标准化是网路技术演进的主轴

1、TopicWeb Services ArchitectureandTechnical OverviewWeb Computing LabComputer Science Information Engineering DepartmentFu Jen Catholic UniversityOutlineEvolution of Internet TechnologyArchitectureOverview of Web Services TechnologyConceptual Web Service StackIf You Only Remember Three ThingsIntegrat

2、ionWeb Services Description LanguageSimple Object Access ProtocolService DiscoveryUniversal Description Discovery and Integration Summary 標準化是網路技術演進的主軸SOAP over 是 Middleware 技術演進之必然1978Internet ftpsmtpgopher1992Mosaic1994Netscape19892002Web Services1996Servlet1998EJB1999JSP的黃金歲月Web Application是 時代的技

3、術支撐Middleware技術本钱 = 通讯 + 資料 + 格式技術門檻驟降， 成為全民運動JSP主導作業流程，承載 Business ModelEJB 主掌資料存取，是中心價值但競爭優勢何在?InternetPresentationLayerJSPBusiness LogicgetPrice()getName()getTime()getMsg()DBApplication Server HTMLBrowserWeb Application是 時代的技術支撐Middleware技術本钱 = 通讯 + 資料 + 格式EJB 的表現 被 JSP 所局限EJB 的功能無法進一步的發揮JSP 無法符合

4、不同的客戶需求市場需求改變，JSP也必須跟著改寫Application ServerInternetPresentationLayerJSPBusiness LogicgetPrice()getName()getTime()getMsg()DB HTMLBrowser? 假设市場需求進化到AboveNet?Middleware技術本钱 = 通讯 + 資料 + 格式Servlet 自訂格式，讓 EJB 價值多元呈現Application ServerInternetJSPBusiness LogicgetPrice()getName()getTime()getMsg()DBVB ClientSe

5、rvletServlet 假设市場需求進化到AboveNet?Middleware技術本钱 = 通讯 + 資料 + 格式Servlet 自訂格式，讓 EJB 價值多元呈現Application Server但是，customize 的本钱高Client : 各式資料格式，莫衷一是，無所遵照InternetJSPBusiness LogicgetPrice()getName()getTime()getMsg()DBVB ClientServletServlet? 假设市場需求進化到AboveNet?Middleware技術本钱 = 通讯 + 資料 + 格式Servlet 自訂格式，讓 EJB 價

6、值多元呈現Application Server但是，customize 的本钱高Client : 各式資料格式，莫衷一是，無所遵照Server : Servlet流程代工，難以重複利用InternetJSPBusiness LogicgetPrice()getName()getTime()getMsg()DBVB ClientServletServlet?Web Services是 Middleware 技術演進之必然Middleware技術本钱 = 通讯 + 資料 + 格式Servlet 自訂格式，讓 EJB 價值多元呈現但是，customize 的本钱高Client : 各式資料格式，莫衷

7、一是，無所遵照Server : Servlet流程代工，難以重複利用InternetJSPBusiness LogicgetPrice()getName()getTime()getMsg()DBApplication ServerVB ClientServletServlet?Price()Name()Time()Msg()Web Services是 Middleware 技術演進之必然Middleware技術本钱 = 通讯 + 資料 + 格式流程設計主導權由 server 端移轉至 client 端Application ServerClient 端請求service服務及其回應，均藉由so

8、ap/http標準化以降低開發本钱InternetJSPBusiness LogicgetPrice()getName()getTime()getMsg()DBVB ClientServletServletPrice()Name()Time()Msg()SOAPProxyWeb ServicesRuntimeSOAPRouterWeb ServicesRuntimeSOAPProxyWeb Services是 Middleware 技術演進之必然Middleware技術本钱 = 通讯 + 資料 + 格式Services的規格由WSDL描画之且讓 UDDI 构成結構化服務描画聚落Applicat

9、ion ServerClient 藉由 WSDL 知曉 Server 提供的服務，並藉以開發Web Service應用InternetJSPBusiness LogicgetPrice()getName()getTime()getMsg()DBVB ClientServletServletPrice()Name()Time()Msg()SOAPProxyWeb ServicesRuntimeSOAPRouterWeb ServicesRuntimeSOAPProxyWSDLWSDLUDDIWSDLWeb Services 技術架構誕生ComposedInternetJSPBusiness Lo

10、gicgetPrice()getName()getTime()getMsg()DBApplication ServerVarious ClientsServletServletWeb ServicesRuntimeSOAPRouterWSDLUDDIDescribedPublishedFoundBoundInvokedModularWeb Services 技術架構誕生Web Service = + XML + StandardContainer: J2EE 1.3JAXPJAXBJAC-RPCJAXMJAXRJSR110JavaStandards: W3CXMLXML SchemaWSDLS

11、OAPUDDIebXMLArchitectureOverview of Web Services TechnologyService Provider:Construct servicesWeb Services interface (EAR)PublishService Requestor:Construct request servicesDiscover and download WSDL documents.Web Services interface (proxy)CommunicationBy using SOAPOverview of Web Services Technolog

12、yServiceProviderServiceRequestorEARPROXYServicesRegistryPublishFindWSDLDoc.DownloadBindRequestInvokeresultReturnResponseSOAP Messages(Implementation Definition)Overview of Web Services TechnologyServiceProviderServiceRequestorEARPROXYWSDLDoc.DownloadRequestInvokeresultReturnResponseSOAP MessagesServ

13、icesRegistryWeb ServicesStandardOverview of Web Services TechnologyServiceProviderServiceRequestorEARPROXYServicesRegistryWSDLDoc.DownloadBindRequestInvokeresultReturnResponseSOAP MessagesDepend onPlatformOverview of Web Services TechnologyServiceProviderServiceRequestorEARPROXYServicesRegistryWSDLD

14、oc.DownloadRequestInvokeresultReturnResponseSOAP MessagesGeneratedby ToolsConceptual Web Services StackDefinition of Stack Layers Network Internet-standards-based transport , HTTPS FTP SMTP Optimized intra-organization protocols Network choice should be based on Where service will be accessed from D

15、egree of interoperability required Existing network and messaging infrastructure Degree of reliability and security requiredDefinition of Stack Layers XML-Based Messaging Messages are sent as XML documents conformant to well known or published XML Schemas The messaging infrastructure will use SOAP S

16、OAP is the simple, standardized enveloping mechanism for communicating documentcentric messages and remote procedure calls using XML SOAP defines a standard mechanism to incorporate orthogonal extensions to the message using SOAP headersDefinition of Stack Layers Service Description Service Interfac

17、e Definition Specification of logical interface and bindings WSDL provides all IDL capabilitiesDefinition of Stack Layers Service Description Service Implementation Definition Defines network location, protocols, security requirements and other attributes specific to a particular instance of a servi

18、ce endpoint for a bindingDefinition of Stack Layers Complete Service Description Business Context, Taxonomies, Keywords: UDDI Endpoint capabilities and policies Choreography among services and businessesDefinition of Stack Layers Service Publication Make the Service Description available Create the

19、nonfunctional service description Taxonomy, ownership, business name, business type, various keywords for discovery easier Endpoint details and requirements Where the description is published can vary: Directed-, diskette, . Web Service Inspection Language (WSIL) UDDIPrivate or Universal Business Re

20、gistryDefinition of Stack Layers Service Discovery Static Services found and bound to at development time Found in file system, URL, or services directory Tools browse/search/generate skeletons proxies Dynamic Bind interface during development and Find service implementation endpoint at runtime Inte

21、rface and Endpoint found and bound at runtime Found at URL or services directory UDDI defines a searchable services directoryDefinition of Stack Layers Service Flows Services as activities in work flows Flows of services, potentially between partners Services as wrappers for exposed business process

22、es Service composition This is an emerging paradigm IBM has published WSFL Microsoft has published XLangDefinition of Stack Layers Quality of Service Network Level: reliable messaging Service Description Level: Implementation level Ex. Transactional, secure Interface level Ex. Tolerable response tim

23、es Provided by WSDL and potentially other definitions (potentially based on ebXML Partner Agreements type of information) Publication/Discovery: highly available UDDI nodeDefinition of Stack Layers Management Means: Information: Identification, Configuration Metrics: Performance Control: Operations,

24、 Configuration By Management System for: Web Services Infrastructure Each enterprise responsible for managing own infrastructure Enterprises will need to expose management interfaces for use by business partners: status, query, cancelDefinition of Stack Layers Security Requirements: Confidentiality

25、Authorization Data Integrity Proof of Origin Non-Repudiation Secure transport is not enough: End to End compromised by intermediaries Middleware independence Transport independence Asynchronous multi hop messagesDefinition of Stack Layers Security Network HTTPS, SSL, current network technologies XML

26、 Messaging Basic Auth in SOAP header XML Digital Signature Support trusted third-party authentication Service Description Security capabilities and requirements Publication/Discovery Trusted registry, trusted access (same issues)值得關注的後續發展主題Security standards and JSRsReliable Messaging exactly once d

27、eliveryEnabling services infrastructure turned servicesQuality of Service living up to expectationIntegrationSystem logic redesignResourceSystemLogicgetTime()getName()PresentationHTMLJSPASPApplicationPresentationSystemLogicResourcePresentationSystemLogicResourcePresentationSystemLogicResourceWebServ

28、icesIntegration (Cont.)IntegrationTech DataTech DataCompany ACompany BEmployeeEmployeeWeb ServicesWeb Services Description LanguageAn XML vocabularyDescribes the interfaces for web services and how to invoke the servicesService ImplementationImplementation of one or more service interfacesContains t

29、he endpoint referenceService InterfaceAbstract, reusable service definitionRepresents a type of service that can be implementedWeb Services Description LanguageServiceImplementationDefinitionServiceInterfaceDefinitionServicePortBindingPortTypeTypeMessageAB1234Web Services Description LanguageNotatio

30、nComponentUsageAService服務名稱BPort服務位置1Binding服務物件定義2Port Type服務集合定義3Message服務I/O結構定義4TypeI/O型別定義Web Services Description Language ABWeb Services Description Language 342Web Services Description Language 1Simple Object Access ProtocolDefines a standard format for XML message exchangesStylesRPC: format

31、ted payload for method invocationDocument: XML document payloadEncodingsEncodedLiteralWorks over more than just !Simple Object Access Protocol 1 POST /SMSSample/servlet/rpcrouter /1.0 2 Host: localhost 3 Content-Type: text/xml; charset=utf-8 4 Content-Length: 582 5 SOAPAction: “ 6 7 8 9 12 13 15 093

32、826624416 2330: 台積電=92.00, 13:30:0417 18 19 Service Publication and DiscoveryService PublicationMake the Service Description availableCreate the nonfunctional service descriptionTaxonomy, ownership, business name, business type, various keywords for discovery easierEndpoint details and requirementsW

33、here the description is published can vary:Directed-, diskette, Web Service Inspection Language (WSIL)UDDI Private or Universal Business RegistryService Publication and DiscoveryService DiscoveryStaticServices found and bound to at development timeFound in file system, URL, or services directoryTool

34、s browse/ search/ generate skeletons proxiesDynamicBind interface during development and Find service implementation endpoint at runtimeInterface and Endpoint found and bound at runtimeFound at URL or services directoryUDDI defines a searchable services directoryUDDIUniversal Description, Discovery, and IntegrationA project to encourage interoperability and adoption of web servicesStandards-based specifications for service description and discoveryA set of internet-based implementationsUDDI business registryInteroperating to share registrationsPartnership am