1、 2002 IBM Corporation面向服务的体系架构面向服务的体系架构(SOA)(SOA)日程日程1.1.什么是面向服务的体系架构什么是面向服务的体系架构2.2.SOASOA的价值的价值3.3.构成构成SOASOA的技术的技术4.4.如何构建如何构建SOASOA系统系统5.5.IBMIBM的的SOASOA工具与产品工具与产品6.6.网格计算与网格计算与SOASOA2 一个组件模型 将应用程序的不同功能单元（服务）通过这些服务之间定义良好的接口和契约联系起来。接口是采用中立的方式进行定义的，它应该独立于实现服务的硬件平台、操作系统和编程语言。构建在各种这样的系统中的服务可以以一种统一和通
2、用的方式进行交互。什么是什么是面向服务的体系架构?3为什么采用面向服务的体系架构为什么采用面向服务的体系架构?A Service Oriented Architecture enables flexible connectivity of applications or resources by Representing every application or resource as a service with a standardized interfaceEnabling them to exchange structured information(messages,document
3、s,business objects)Mediating the message exchange through an Enterprise Service Bus This flexibility enables new and existing applications to be easily and quickly combined to address changing business needs.The ability to easily combine/choreograph applications allows IT services to more readily re
4、flect business processes The SOA infrastructure is also used to facilitate the management of business performance and quality of service4Flexible Business ModelsTransformationBusiness Process OutsourcingMergers,Acquisitions&DivestituresFlexible IT ArchitectureRequiresComposableServicesSoftware Devel
5、opment IntegrationInfrastructureManagementComposableProcessesService Oriented Architecture(SOA)DevelopmentInfrastructureManagementSOASOA的价值的价值:SOA:SOA实现可变的实现可变的ITIT架构架构 5构成构成SOASOA的技术的技术 什么是服务什么是服务 服务调用服务调用 服务的编排服务的编排 服务的发现服务的发现6什么是服务什么是服务?A well-defined,invokable unit of business function Accesses
6、business data or facilitates a change of business datafrom one valid and consistent state to another.Defined using explicit interfacesIndependent of service implementationsProvides contract between service requestors and service providers Invokable through common communication protocolsProvides inte
7、roperability and location transparency.7服务描述服务描述 Services are described using a standardized interface(metadata)Defines the service,its operations,and input and output parametersDefines how the service is reached and its location Input and outputs may be simple parameters or XML documents An existin
8、g application can be given a service faadeThe faade(e.g.an EJB)is then described as the service Web Services Description Language(WSDL)is the standard used to describe the service8服务描述服务描述:WSDL:WSDL WSDL(Web Services Description Language)is an XML document that describes a Service using a number of
9、key elements:A Port Type defines what the service does,and is described by a number of operations.For each operation the data that it receives and sends is described by a MessageThe Binding defines how the service(as described by the Port Type)is invoked e.g.SOAP/HTTP,SOAP/JMS.The Port specifies the
10、 address where the service is located9服务调用服务调用 Services interact by exchanging data over an Enterprise Service Bus The Enterprise Service Bus is a logical architectural constructProvides inter-connectivity servicesServices interact with each other based on the quality of service requirements of the
11、individual transactions ESB connects and integrates an enterprises IT businessIn different locations,using different transports,across organizations ESB mediates service requests and responsesPerforms transformation and routingEnables connection type transparency ESB enables the use of multiple prot
12、ocolse.g.SOAP/HTTP can be converted to SOAP/JMS and vice versa10企业服务总线企业服务总线(ESB)Central to the Workings of a Service Oriented ArchitectureTransport ServicesSynchronous/AsynchronousPersistent/Non-persistentLoosely-coupled/Tightly-coupledEvent ServicesPublish and Subscribe Mediation ServicesRouting T
13、ransformationStandards BasedHTTP/HTTPS with option for WS-ReliableMessagingJMS,JAX-RPC,SOAPWS-Security,WS-Policy,WS-Addressing11服务的编排术服务的编排术 Business processes are a set of activities carried out in a sequence Services can be choreographed to implement a business processi.e.each step or activity in
14、a business process is implemented by a service The business process itself becomes a service Service choreography is described by the Business Process Execution Language(BPEL)A standard proposed to OASIS for process definition Service Choreography provides:Processes that combine applications and peo
15、pleTransactionality and compensationManipulation of process data12服务的发现服务的发现 A Service Registry or DirectoryPublishes service descriptionsFinds business,services and service interfacesUDDI is a standard for a registry web service(see UDDI.org)Service discovery may be at design time or run timeWebSph
16、ere Studio provides Web Services Explorer to publish and search UDDIUDDI Service entries contain URL of its WSDL A UDDI directory may be private to an enterprise WSDL for services may be stored in local files and directories ESB mediations may be used to determine services location at run timeServic
17、eRegistry13SOA 的服务栈的服务栈SOA uses Web Services specifications to implement its featuresMany Web Services specifications are being standardizedIBM and other vendors have implemented these specifications,anticipating the standardsThe Web Service function stack is rich and getting richer14如何构建如何构建SOASOA的
18、系统的系统 Develop a service oriented mentalityEverything is a service Understand and define servicesGood service decomposition is the challengeRemember coarse granularitySome service implementations will exist,others will need to be created Determine service interfaces and interaction patternsWhat forma
19、ts will be adopted for data exchange?What qualities of service will bound interactions?Where will mediation be required/appropriate?Define service orchestrations in terms of supported business processes Composite services will generally reflect business processes?What are the business processes?Busi
20、ness models in WebSphere BI Modeler can prove invaluable here 15采用采用 SOA SOA 的四个层次的四个层次 16实现单独的实现单独的 Web Web 服务服务17面向服务的集成面向服务的集成18企业范围内的企业范围内的 IT IT 转换转换 19Enterprise applicationsEnterprise dataData Access ServicesApplication Access ServicesIBM Software Offerings Monitoring ServicesIBMIBM商务整合的参考架构商
21、务整合的参考架构Model,design,development,test toolsCommon Runtime InfrastructureWebSphere BI ModelerWebSphere BI MonitorWeb Services GatewayWebSphere BI Event/Message BrokerWebSphere MQWebSphere BI AdaptersDB2 Information Integrator ClassicWebSphere StudioDB2 Information IntegratorWebSphere Business Integra
22、tion Server WebSphere Business Integration Connect WebSphere Application ServerEnterprise Service BusProcessServicesCommunity Integration ServicesApplication ServicesInformation Services WebSphere Portal ServerUser Interaction Services20Professional ServicesNetworkOGSA EnabledStorageOGSA EnabledServ
23、ersOGSA EnabledMessagingOGSA EnabledDirectoryOGSA EnabledFile SystemsOGSA EnabledDatabaseOGSA EnabledWorkflowOGSA EnabledSecurityOGSA EnabledWeb ServicesOGSI Open Grid Services InfrastructureGrid ServicesSystem Management SevicesOpen Grid Services Architecture(OGSA)ApplicationsAutonomic Capabilities
24、OGSAOGSAOGSA Structure 21GridGrid和和WebWeb服务服务GridWebThe definition of WSRF means that Grid and Web communities can move forward on a common base WSRFStarted far apart in apps&techOGSIGT2GT1HTTPWSDL,WS-*WSDL 2,WSDMHave beenconverging 22网格计算与网格计算与SOASOA 网格系统本身就是网格系统本身就是SOA 在网格服务上构建应用程序级在网格服务上构建应用程序级 S
25、OA23ESBESB实现服务网格实现服务网格:例证例证MQMessageBrokersApplicationServersIntegrationServerMQPortalWeb ClientsWeb BrowsersLegacyApplications The ESB within the enterprise will evolve based on QOS requirements required by service interactions This will be augmented by mediations running in Message Broker and/or the Web Services Gateway.24总结总结 Service Oriented Architecture provides the flexibility required to operate in an On-Demand Environment 2526272829
