《即时系统开发》PPT课件.ppt

薛智文http:/www.csie.ntu.edu.tw/chsueh/95 Fall,Real-Time System Development即時系統開發SOAService-Oriented Architecture,2023/7/11,/33,1,Preface,变“亚太营运中心”为“全球运筹中心 經濟現況與展望,930618,何美玥台灣經濟的願景與出路,930929,何美玥,凱達格蘭學校女性公共事務領導班Enterprise MiddlewareSOAThings should be made as simple as possible,but no simpler.-Albert Einstein Simple is not easy!,2023/7/11,/33,2,2023/7/11,/33,3,參、經濟施政之重點,2023/7/11,/33,4,一、致力創意及速度的產業政策,2023/7/11,/33,5,1.傳統產業高值化,2023/7/11,/33,6,備註：93年以後之數據為預估值。,推動成效,2023/7/11,/33,7,3.以 服務業 帶動就業並提升生活品質,目標及重點,服務業每年成長6.1。知識密集服務業每年成長8.0。,發展策略,法令鬆綁 基礎環境 發展範疇 產業政策投資誘因 釋出公有資源人才培育 激發民間活力擴張需求 創新研發機制,產業輔導,金融服務流通運輸服務通訊媒體服務醫療保健及照顧人才培訓、人力派遣及物業管理觀光及運動休閒文化創意設計服務資訊服務研發服務環保服務工程顧問服務,本部為流通運輸、觀光及運動休閒、文化創意、設計、資訊、研發等服務業的主辦機關。,2023/7/11,/33,8,3.產業電子化，台灣接單、全球生產及配送,2023/7/11,/33,9,4.產業ABCDE計畫，健全供應鏈地位,總產出：-策略性促成國際大廠擴大對台採購（每年向國內採購資訊產品超過180億美元）-擴增國內中小企業接單能力（1800餘家業者導入電子化連線作業發揮整體競爭力）-提昇國際形象與知名度（成功導入國際資訊交換標準並進而制訂國際標準深獲讚揚）-帶動國內相關產業之電子化成長（扶植國內資訊服務並傳承電子化成功經驗）,具體成效：(以神達為例）訂單達交率：95%98.4%，庫存：22億元4.3億元，訂單回覆：3.5天1.5天,IBMHPCompaq3家,國際採購商,國內系統廠商,國內零組件供應商,A計畫,B計畫,自動詢報價訂購交貨驗收付款品質管理供應商關係管理,自動詢報價訂購交貨驗收付款,IBM 體系：20家Compaq 體系：10家HP 體系：12家合 計：42家次,宏碁體系：240家神達體系：212家華碩體系：979家：合 計：3955家次,威盛鴻海光寶國碁國巨世平.等1,800家,宏碁神達華碩大同英業達.等15家,2023/7/11,/33,10,產業需求/規格分析問題追蹤管理設計資料共享管理,全球收付款、融資全球資金調度管理,宏碁、神達、華碩、大同,客戶及策略合作夥伴,C計畫,E計畫,D計畫,貨況追蹤庫存管理全球運輸規劃通關文件管理,物流,資訊電子製造體系,威盛台積電日月光建準瑞軒.,Delivery,物流服務業,CDE計畫成效：融資金額：92年底達120億，93年第1季達230億，93年底預估可達600億物流資訊透通：導入12個主要國家之出到貨及組裝據點，連結國內外物流平台及主要客戶Hub計16個。導入六個體系計有19家國際客戶及164家供應商一起參與建構各具特色的研發價值網路之虛擬社群。,鼎新、仲訊、偉盟、關貿、汎宇、太一信通、怡康、訊豐.,鴻霖、中菲行、寶靈頓、長榮、陽明.,2023/7/11,/33,11,伍、願景高值台灣、運籌全球,2023/7/11,/33,12,Focus on Enterprise Middleware,Why?Who?What?When?Where?How?,2023/7/11,/33,13,Introduction to SOA,Service-Oriented Architecturea Standard fOr Architecture description Society Of ActuarySociety Of Ancients,2023/7/11,/33,14,What is an Architecture?,The architecture of an IT system is the structure or structures of the system,which comprise software and hardware components,the externally visible properties of those components,and the relationships among them.(Adapted from Bass et al.1),2023/7/11,/33,15,What is a Service-Oriented Architecture(SOA)?,SOA is an architectural style whose goal is to achieve loose coupling among interacting software agents.A service is a unit of work done by a service provider to achieve desired end results for a service consumer.Both provider and consumer are roles played by software agents on behalf of their owners.,2023/7/11,/33,16,Service-Oriented Architecture(1),An accepted industry model for representing applications on the network as reusable services.Various interface standards exist for these services.range from DCE/RPC and CORBA,DCE source code is now available under an Open Source license(LGPL).through stored procedures to Web Services.An architectural style whose goal is to achieve loose coupling among interacting software agents.,2023/7/11,/33,17,Service-Oriented Architecture(2),In all cases,requests are made of the services by a calling application that expects some form of reply;often referred to as request/reply.A fundamental element of Service-Oriented Architectures is the separation of interface from implementation.This enables a more loose coupling between the service consumer and the service provider.The separation is enabled by means of a metadata layer that makes the interface definition available at design time.,2023/7/11,/33,18,How does SOA achieve loose coupling?,Employing two architectural constraints:A small set of simple and ubiquitous interfaces to all participating software agents.Only generic semantics are encoded at the interfaces.The interfaces should be universally available for all providers and consumers.Descriptive messages constrained by an extensible schema delivered through the interfaces.No,or only minimal,system behavior is prescribed by messages.A schema limits the vocabulary and structure of messages.An extensible schema allows new versions of services to be introduced without breaking existing services.,2023/7/11,/33,19,Additional Constraints,There are a number of additional constraints one can apply on SOA in order to improve its scalability,performance and,reliability.Stateless Service Stateful Service Idempotent Request,2023/7/11,/33,20,Deriving Web Services from SOA,A web service is a SOA with at least the following additional constraints:Interfaces must be based on Internet protocols such as HTTP,FTP,and SMTP.Except for binary data attachment,messages must be in XMLThere are two main styles of Web services:SOAP web services and REST web services.,2023/7/11,/33,21,SOAP Web services,Except for binary data attachment,messages must be carried by SOAP.The description of a service must be in WSDL.A SOAP RPC web service breaks the second constraint required by an SOA.,2023/7/11,/33,22,REST Web Services,Interfaces are limited to HTTP.The following semantics are defined:HTTP GET is used for obtaining a representation of a resource.A consumer uses it to retrieve a representation from a URI.Services provided through this interface must not incur any obligation from consumers.HTTP DELETE is used for removing representations of a resource.HTTP POST is used for updating or creating the representations of a resource.HTTP PUT is used for creating representations of a resource.Most messages are in XML,confined by a schema written in a schema language such as XML Schema from W3C or RELAX NG.Simple messages can be encoded with URL encoding.Service and service providers must be resources while a consumer can be a resource.,2023/7/11,/33,23,An SOAnot just Web services,Within a business environment,a pure architectural definition of an SOA might be an application architecture within which all functions are defined as independent services with well-defined invokable interfaces,which can be called in defined sequences to form business processes.two critical characteristics to be realized:the services are truly independent,they can be managed.,2023/7/11,/33,24,Management includes,Securityto authorize requests,encrypt and decrypt data as required,and validate information.Deploymentto allow the service to be moved around the network to maximize performance or eliminate redundancy to provide optimum availability.Loggingto provide auditing and metering capabilities.Dynamic reroutingto provide fail-over or load-balancing capabilities.Maintenanceto manage new versions of the service.,2023/7/11,/33,25,What is a service?,a simple business capabilitygetStockQuote,getCustomerAddress or checkCreditRatinga more complex business transactioncommitInventory,sellCoveredOption or scheduleDeliverya system service logMessageIn,authenticateUser,2023/7/11,/33,26,Why migrating to a service-oriented architecture?,ProblemsComplexityEnterprise Application Integration(EAI)tops the priority list of many CIOsredundant and nonreusable programmingas a result of mergers and acquisitionsmultiple interfacesthe n(n-1)integration problem,2023/7/11,/33,27,What about the future?,Java technology has provided platform-neutral programming.XML has provided self-describing,platform-neutral data.Web services have removed another barrier by allowing applications to interconnect in an object-model-neutral way.For example,using a simple XML-based messaging scheme,Java applications can invoke Microsoft.NET applications or CORBA-compliant,or even COBOL,applications.,2023/7/11,/33,28,Common Misconceptions about SOA,Web services are just like distributed objects Web services is RPC for the Internet Web Services need HTTP Web services need web serversWeb services are reliable because they use TCP Web services debugging is impossible,2023/7/11,/33,29,Distributed Computing Environment(DCE),LGPL?,2023/7/11,/33,30,Enterprise Workframe Architecture,2023/7/11,/33,31,Where to Open?,Back-end,Front-end,J2EE.NETCORBADCOMDCEWebsphereBiztalk,:interfaces to open,Company A:Service 1,2023/7/11,/33,32,Enterprise Middleware Platform,關務,後勤,物流,金流,Open 物流 Middleware Interface,J2EE,CORBA,.NET,open,open,middlewares,Open Interface Platform,open,2023/7/11,/33,33,Reference,”全球运筹中心计划”http:/w2kdmz1.moea.gov.tw/chief/up/930618經濟現況與展望.ppt經濟現況與展望.ppthttp:/w2kdmz1.moea.gov.tw/chief/up/930929台灣經濟的願景與出路.ppt台灣經濟的願景與出路.pptWhat is Architecture?What is Service-Oriented Architecture?Migrating to a service-oriented architectureWeb Services are not Distributed Objects:Common Misconceptions about Service Oriented Architectures What is Distributed Computing and DCE?,