معماری سرویس گرا (۲)

معماری سرویس گرا (۲)

اسلاید 1: 1What is a Service Oriented Architecture?Prof. Paul A. StrassmannGeorge Mason University, November 19, 2007

اسلاید 2: 2Problems Addressed by a Service Oriented Architecture

اسلاید 3: 3Purpose of Architecture: To Manage Interdependencies

اسلاید 4: 4Directions of System Architecture1960 - 19801990 - 2000Organization FocusMainframe CentricInternal UseUnique DataProcess FocusClient ServerPartial ConnectivityEDI File Transfer2010 - 2050Distributed FunctionsData CentricUniversal InteroperabilityReal-time Connectivity

اسلاید 5: 5Data Interoperability Expands as Response Time Shrinks

اسلاید 6: 6Interoperability Does not Scale

اسلاید 7: 7What is a Service Oriented Architecture (SOA)?A method of design, deployment, and management of both applications and the software infrastructure where: All software is organized into business services that are network accessible and executable. Service interfaces are based on public standards for interoperability.

اسلاید 8: 8Key Characteristics of SOAQuality of service, security and performance are specified. Software infrastructure is responsible for managing. Services are cataloged and discoverable. Data are cataloged and discoverable. Protocols use only industry standards.

اسلاید 9: 9What is a “Service”?A Service is a reusable component.A Service changes business data from one state to another.A Service is the only way how data is accessed.If you can describe a component in WSDL, it is a Service.

اسلاید 10: 10Information Technology is Not SOABusiness MissionInformation ManagementInformation Systems Systems Design Computing & CommunicationsInformation TechnologySOA

اسلاید 11: 11Current Infrastructure Costs are Excessive ($ Millions, I.T. Costs)SOA

اسلاید 12: 12Contractors Will Build Separate Infrastructures without SOA

اسلاید 13: 13Why Getting SOA Will be Difficult Managing for Projects:Software: 1 - 4 yearsHardware: 3 - 5 years;Communications: 1 - 3 years;Project Managers: 2 - 4 years;Reliable funding: 1 - 4 years;User turnover: 30%/year;Security risks: 1 minute or less.Managing for SOA:Data: forever.Infrastructure: 10+ years.

اسلاید 14: 14Why Managing Business Systems is Difficult?40 Million lines of code in Windows XP is unknowable.Testing application (3 Million lines) requires >1015 tests.Probability correct data entry for a supply item is <65%.There are >100 formats that identify a person in DoD.Output / Office Worker: >30 e-messages /day.

اسلاید 15: 15How to View Organizing for SOA STABILITY HEREVARIETY HERECorporate Policy, Corporate Standards, Reference Models, Data Management and Tools, Integrated Systems Configuration Data Base, Shared Computing and TelecommunicationsApplications Development & MaintenanceENTERPRISE LEVELPROCESS LEVELBUSINESS LEVELAPPLICATION LEVELLOCAL LEVELGraphic InfoWindow, Personal Tools, Inquiry LanguagesCustomized Applications, Prototyping Tools, Local Applications and Files ApplicationsSecurity BarrierBusinessSecurity BarrierProcessSecurity BarrierPrivacy and Individual Security BarrierGLOBAL LEVELIndustry Standards, Commercial Off-the-Shelf Products and ServicesPERSONAL LEVEL Private Applications and Files Functional Process AFunctional Process BFunctional Process CFunctional Process DOSDService AService B

اسلاید 16: 16SOA Must Reflect Timing Corporate Policy, Corporate Standards, Reference Models, Data Management and Tools, Integrated Systems Configuration Data Base, Shared Computing and Telecommunications, Security and SurvivabilityBusiness ABusiness BInfrastructureSupportApplications Development & MaintenanceENTERPRISEPROCESSBUSINESSAPPLICATION LOCALGraphic InfoWindow, Personal Tools, Inquiry LanguagesCustomized Applications, Prototyping Tools, Local Applications and Files GLOBALIndustry Standards, Commercial Off-the-Shelf Products and ServicesPERSONAL Private Applications and Files Functional Process AFunctional Process BFunctional Process CFunctional Process DLONG TERM STABILITY &TECHNOLOGYCOMPLEXITYSHORT TERM ADAPTABILITY &TECHNOLOGYSIMPLICITY

اسلاید 17: 17SOA Must Reflect Conflicting InterestsEnterpriseMissions OrganizationsLocalPersonal

اسلاید 18: 18DoD Concept How to Organize for SOAEnterprise Information EnvironmentBusiness Mission WarFighting MissionIntelligence MissionArmy, NavyAir ForceAgencies CombatantCommandsProgramsFocus of this Presentation

اسلاید 19: 19Organization of Infrastructure Services InfrastructureServices(Enterprise Information)DataServices SecurityServicesComputingServices Communication ServicesApplicationServices

اسلاید 20: 20Organization of Data Services DataServices DiscoveryServices ManagementServices CollaborationServices InteroperabilityServices SemanticServices

اسلاید 21: 21Data Interoperability Policies Data are an enterprise resource.Single-point entry of unique data.Enterprise certification of all data definitions.Data stewardship defines data custodians. Zero defects at point of entry.De-conflict data at source, not at higher levels.Data aggregations from sources data, not from reports.

اسلاید 22: 22Example of Data Pollution

اسلاید 23: 23What Data?

اسلاید 24: 24Data ConceptsData Element Definition Text associated with a unique data element within a data dictionary that describes the data element, give it a specific meaning and differentiates it from other data elements. Definition is precise, concise, non-circular, and unambiguous. (ISO/IEC 11179 Metadata Registry specification) Data Element Registry A label kept by a registration authority that describes a unique meaning and representation of data elements, including registration identifiers, definitions, names, value domains, syntax, ontology and metadata attributes. (ISO 11179-1).

اسلاید 25: 25Data and Services Deployment PrinciplesData, services and applications belong to the Enterprise. Information is a strategic asset. Data and applications cannot be coupled to each other. Interfaces must be independent of implementation. Data must be visible outside of the applications.Semantics and syntax is defined by a community of interest. Data must be understandable and trusted.

اسلاید 26: 26Organization of Security Services SecurityServices TransferServices ProtectionServices CertificationServices SystemsAssuranceAuthenticationServices

اسلاید 27: 27Security Services = Information AssuranceConduct Attack/Event ResponseEnsure timely detection and appropriate response to attacks. Manage measures required to minimize the network’s vulnerability.Secure Information ExchangesSecure information exchanges that occur on the network with a level of protection that is matched to the risk of compromise. Provide Authorization and Non-Repudiation ServicesIdentify and confirm a users authorization to access the network.

اسلاید 28: 28Organization of Computing Services ComputingServices ComputingFacilitiesResourcePlanning Control &Quality ConfigurationServices FinancialManagement

اسلاید 29: 29Computing Services Provide Adaptable Hosting EnvironmentsGlobal facilities for hosting to the “edge”. Virtual environments for data centers. •Distributed Computing InfrastructureData storage, and shared spaces for information sharing.•Shared Computing Infrastructure ResourcesAccess shared resources regardless of access device.

اسلاید 30: 30Organization of Communication Services CommunicationServices Interoperability ServicesSpectrumManagement ConnectivityArrangements Continuity ofServices Resource Management

اسلاید 31: 31Network Services ImplementationFrom point-to-point communications (push communications) to network-centric processes (pull communications).Data posted to shared space for retrieval.Network controls assure data synchronization and access security.

اسلاید 32: 32Network Control is the Key

اسلاید 33: 33Communication ServicesProvide Information TransportTransport information, data and services anywhere.Ensures transport between end-user devices and servers. Expand the infrastructure for on-demand capacity.

اسلاید 34: 34Organization of Application Services Application Services Component Repository Code BindingServicesMaintenanceManagementPortalsExperimentalServices

اسلاید 35: 35Application Services and Tools•Provide Common End User Interface ToolsApplication generators, test suites, error identification, application components and standard utilities.Common end-user Interface Tools.E-mail, collaboration tools, information dashboards, Intranet portals, etc.

اسلاید 36: 36Example of Development Tools Business Process Execution Language, BPEL, is an executable modeling language. Through XML it enables code generation.Traditional Approach BPEL Approach- Hard-coded decision logic - Externalized decision logic- Developed by IT - Modeled by business analysts- Maintained by IT - Maintained by policy managers- Managed by IT - Managed by IT- Dependent upon custom logs - Automatic logs and process capture- Hard to modify and reuse - Easy to modify and reuse

اسلاید 37: 37A Few Key SOA Protocols Universal Description, Discovery, and Integration, UDDI. Defines the publication and discovery of web service implementations. The Web Services Description Language, WSDL, is an XML-based language that defines Web Services. SOAP is the Service Oriented Architecture Protocol. It is a key SOA in which a network node (the client) sends a request to another node (the server).The Lightweight Directory Access Protocol, or LDAP is protocol for querying and modifying directory services.Extract, Transform, and Load, ETL, is a process of moving data from a legacy system and loading it into a SOA application.

اسلاید 38: 38SOA Interoperability Goals for the Department of DefenseInteroperability of solutions across the DoD strategic goal. Rules for sharing of data and services across the enterprise. Enforcement of standards.All data, services, and applications shall be accessible, understandable, and trusted.Global Information Grid for sharing of information with Federal Departments, Department of Homeland Security, the Intelligence Community, state and local governments, allied, coalition, non-governmental organizations (NGOs), academic, research and business partners.

اسلاید 39: 39Example of Customizable Web Services (www.salesforce.com)

اسلاید 40: 40Why SOA Saves Code Provides a standard way of interacting with shared software.Enables software to become building blocks for reuse.Shifts focus to application assembly rather than design.Creates new applications out of existing components.Integrates with applications in other enterprises.

اسلاید 41: 41Preservation of Assets is the Purpose of SOAWhat the Customer Trains to Apply;ApplicationsUsageOpen Systems,Equipment,Software,CommunicationsData &Systems Integration;CommunicationsInfrastructureArchitectureShort-termAsset(An Enterprise Function)>70% of CostObsolescentCommodity Asset(Outsource According toArchitecture)<20% of CostLong - termAsset(An Enterprise Function)<10% of Cost

اسلاید 42: 42Impacts of Information Technologies Information drives economic “arms race”. Obsolete assets will be discarded. Collaboration favors global consolidation. I.T. becomes an economic weapon.

اسلاید 43: 43A Historical Perspective