheheaｄｅrsiｎｔhｅMＩMEmesｓagemｕstincｌudeexｃepｔ．AFｒoｍBConｔｅｎt-typeCCｏntent-transfｅr-ｅncｏｄiｎgDMIMEｖersion１1~１５CＣBAB

16～２０

DDＢBＤ2１.Ｉnthｅfollowｉngprotocol,wｈiｃhoneiｓｓtateleｓs?AＰＯＰ３BＳMＴＰCFTＰDIMAP22.DNＳｍeａｎs.ADａt(yī)ａＮameSyｓteｍBDaｔaNatioｎａlSysteｍCDomaiｎNaｍｅSyｓtemＤDｏmａiｎＮatioｎalＳystem2３.Thｅreaｒethrｅe(cuò)ｃlassｅｓofDNSｓｅrverexcｅpt.ARootDＮSserｖeｒBLocalDNＳserｖerCTLDserverＤAｕthorｉtａt(yī)ｉvｅDNSseｒｖｅｒ２４.DNSprｏｖideｓsomeｓervｉｃesexｃept.AHostaliａｓingBMaｉlseｒveraliａsingCＬoaddｉstｒiｂutioｎDAsinｇlｅpoinｔoffａｉlｕre2５．

There

arｅ

three

ａrcｈiteｃturｅｓ

for

locating

content

in

P２P

fｉle

ｓｈａｒｉng,

KａZaA

useｓ

.

A

Cｅｎtralized

Direｃtory

(Napｓｔer）

B

Querｙ

Floodiｎｇ（Gｎutｅｌla)C

Exｐｌoiting

Heterogeneiｔy

(p141）

D

Inｃenｔｉｖe

Pｒioｒiｔies

２6．

Ｔhere

aｒe

three

ａrchｉｔectuｒeｓ

ｆor

loｃａt(yī)ing

contｅnt

ｉn

P2P

fｉle

sharing，

Nａｐsteｒ

uｓｅs

．

A

Ceｎtraliｚｅd

Dirｅctoｒy

(p13７)

B

Query

Fｌoodinｇ

C

Exｐloitｉng

Hｅｔerogeｎｅity

D

Incｅntive

Priｏrｉties2７.

The

following

architeｃtures

in

P2Ｐ

file

sharing,

wｈicｈ

is

an

oｖerlａy

ｎｅtwｏｒｋ?

A

Ｃentｒalｉｚｅｄ

Direｃtory

B

Ｑuery

Floｏｄinｇ(p１39)

C

Exｐloiting

Heterｏgeneｉty

D

Ｉncenｔive

Priorｉties

２8.Thetimeittａｋesforasmａllpackettotraveｌfromcｌｉenttｏservｅrandtｈenbaｃｋtｏｔhecｌienｔis．Aroｕｎd-ｔｒavｅｌtimｅＢnｅxt-hoｐｔimeＣｒouｎd－triptiｍｅDpｒeｆｉx-ｍａt(yī)chｉngｔime２9．ＳｕppｏseＡ(ｗithaWeb-ｂasｅdｅ-mailaccoｕnt)ｓｅｎdｓaｍessａgｅtoB(whoａｃcesｓｅshｉsmａｉlｓerverusingPOＰ3),whicｈａｐplicatｉoｎ-laｙｅrｐrｏｔｏcolisnotused?AHＴＴPBSMＴPCPOP3DＩMＡP３０.Iｎｔhｅｆourfolloｗｉngopｔions,wｈicｈprotocolisｉncludｅｄinMailAcceｓｓＰrｏtｏｃoｌ?ASＭTPBDHCPＣIMAPDFTＰ31.IｎFＴPcommａnds,ｉsusedｔｏｓenduｓeｒpaｓswoｒｄｔotｈeserver.AUseｒBＰasｓCＲetrDＳtor32.ＴheｆunｃtｉonｏfthｅａddｉtionaｌheaｄerｆｉeldiｎＭIMＥCoｎtｅｎｔ-Tｙpeis.Atoｃｏnvｅｒttheｍeｓsagｅbodytoitsoriginnon-ＡSCＩIfｏｒmBｔｏｄｅterｍinewhatactｉonsiｔｓｈoｕldtａｋeonｍessagebodyＣtoseｎdａnE－ｍaｉltotherｅceivｉngusｅraｇentDtoindicａt(yī)ewｈattｙpethｅmessagｅis３3.Inｔhefouｒｆollｏwｉｎgｏpｔiｏns,whichaｐpｌicationisorgａnizedａｓhybridｏfC/SａnｄＰ2Pａrｃｈｉtecｔure?ＡＥ-ｍａｉlBＯICQCFiletransferＤWebapｐｌｉcaｔion３4．

Ｉn

the

ｆouｒ

folloｗinｇ

opｔiｏnｓ，

whｉｃh

is

not

a

cｅntralized

ＤＮＳ

desｉgn’s

ｐroblｅｍ?

A

a

sｉｎgle

pｏint

oｆ

ｆａiｌure

B

tｒａfｆic

ｖolume

C

ｄｉｓtant

ceｎtraｌiｚｅd

datａbaｓe

D

ｓlow

（maintｅｎance）Iｎｔｈeｆｏlloｗiｎgｏptioｎs,ｆromtｈｅａpｐlicaｔiondevelopｅr’ｓｐeｒspｅｃtive,wｈｉchｉsnoｔcorreｃt?AｔhenetworkａrcｈitｅcturｅisfｉxｅdＢｔheｎeｔworkａｒｃhitecturepｒoviｄesａsｐｅｃifｉcｓeｔoｆservicｅstoappｌｉcａt(yī)ionsCtheａppliｃaｔｉｏnａrchｉtｅcturｅiｓdesigｎｅdbytheｐhysｉｃａldevicesＤthｅapplｉcatｉoｎａrcｈｉtecturedｉctaｔeshowtheａpplｉｃatiｏnｉsｏrganizedｏverthｅvaｒｉousendｓystems３6.Thｅrｅaｒｅthｒeepreｄoｍiｎanｔarｃhitecｔurｅｓｕseｄinｍｏｄeｒnneｔｗorkａpplｉcaｔions，whｉchonｅisｎｏtiｎclｕｄed?Ａｔheｃliｅｎt-ｓｅrvｅrarｃhitectｕreＢtheＰ2PａｒｃhｉtectureCaｈｙbridofｔhｅｃlｉent-sｅrｖerａnｄP2ＰａrｃｈitｅｃｔuｒｅＤａｈybriｄofthecliｅnｔ－seｒｖｅｒandbｒｏwser-servｅｒarｃhiteｃturｅ３7.ＩntheｆoｌlｏｗｉｎｇoptionsaboutC/Sａｒchｉtecｔure,ｗhichｉsnotcorrect？AInC/Ｓarｃｈiteｃｔｕrｅ，ｔhereiｓanａlwａys-oｎhosｔ,calledtｈｅserｖer.ＢＩnC/Sａrcｈitecture，tｈeｒeisanalｗays-oｎhｏst,calleｄtheclient.CTｈeserveｒhaｓaｆixed,ｗeｌｌ-knownaｄdrｅss,calｌedIPａdｄress.DCliｅｎtsdonoｔｄirectｌyｃｏmmｕnｉcatewitheachｏtｈｅr.3８.

ａre

often

used

to

ｃreate

a

poweｒfuｌ

vｉrtual

sｅrvｅr

iｎ

Ｃ/Ｓ

ａｒchitectｕrｅ.

A

Peers

B

Ｓeｒver

fａrｍ

Ｃ

server

sｔack

D

locａl

server39．Aprｏcｅsｓｓendsｍessａgesinto,andreceiｖesmessagesｆｒom,ｔhｅnｅtworkthｒougｈits.AsockeｔBprogramCclienｔDpeeｒ40.Wｈichoｎeisnｏｔdefinｅdbｙanaｐpｌiｃatioｎ－layerｐrotｏｃol?AtｈetｙpｅsofｍessagesexchａngｅdBthｅｓｙntａxｏfvariousmｅsｓaｇｅtypesCtｈｅsｅｍanticsofｔhｅfieldsＤrulｅｓfｏrdｅｔeｒｍinｉngwｈenａndhowｔoｔｒanslａt(yī)etｈesocｋet41.HTTPｃanuｓｅtｗｏｔypeｓｏfｃoｎnections,ｗｈichａrｅ.Apeｒsｉｓtenｔanｄｎon-persistenｔｃonnｅctionBconnectionwｉthpipeliｎiｎgandwithoｕtpipｅｌinｉngCTＣPandＵDＰDｐaralleｌａｎdｓeｒiａlconneｃtiｏn42.takeｓforaｓmallｐackeｔtotravelｆromｃliｅnttｏsｅｒverandthenbacktotheclient.ARＤTＢthｒesholｄCRTTDoverhead43．ＴｈedefａultmodeofＨTＴPuses．Anon-persiｓteｎtcｏnnectionwithpｉpeliniｎgBnｏn-persistentconｎｅctionwiｔｈouｔpｉpｅliｎingCｐerｓistenｔconnectiｏｎwitｈpipｅliningDｐeｒsｉsteｎtｃonnｅctioｎwiｔｈoutｐｉｐeｌiniｎg44.InHTＴPreｑuestｍeｓsages，ｔherｅquestlinｅhasthrｅe(cuò)fielｄs，tｈeｒｅaｒｅ.Athｅmｅｔhodfieｌd,theURLfieｌdandtheHTＴＰversionｆieldBtheｍetｈod,thｅconnectionanｄURLfielｄCtheuser－ageｎt,tｈemethｏdandHTTPveｒsionｆieldDtｈeuser-agent，theUＲLandｔｈｅHTTPverｓionfieｌd45.IntｈeｈeaderlinesｏｆHTTＰrｅｑuｅｓtmesｓａge,ifｔhefｉeldofConneｃtiｏｎｉscｌｏse,itspｅcifｉeｓ．ＡｔｈｅhostoｎwhichｏbjeｃtrｅｓidｅｓBwhattypeｏｆtｈeuｓeｒageｎtＣthatｔｈｅbｒowserwaｎtｓtｈｅsｅrvertoclｏsetｈeｃoｎｎectionａｆtersendｉnｇthｅｒeｑuｅstｅdobjeｃtDwhiｃhlanguagecanthebroｗｓerreceive4６.IｎHＴTPrｅｓｐonsemesｓａge,ifthestａｔuscoｄeiｓ40４,itmeanｓ.AreqｕestsucceｅdｅdandtｈeiｎformatｉonisｒeｔuｒnedｉnｔherespｏnseBreｑuestedｏｂjｅcthaｓbeeｎpｅｒmaneｎｔｌymoveｄCtｈerequｅstedHTTPｐｒotocolversioniｓnotsuppｏrtedbytheｓervｅｒDtｈeｒequｅsｔedｄoｃｕmeｎtdoeｓｎotexistonthiｓsｅrver４7.ｉsanetworkenｔiｔythatｓatisfiesHTＴPｒequeｓtsontheｂehalfｏfanｏriginＷeｂｓerver.ApｒoxyｓerｖerBlocalsｅrverCDＮＳseｒverＤＷebserveｒ48.Inthefollowｉnｇfouｒopｔiｏｎｓaboutwｅｂcache,ｗｈiｃhｏneisnoｔcorreｃｔ?ＡAwｅbcａｃheisbｏｔhaｓerveｒandａclienｔatthesａmetｉme.ＢAwｅbcacheispuｒchaseｄandｉnstaｌlｅdbyａnISＰ.CＡwebcａchecaｎｒaisetheresｐｏnsetｉmｅｆoraｃｌieｎtｒeｑuest．ＤAwebcacｈｅｃanredｕｃetｒafｆiconaninstiｔｕtion’sａｃcesslinktｏtheＩnternet.４9．ＴｈeｒeqｕestmessａgeiｎtheｃonｄitionaｌGETmustincludetheｈeaderｌinｅ.ＡLaｓt-ModｉfiedＢLast-ReｆerｅｎｃedCIf-Modifｉeｄ-SiｎｃeDIf–Refeｒｅnced-Sinｃe50.FTPuseｓtwopａraｌｌeｌcoｎnectiｏnstotransferaｆiｌｅ,tｈｅｙarｅ.AＴＣＰaｎdUDPconneｃtｉonBcoｎnecｔｉｏｎwiｔｈpiｐelｉningandwiｔhoｕtpipelininｇCcoｎtrolandataｃonnecｔioｎDclient－sｅrveraｎdｂｒowser-seｒverconneｃtion51．ＩnFTＰcomｍａndｓ,whｉｃｈoneisusedｔoａsｋtheｓeｒvertosｅndｂａｃkaliｓtofaｌｌｆｉlｅsinｔｈecurｒentreｍotｅdirectory?ＡUSＥＲBPASＳCＬIＳTDRETR52.InｔhｅＩｎｔernetmailsysｔｅm,allowuｓerstoread，repｌyto,forｗａrｄ,sａｖeandcoｍposemｅsｓａge.AUｓerａgｅntsBmailserversＣSMTPDTCP5３．ThetwoｋeyMIMＥｈｅadｅrsｆoｒsupportingｍultimｅdiaaｒe.AＣｏｎtent-ＴypeandMIME-VersioｎBＣoｎtent-TｙｐeandConteｎt-Tｒansfeｒ-EnｃodinｇCConteｎt-Transfeｒ-ＥncodiｎｇａnｄＭIＭE-ＶｅｒsioｎDMIME-VerｓｉonandMIME-Type54.ＦorInteｒnetmaｉl,ｔheｍaｉlaｃcessｐrｏtoｃoｌisuｓedto．Atｒａnsfermaｉlfｒomｔhereｃipｉent’smailseｒvｅrｔotｈerecipienｔ’sｕseｒagentＢtｒansfermａiｌfｒｏｍthesendｅr’ｓmaiｌｓｅrverｔotherｅcipienｔ’smａiｌｓerverCtrａnsｌatethemaiｌfｒoｍthesendｅr’smailserｖｅrDtranｓlaｔetｈemailintotherｅciｐｉent’smａiｌserver５5.POP3progresseｓｔhroughｔｈｒeepｈａsｅs,wｈichｔheｙarｅ．Aautｈorizatｉon，ｔrａnslatｉonａndtｒansactiｏnBauthoｒizａt(yī)iｏｎ,traｎslatｉonanｄｕpｄａt(yī)eCauthorｉzation,transaｃtｉｏnanduｐｄateDｔranslatｉon,ｔｒanｓactioｎandupdate56.Ｉnthefollowiｎgfourservices，whｉｃｈｏnecａnｎotｐrovidebyDＮS?AHostaｌiasiｎｇＢMａｉｌseｒｖerａliasiｎｇCｔraｎｓｌａt(yī)eｈostnametoIＰａddreｓsesDtrａnslateＭACａｄdressestoＩPaddｒesｓes57.ＴhereaｒｅthreecｌａsｓｅｓofDNSserveｒｓ,ｔheｒeａrｅ．ArootＤNＳserｖeｒ,top-levelｄoｍaｉnDNSsｅrveraｎdlocａlDNSserveｒBrooｔDNＳserver,toｐ-levelｄoｍainDNSserverandaｕthorｉtatｉveＤNＳservｅｒCroｏｔDNＳserｖer,localDＮSserverａｎdautｈｏritativeDＮSservｅrDroｏtDＮSserveｒ，ｌocaｌＤNSｓerｖerandtop-ｌeｖeｌdoｍainDＮSserver58.IｎthefollowingfｏuropｔionsaｂoutPＯP3，whicｈｏnｅisnｏtcorｒect?AＴheuserａgｅnｔeｍplｏyedonｌythreecoｍmanｄs:List,RetrandQuｉtBＴheserｖerdoesnｏtｃａrrｙsｔaｔeinｆｏrmationaｃrossPＯP3sesｓionsCＴhｅportnuｍberｉs11０DThePOP３pｒｏｔｏcoldoesnｏtprovideanymeansfoｒausertoｃｒｅateremotefolｄeｒsandａssignmessaｇesｔofolｄers.５９.

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message

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MIME-Versioｎ

６６．IftheheaderlineConｎectioniscｌｏse,itmeanｓｔｈatthｅclｉenｔwaｎts.AperｓisｔentｃonｎecｔｉoｎｗithｐiｐelinｉngBpersiｓｔeｎtconnｅctiｏnwｉｔhｏutpｉpeliningCnonｐerｓｉsｔentcoｎnｅctioｎＤｎotconnectiｏn6７.ＩnＨTＴPrequestmｅssaｇe，thｅe(cuò)nｔitybodyisemｐｔywiｔhthｅmethoｄ，buｔiｓｕｓｅdwiｔhｔｈeｍethod.ＡGＥT,PＯSＴBPOST,GETCGＥＴ,HＥADＤPOSＴ,HEＡD6８.InＨTTPresｐoｎseｍｅssａｇｅ，iftheDａt(yī)ｅ:heaｄer;oneinｄｉcatestｈｅtiｍeＦｒｉ.08Aｕg.202312:00:00GMT,theLaｓt-Mｏdifｉed:ｈeａderlｉnecannoｔbｅ.ＡFri.08Ａｕg.202３11:00:00ＧMＴBFri.08Ａug.2０2311:30:0０ＧMTＣFri.08Aug．2０２31２：0０:00GＭTDFrｉ．08Aug.202312:3０:0０GＭT69．Inthefolloｗingfoｕropｔioｎs,wｈichoneisnotｔｈｅparｔoｆｃookieｔechnology?ACookieheadeｒｌｉｎｅsinｔheHＴTＰrespｏnｓemessagｅandrｅqｕｅstmessａｇe．BOnｅcookiehｅａderfｉlｅkeptontheuser’sendsysｔｅｍａndmanagedbytheusｅｒ’ｓbrowseｒ.CAnetｗorkentｉtythaｔsatisｆiesHTTPrequｅstsoｎｔｈebehalfoｆanorｉｇinWｅbserｖｅr.DAbａck-ｅndｄatabａseattheWebｓiｔe７０.On-tｏｐofsｔａt(yī)elessHTTP，ｃａnｂeuseｄtocrｅａt(yī)eausersesｓionlayｅr.AproxｙsｅrverBWebcacｈeCcookｉeＤｓocｋet71.Proceｓsescｏｍmｕnｉｃatewitｈｅａchothｅrｂyreadingfrｏmandｗritiｎgto．AprograｍsBtｈrｅａdsCｓockｅtsDchannｅｌs72.Inthｅfoｌlowingfｏｕｒｏｐtｉonsａｂｏｕtneｔworｋaｒｃｈｉtectｕre,whicｈｏnｅisnｏtcorｒect？AThenetworｋａrchiteｃｔuｒeｉｓfixed．BTｈeneｔｗoｒｋarcｈitｅcturｅpｒoｖｉdesaspｅciｆiｃsｅtｏfservｉcestoapｐｌicaｔioｎ.CＴhｅnetworkarｃhitectuｒeisdesiｇnedｂyappｌiｃatｉondｅveloper．DThｅnetworｋarchiteｃｔuredicｔatesｈoｗthｅａpｐlicationisorgaｎizeｄoverspecialsｅrｖｅｒ.7３.ＩnCｌiｅｎt-Ｓervｅrarｃhitｅctｕre,thecliｅntsvisｉtthｅｓerver’sｔhｒougｈ.Aｃlｉent’ssocｋeｔBｃliｅnt’sＩＰａddreｓsCｓｅrveｒ’ssｏcｋetDｓerver’sIPaｄdress7４.canbetｈoughｔｏfasaprogｒamthａt(yī)ｉsrunninｇwitｈｉneｎdsｙstem.AｐｒocessBthreａdＣsｏckeｔDｃｏnteｘt7５.APIｍeans.AAppliｃａt(yī)iｏnPrograｍＩｎteｒfaceBApplicａｔｉonＰrｏcessInterfacｅCAppellatioｎPrograｍInteｒfａcｅDＡｐpellatｉonPｒｏcｅssInterface7６.Ｏｎｅhostｃａnberunｎiｎｇｍanｙnetｗorkaｐｐlicatiｏns,ｓothesystｅｍａｓsignsthｅｍdｉｆｆｅrenttodｉｓtinguishｅaｃhotｈｅr.ＡＩＰaｄdrｅｓsBportnｕmbｅrCｈｏsｔｎamｅDsectiｏn77.Inthefoｌlｏwｉｎgfourａppｌicatｉｏns,ｗhｉcｈoneisｂothbandwiｔh-ｓｅnsitiｖeaｎｄrequiretｉghttimｉngconstraints?Ａreａl-timeaｕdioBｆiletraｎsferCE-maｉｌＤＷebdｏcuｍentｓ78.TheporｔｎumberｏftｈｅWｅbｓerveris.A25B2０C8０7９.Ｔｈepoｒtnumbｅroｆｔhemaiｌsｅrveris.A２5Ｂ２0C80D8０8080.LｏoktheURL，ｔheｏbｊeｃt’spａｔhｎameis.A．edu.ｃｎB.／ｒjxyＣ/ｒjｘｙ／iｎdex．hｔmｌDindex.html81.EacｈURLｈaｓcｏmponeｎts，thｅyarｅ.Aｔｒanspｏrtpｒotocolandｏbｊｅｃt’spaｔhnameBhｏstｎameando