计算机专业外文翻译Word格式文档下载.docx

计算机专业外文翻译Word格式文档下载.docx

《计算机专业外文翻译Word格式文档下载.docx》由会员分享，可在线阅读，更多相关《计算机专业外文翻译Word格式文档下载.docx（34页珍藏版）》请在冰点文库上搜索。

centers,andWebServices.Wetermsuchanetworkof

nodesasacloud.Anapplicationbasedonsuchcloudsis

takenasacloudapplication.

Thisparadigmisincreasinglypopularintheindustry,

whereindustrialleaderssuchasMicrosoft[26],Google

[2],andIBM[5]stronglypromotetheparadigminrecent

years.Anearlyattempttoformulatecloudcomputing

datesbacktoatleast1997[8].However,toourbest

knowledge,theadoptionandpromotionofcloud

computinghasbeenslowuntil2007[9].

Weobservethatthehistoryofearlyindustrial

adoptionsofcloudcomputingsharesomecommon

milestoneswiththatofservicecomputing[4].For

example,ittookservicecomputing[27]alongtime（ten

yearsorso）toreceiveworldwidesupportfromleading

companieslikeIBM,Microsoft[25],BEA,andOracle.

Similarly,ithasbeenmanyyearssincetheearly

formalizationeffort[8]towardcloudcomputing.

Besides,thewideadoptionofacomputingparadigm

usuallydependshighlyonthematurityofsupporting

technologiesandindustryrecognitions.Servicecomputing

hasbecomemuchmorepopularsincethesuccessof

Webservices,althoughaWebserviceisonlyoneofthe

technologiestofulfillthenotionofserviceorientation[4].

Similarly,thedistributedcomputingcommunityhas

pointedoutthatmanydistributedcomputingtechniques

forcloudcomputinghavebeenmature[7][10][11].Many

companiessuchasDellandIBMhavebeguntoship

cloudcomputingmachines[5][10].

Lastbutnottheleast,ineitherservicecomputingor

cloudcomputing,researchdevelopmentslagbehind

industrialadoptions.Forinstance,COSCON,aleading

internationalcontainershipper,hasasuccessfuladoption

ofservicecomputing.Itsuccessfullyusedservice-oriented

architecturetoimprovethebusinessresponsibilityto

customersin2004[3].Yet,researchstudiesinserviceoriented

architecturefromthesoftwareengineering

community[19]arestillinadequate.

DespiteoursurveyovertheInternet,toourbest

knowledge,therearefewarticlestopinpointresearch

*©

2008IEEE.Thismaterialispresentedtoensuretimelydissemination

ofscholarlyandtechnicalwork.Personaluseofthismaterialis

permitted.Copyrightandallrightsthereinareretainedbyauthorsorby

othercopyrightholders.Allpersonscopyingthisinformationare

expectedtoadheretothetermsandconstraintsinvokedbyeach

author’scopyright.Inmostcases,theseworksmaynotbereposted

withouttheexplicitpermissionofthecopyrightholder.Permissionto

reprint/republishthismaterialforadvertisingorpromotionalpurposes

orforcreatingnewcollectiveworksforresaleorredistributionto

serversorlists,ortoreuseanycopyrightedcomponentofthisworkin

otherworksmustbeobtainedfromtheIEEE.

†ThisresearchissupportedinpartbytheGeneralResearchFundofthe

ResearchGrantCouncilofHongKong（projectnos.111107,717308,

and717506）.

‡Correspondingauthor.

2

issuesincloudcomputing.Thiswouldslowdownthe

nextresearchadvances.Wewillalleviatethisproblemin

thepresentpaper.

Inthispaper,weusetheclassiccomputerarchitecture

model[15]toprovideaqualitativecomparisonframework

tocomparecloudcomputingwithpervasivecomputing

andservicecomputing.Thequalitativecomparison

frameworkincludesthreefeatures:

input-output（I/O）,

storage,andcalculation.Foreachfeature,wedrawthe

comparisonusingmultiplecharacteristics.Throughsuch

comparisons,weidentifytheconnectionsbetweencloud

computingandtheothertwocomputingparadigmsfrom

theperspectiveofsoftwareengineering.Basedonthe

connections,wedrawupafewresearchissuesanddiscuss

theminthepapertopromotefutureexploration.

Themaincontributionofthepaperistwofold:

（i）To

ourbestknowledge,weprovidethefirstqualitative

comparisononcloudcomputing,servicecomputing,and

pervasivecomputing.（ii）Wepresentaseriesofresearch

issuesincloudcomputingontopofthecomparison

framework.Theseissuespromotefutureexplorations.

Therestofthepaperisorganizedasfollows:

Section2

presentsthepreliminariesofcloudcomputing,service

computing,andpervasivecomputing.Section3introduces

ourqualitativeframeworktocomparetheabove

threecomputingparadigmsandpresentoureffortsto

identifyresearchissuesincloudcomputing.Finally,we

reviewrelatedworkinSection4anddrawaconclusionin

Section5.

2.Preliminaries

Thissectionreviewsthepreliminariesofcloud

computing,servicecomputing,andpervasivecomputing.

2.1.Cloudcomputing

AswehaveintroducedinSection1,acomputingcloud

isamassivenetworkofnodes.Thus,scalabilityshouldbe

aqualityfeatureofthecomputingcloud.Ithasatleast

twodimensions,namelyhorizontalcloudscalabilityand

verticalcloudscalability（adaptedfrom[9]）.

􀁺

Horizontalcloudscalabilityistheabilitytoconnect

andintegratemultiplecloudstoworkasonelogical

cloud.Forinstance,acloudprovidingcalculation

services（calculationcloud）canaccessacloud

providingstorageservices（storagecloud）tokeep

intermediateresults.Twocalculationcloudscanalso

integrateintoalargercalculationcloud.

Verticalcloudscalabilityistheabilitytoimprovethe

capacityofacloudbyenhancingindividualexisting

nodesinthecloud（suchasprovidingaserverwith

morephysicalmemory）orimprovingthebandwidth

thatconnectstwonodes.Inaddition,tomeetincreasing

marketdemand,anodecanbegraduallyupgradedfrom

asinglepowermachinetoadatacenter.

Scalabilityshouldbetransparenttousers.Forinstance,

usersmaystoretheirdatainthecloudwithouttheneedto

knowwhereitkeepsthedataorhowitaccessesthedata.

Forsimplicity,wewillrefertohorizontalandvertical

cloudscalability,respectively,ashorizontalscalability

andverticalscalabilityinthispaper.

2.2.Servicecomputing

Servicecomputing（orservice-orientedcomputing）is

anemergingparadigmtomodel,create,operate,and

managebusinessservices.Inthisparadigm,services

publishthemselvesinpublicregistries,discoverpeer

services,andbindtothelatterservicestoformservice

compositionsusingstandardizedprotocols[6].Tocreatea

servicecomposition,engineersmayuseaspecification,

suchasWS-BPEL[30],tomodelthecollaborativeneed

inworkflows.Tocarryoutindividualworkflowsteps,

softwaredevelopersmayuseWebservices,themost

popularwaytofulfillservice-orientedarchitectureinthe

industry.Asetofservice-orientedapplicationsoverthe

Webservicesthuscreatesanetworkofservices.

ServiceServiceRegistry

RegisterService

toRegistry

DiscoverService

fromaregistry

BindServiceAssociateService

Figure1.Service-orientednetwork[18].

Webrieflydescribeaservice-orientednetwork[18]to

facilitatethecomparisonintherestofthepaper.An

elementinsuchanetworkisaserviceregistry,service

consumer,orserviceprovider.Aserviceprovider

registersitselfinaserviceregistry.Aserviceconsumer

firstdiscoverstheservicefromaregistry,andthenbinds

totheservice.Aserviceprovidermayregisteritselfto

morethanoneregistry.Aregistrymayalsoassociateits

registeredservicestootherregistries,andactsasaservice

itself.Suchatreatmentonaregistryprovidesageneric

viewamongelementsinservice-orientedmodeling.

2.3.Pervasivecomputing

Pervasivecomputing（orubiquitouscomputing）[23][24]

isanotheremergingcomputingparadigm.Software（often

referredaspervasivesoftware）canbeembeddedina

constantlychangingcomputingenvironment.Therefore,

pervasivesoftwareusersdonotneedtobeconcerned

abouthowtoadjustthesoftwaretoadapttothe

surroundingcomputingenvironment.Awell-developed

environmentwillenableuserstousepervasivesoftware

everywherewithoutextraeffort.

Tounderstandandreacttoauser,applicationsuse

environmentalfeatures,knownascontexts,extensively.

Sensorscancapturethesecontexts.Toallowubiquitous

3

supporttoendusers,smartsensorsareplacedaround

userstopreservedifferentinformation,suchasthe

locations,contexts,anduser-relevantdata.

Figure2showsapervasivecomputingexample.

Sensors,mobilephonesandPDAs,desktopcomputer,and

serversareinterconnectedlogicallytoformanapplication.

SupposeanomadicuseratthetopleftcornerofFigure2

movesfromusingalapt