letsaspweb服务器

aspweb服务器  时间:2021-04-14  阅读:()
MassachusettsInstituteofTechnologyDepartmentofUrbanStudiesandPlanning11.
520:AWorkshoponGeographicInformationSystems11.
188:UrbanPlanningandSocialScienceLaboratoryLecture10:IntroductiontoInternetGISandArcIMSNov.
9,2005,JosephFerreira,Jr.
BasedprimarilyonlecturenotesbyVisitingProf.
Zhong-RenPeng,Fall,2003See:PengandTsou,InternetGIS,2003,JohnWiley,ISBN:0-471-35923-8.
MainTopic:IntroductiontoInternetGISandArcIMSIntroductiontoInternetGISStateoftheArtofInternetGISIntroductiontoArcIMSTheRoadMapofGISStand-aloneGISProgramsMainframe-basedmonolithicGISprogramsDesktopGISprogramsLimitedornocommunicationwithothercomputers(otherthantransparentlyvia,forexample,useofanetworkfileserver)ProgramsneedtorunonthemainframeorPCwheretheprogramresidesUsersneedaccesstothatmachineviaaloginordumbterminalsession.
Examples:earlyArc/Infoinstalledonastand-alonemainframeorPC.
LAN-basedGISProgramsGISinstalledononeormoremachinesonaLocalAreaNetwork(LAN)GISprogramsrunonlocalmachinesbutcansharedataandprintingfacilitiesfromthedataserver,orGISprogramsrunonaserver,usercanaccessitfromanymachineinsidetheLAN.
TypicalClient/Serverarchitecture.
Examples:MostcurrentGISprograms.
LimitationsofStand-AloneandLAN-basedGISProgramsDifficultforuseroutsidetheLANtoaccess.
DifficulttodirectlyaccessdatathatareavailableoutsidetheLAN.
LimitedGISusers.
Difficulttomange,updateandextend.
WhatisInternetGISInternetGISisanetwork-centricGIStoolthatusestheInternetasaprimarymeansofprovidingaccesstothefunctionality(e.
g.
,analysistools,mappingcapability)ofGISandtothespatialdataandotherdataneededforvariousGISapplications.
InternetGISisanintegratedclient/server,andWeb/Serverapplication.
InternetGIStypicallyusesaWebbrowserasclient.
InternetGIScanbeviewedasadistributed,object-orientedsystem.
InternetGISisportableandcross-platform.
InternetGISvsWebGISWhat'sthedifferencebetweentheInternetandtheWorldWideWebInternetreferstotheinter-connectedcomputernetwork,--infrastructure.
WebisoneofmanyapplicationsthatarebasedontheInternet.
ThetermInternetGISfocusestheuseofasuiteofInternettechnologies,notonlytheWeb.
InternetGISthushasmorelongevityandisapreferredterm.
FeaturesofInternetGISWideaccessibility,usersfromtheworldcanaccessGISdataandanalysistoolsovertheInternet.
NoGISsoftwareisrequiredtoinstalllocally.
TakesadvantageofthefriendlygraphicuserinterfacethatisprovidedbytheWorldWideWeb.
UserscandirectlymanipulatemapsandGISdataovertheWeb.
Internet-awareGISsoftwarecanaccessremotedataanywhereontheInternet.
InternetGIScaneasilyincorporateup-to-date,real-timeinformationBasicComponentsoftheInternetGISInternetGIS:StateoftheArtStaticMappublishingStaticWebMappingInteractiveWebMappingClient-sidePlug-insandHelperProgramGISActiveXControlsJava-basedInternetGISDistributedGeographicInformationServicesServer-SideandClient-SideInternetGISServer-SideInternetGISHTMLtoGISserverviaCGI(CommonGatewayInterface)scriptClient-SideInternetGISClient-sidePlug-insandHelperProgramGISActiveXControlsJava-basedInternetGISHybridofserver-andclient-sideInternetGISStaticMappublishingInsertMapimagesinatextfileontheWeb.
NotaGIS.
StaticWebMappingHowdoesitworkCommonGatewayInterfaceWheninformationiscollectedbyabrowseritissenttoaHyperTextTransferProtocol(HTTP)serverspecifiedintheHTMLform,andthatserverstartsaprogram,alsospecifiedintheHTMLform,thatcanprocessthecollectedinformation.
Suchprogramsareknownas"CommonGatewayInterface"programs,orCGIscripts(E.
O.
Johnson).
CGIisasimpleinterfacethatlinksWebbrowser,serverandotherexternalprograms.
CGIorDynamicLinkLibrary(DLL)hasthreefunctions:ItreceivesuserinputsandparsesthemintoparametersofvariablestobeusedinGISprograms.
ItletsWebserversrunotherGISprograms.
Itinterpretsoutputandsendsbacktobrowsers.
AdvantagesofStaticWebMappingA"thin"client(e.
g.
,alldataprocessingisdoneontheserver,whiletheclientisusedonlyfordisplayanduserinput).
TakesfulladvantageofallGISsoftwarefunctionalityattheserver.
UbiquitouslyaccessibleovertheInternet.
CanhandlelargedatabasetoservespatialqueriesDrawbacksofStaticWebMappingEveryuserrequesthastogothroughtheInternettoactivateaCGIscripteverytime.
CreatesheavytrafficovertheInternet.
Operationisslow,becauseeverycommand(evenverysimpleoneslikezoomandpan)hastobeoperatedontheGISserver.
Mapsarestaticimages.
Usercannotdrawaboxoracircleorselectpolygonsonthemapimages.
ExamplesofStaticWebMappingVISAInternationalATMlocator(http://www.
visa.
com/)ESRI'sMapObjectsInternetMapServer(http://metro-trip.
ci.
waukesha.
wi.
us/waukesha/)MapQuest(http://www.
mapquest.
com/)InteractiveWebMapping(Client-SideInternetGIS)InteractiveWebMappingprogramsallowtheusertomanipulateGISdataandconductGISanalysisattheclient/userside,including:GISPlug-InsandHelperProgramsGISJavaAppletsGISActiveXControlsGISPlug-InsorHelperProgramsGISplug-insaresoftwareexecutablesthatrunonthebrowserandinterprettheGISdatareceivedfromtheserver.
GISplug-insareusedinextendingthebrowsertoprocessGISdata.
WhileGISplug-insaresmallapplications,GIShelperprogramscanbelargeGISapplicationsorexistingGISsoftwarethatislocatedintheuser'slocalmachine.
HowDoGISPlug-InsWorkPartitionPointsforGISPlug-InExamplesofGISPlug-insAutodesk:MapGuide(http://www.
mapguide.
com/)GeoMediaWebMap(forNetscapebrowser)AdvantagesofGISPlug-InsGISplug-insenableWebbrowsertointeractwithGISdata.
SomeGISfunctions(i.
e.
,zoom,pan,query)canbeconductedbytheplug-ins,soitcanreducetrafficontheInternet.
GISplug-inscanfetchdatafromtheserverondemand.
Plug-insareeasytocontrolandarenotdistributedwithbrowsers.
DrawbacksofGISPlug-InsPlug-insarenotplatform-independent.
TheGISvendorhastocreatedifferentplug-insfordifferentoperatingsystems(Unix,PC).
Usershavetodownloaddifferentplug-insfromdifferentGISservers.
GISplug-insandhelperprogramshavetobeinstalledintheuser'smachine.
Securityconcernsmakeusershesitanttodownloadplug-ins.
GISAppletsGISappletsareexecutablecodethataredownloadedfromtheserverandexecutedonthebrowserclientatruntime.
Javaappletsuseanobject-orientedlanguagedesignedtoworkonavirtualmachineandincludingfunctionalitythatisusefulfortheinterfacedesignofGISmappingandanalysisfunctions.
Javaappletsareinterpretedlocallyviatoolsthatareembeddedinthemostcommonbrowsers.
Java-BasedInternetGISHowdoesitworkExamplesofJava-BasedInternetGISMapXtremefromMapInfo(http://www.
mapinfo.
com/)Googlemaps(http://maps.
google.
com/)(usingAJAX:asynchronousjavascripttechnologyandXML:http://java.
sun.
com/developer/technicalArticles/J2EE/AJAX)ArcIMSfromESRI.
PartitionPointforGISAppletsTheappletmodelmovesthepartitioningpointfurthertotheright.
Appletgivestheapplicationdesigner/developertheflexibilitytodeterminewheretosplittheapplication.
Forexample,aWebservermaysupplydifferentappletsdependingonthespeedoftheconnectionbetweenitanditsclients.
AdvantagesofJava-basedInternetGISJava'sbytecodeisplatform-neutral,soitcanruninanymachinewithoutmodification.
Forvendorsanddevelopers,itmeanslargerpotentialmarketandtheeliminationof"softwareporting.
"Forusers,itmeanslowercostandgreaterinteroperabilityamongcomponents.
Javaappletisrunonlocalmachine,minimizingthrough-nettraffic,andmakingbetteruseoflocalcomputingresources.
Javaappletsaremoreflexibleincreatinganddisplayinggraphicsandmaps.
Javaappletsaredownloadedfromtheserveratruntimeandwilldisappearwhentheuserquitstheapplication.
Javaismoresecure,becauseappletsrunontheJVMontheuser'slocaldevice.
Javaappletshavenoaccesstolocalsystem.
DrawbacksofJavaAppletIttakessometimetoinitiallydownloadapplets.
Thisisespeciallyproblematicforslowconnections(e.
g.
,viadialupmodems).
ItneedsJava-enabledWebbrowserforJavaappletstofunction.
Itcannotaccesslocalfilesanddata(duetosecuritylimitationsofJavatools).
JavabasedWebGIScannotselectobjectsbyradiusorselectobjectfrommultiplethemes(E.
O.
Johnson).
JavaPlug-InOldJavaappletreliesonthewebbrowser'sdefaultvirtualmachine.
JavaPlug-insoftwareenablesenterprisecustomerstodirectappletsorJavaBeansontheirintranetwebpagestorunusingSun'sJava2RuntimeEnvironment,StandardEdition(JRE).
TheJavaplug-inallowsredistributionofbothstandaloneJavatechnology-basedapplicationsandbrowser-basedapplets(http://java.
sun.
com/products/plugin/).
GISActiveXControlsAnActiveXcontrolisapieceofexecutablecodethatcanrunonWindowsplatforms.
ActiveXcontrolsconformtotheCOM(ComponentObjectModel)standard.
Theyareloadedandexecutedinsideacontainer(InternetExplorer).
HowDoGISActiveXControlsWorkPartitionPointforActiveXControlsSameasforJavaAppletExampleofGISActiveXControlsIntergraph'sGeoMediaWebMapServer(http://imgs.
intergraph.
com/gmwm/)MapGuide(www.
mapguide.
com)AdvantagesofGISActiveXControlsOffersbetterperformance,becausetheyarecompiledtothenativeexecutableformat.
Takesfulladvantageoflocalmachineresourcesandplatformfunctionality(e.
g.
files,memory,hardwareandsoftwaresystemcontrols)unavailabletoaJavaapplet.
Canaccesstolocaldata.
AdvantagesofGISControlsSomeGISfunctions(i.
e.
,zoom,pan,query)canbeconductedbytheGIScontrols.
GIScontrolscanfetchdatafromtheserverondemand.
GIScontrolscancommunicatewithotherActiveXcontrolsanddatalocallyaswellasremotelyaslongastheyconformtotheCOMstandard.
DrawbacksofGISActiveXControlsPortability:platformdependent,differentActiveXcontrolsneedtobecreatedfordifferentplatforms.
UsershavetodownloaddifferentGIScontrolsfromdifferentGISvendors,suchasGIScontrolsfromESRI,Intergraph,etc.
NotallbrowserssupportActiveXcontrols.
Forexample,Netscapeneedsaplug-intorunActiveXcontrols.
GIScontrolshavetobeinstalledintheuser'smachineandleadtoa"fat"client.
Safety:BecauseActiveXcontrolshavefullaccesstoplatformservices,theycandogreatdamagetoalocalsystem.
Safetysolution:Useverificationapproachtoverifyifacontrolissuppliedbyatrustedsource.
Theassumptionisthatifitissuppliedbyatrustedsource,itshouldbesafetouse.
SafetyConcernsofActiveXControlsProblemswiththeverificationapproachTobesafe,userswouldhavetorejectallActiveXcontrolsnotsignedbyanauthority.
EveniftheusercanverifytheActiveXcontrolcomesfromareliablesource,thereisstillnowaytotellifexecutingthecontrolwillcausedamage.
DataStreamingontheInternetStreamingsubsetofdatatotheclient.
Fulldatasetstoredinthedataserver.
Theclienthasthecapabilitytoreplicateandcachedataontheclientside.
Thepresentation(displayandvisualization)andlogiccomponents(maprendering)oftheapplicationresideontheclientsideinordertointelligentlydisplaythedata.
Example:GoogleEarth'sclient:(http://earth.
google.
com)PartitionPointforDataStreamingAdvantagesofInteractiveWebMappingInteractiveWebmappingenablesWebbrowsertointeractwithvectordataratherthanstaticmapimages.
SomeGISfunctions(i.
e.
,zoom,pan,query)canbeconductedbytheclient-sideprograms,soitcanreducetrafficontheInternet.
Client-Sideprogramscanfetchdatafromtheserveratruntime.
DrawbacksofInteractiveWebmappingIttakessometimetoinitiallydownloadclient-sideInternetGISprograms.
Someclient-sideInternetGISprogramsarenotplatform-independent.
LimitedfunctionalityDifficulttohandleverylargedatabase,sincethetransportoflargeamountsofdataovertheInternetisslow.
IntroductiontoArcIMSArcIMSArchitectureArcIMSComponentsArcIMSClientViewersHTML/DHTMLViewerwrittenusingHTML,DHTML(dynamicHTML),andJavaScript.
AthinclientthatonlysupportsmapimagesontheWebbrowser.
Onlyoneimagecanbedisplayedatatime.
ColdFusionandActiveXViewersSimilartoHTML/DHTMLViewer,butthinnerJavaViewersupportbothImageandFeaturestreamingArcIMSBusinessLogicTierArcIMSWebServerReceivesrequestfromWebClient.
CommunicateswiththeWebclient(browser)throughHTTP.
ForwardsclientrequesttoApplicationServerviaApplicationServerConnector.
CommunicateswithApplicationServerthrougheitheraJavaServlet,orColdFusionortheActiveServerPages(ASP).
ApplicationServerConnectorTheconnectorsprovideacommunicationchannelbetweenaWebServerorathirdpartyapplicationserverandtheApplicationServer.
TheconnectorsestablishasocketconnectionwiththeApplicationServerforeachrequest.
Oncethecommunicationchannelisestablished,requestsaresenttoandresponsesarereceivedfromtheApplicationServer.
ArcIMSApplicationServerManagesloadandassignstaskstospatialservers.
ServesasabookkeeperforkeepingtrackofwhichMapServicesarerunningonwhichArcIMSSpatialServers.
AllocatesanincomingrequesttotheappropriateSpatialServer.
TheApplicationServercancommunicatewithMultipleWebServers.
ArcIMSSpatialServerThisisthebackboneofArcIMS.
Itcanproducemaps,accessdata,andbundlemapsintoanappropriateformatbasedontheuserrequests.
Itcontainsseveralsupportingcomponents:Weblink,theXMLparser,andtheDataAccessManager.
WeblinkisthecommunicationgatewaybetweentheArcIMSApplicationServerandtheSpatialServer.
TheXMLparserisusedforparsingArcXMLrequests.
TheDataAccessManagerprovidesalinkbetweentheSpatialServerandanydatasources.
FunctionsofArcIMSSpatialServerImagerendering–generatesmapimagesFeaturestreaming–streamsfeaturedataGeocoding–locatesaddressesonmapsQuery–returnsassociateddataforspatialandtabularqueriesDataextraction–returnsdatainShapefileformattotheclientArcIMSVirtualServerItisagroupingofoneormoreSpatialServers;itisnotaphysicalentity.
ItiscreatedtobettermanagedistributedSpatialServers.
ToimproveservicereliabilityandscalabilityFiveVirtualServers:ImageServer,FeatureServer,QueryServer,GeocodeServer,andExtractServer.
FeatureStreaming(Javaclientsonly)StreamsvectorsandattributesLocallycachedCompressedbinary/XMLJavaclientsLocalgeoprocessingBuffer,MapTips,Query,MapSymbolization,.
.
.
InternetFeatureStreamingThinClientvs.
ThickerClientThinClient-ImageStreamingServer-sideprocessingGIF/JPEG/PNGimagesFasterLoadingThickerClient-FeatureStreaming(javaonly)Vector/Raster/AttributeDataMoreClient-sideFunctionsRobustDevelopmentEnvironmentExamples:(howdotheysplitclient/servertasks,whatprotocolsareused,.
.
.
)RunningArcMaponthe37-312labmachinesRunningArcGISonMIT'sCitrixserverUsingtheMITOrthoServerviaabrowser(http://ortho.
mit.
edu)UsingtheMITOrthoToolsbuttonfromwithinArcMapRunningGoogleEarth(http://earth.
google.
com)TheMassGISdataviewer:Oliver(http://maps.
massgis.
state.
ma.
us/massgis_viewer/index.
htm)ShowninlabnextMonday:oArcIMSserverfor(optional)Lab#9(runningonaLinuxPC)o'IntelligentMiddleware'project:webservicesusingMinnesotaMapServer+PostgreSQLandPostGIS(runningonaLinuxPC)WrittenbyZhong-RenPeng,Fall,2003Lastmodified9November2005.
[jf]

Megalayer新加坡服务器国际带宽线路测评

前几天有关注到Megalayer云服务器提供商有打算在月底的时候新增新加坡机房,这个是继美国、中国香港、菲律宾之外的第四个机房。也有工单询问到官方,新加坡机房有包括CN2国内优化线路和国际带宽,CN2优化线路应该是和菲律宾差不多的。如果我们追求速度和稳定性的中文业务,建议还是选择CN2优化带宽的香港服务器。这里有要到Megalayer新加坡服务器国际带宽的测试服务器,E3-1230配置20M国际带...

香港ceranetworks(69元/月) 2核2G 50G硬盘 20M 50M 100M 不限流量

香港ceranetworks提速啦是成立于2012年的十分老牌的一个商家这次给大家评测的是 香港ceranetworks 8核16G 100M 这款产品 提速啦老板真的是豪气每次都给高配我测试 不像别的商家每次就给1核1G,废话不多说开始跑脚本。香港ceranetworks 2核2G 50G硬盘20M 69元/月30M 99元/月50M 219元/月100M 519元/月香港ceranetwork...

弘速云香港VPSVPS线路有CN2+BGP、CN2 GIA,KVM虚拟化架构,裸金属月付564元

弘速云怎么样?弘速云是创建于2021年的品牌,运营该品牌的公司HOSU LIMITED(中文名称弘速科技有限公司)公司成立于2021年国内公司注册于2019年。HOSU LIMITED主要从事出售香港vps、美国VPS、香港独立服务器、香港站群服务器等,目前在售VPS线路有CN2+BGP、CN2 GIA,该公司旗下产品均采用KVM虚拟化架构。可联系商家代安装iso系统。点击进入:弘速云官方网站地址...

aspweb服务器为你推荐
企业推广推广专员一般每天要做哪些工作360退出北京时间北京时间校准显示时间重庆电信dns重庆电信 路由器连接另一个电脑,本地连接的IP是多少,?DNS首选,备用 服务器是多少?flashfxp注册码谁知道 FlashFXP.rar的注册码?瞄准的拼音瞄怎么读,瞄的组词,瞄的读音,瞄的笔顺,瞄的意思3g手机有哪些3G手机???佛山海虹广东海虹药通电子商务有限公司怎么样?联系我们代码如何查询统一社会信用代码账号通谁知道帐号通怎么解 我的号被盗号的帮了oscommercewedopay的通道怎么样?
虚拟主机管理系统 虚拟主机测评 域名大全 广东vps 本网站服务器在美国维护 cpanel主机 免费博客空间 typecho ev证书 一点优惠网 免费个人空间申请 789电视网 91vps 什么是服务器托管 idc查询 美国独立日 便宜空间 国外的代理服务器 lamp兄弟连 lamp的音标 更多