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Integrated Lifecycle of IT Services in a Cloud Environment. Karuna P Joshi Ebiquity Research Group, Computer Science and Electrical Engineering Dept, UMBC http://ebiquity.umbc.edu/; http://mc2.umbc.edu kjoshi1@umbc.edu. Introduction: Software Delivery Models.
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Integrated Lifecycle of IT Services in a Cloud Environment Karuna P Joshi Ebiquity Research Group, Computer Science and Electrical Engineering Dept, UMBC http://ebiquity.umbc.edu/; http://mc2.umbc.edu kjoshi1@umbc.edu
Introduction: Software Delivery Models In-house approach: Traditionally, software applications development and maintenance has been done within the company with it’s own employees. Outsourced or Off shored approach: Software applications purchased by companies. Development and maintenance is contracted to consulting/staffing companies who could be based anywhere in the world. Services on the Cloud approach: IT services purchased from software manufacturers who could be a single entity or a mix. Also termed virtualized software to imply the software development and maintenance is transparent to the consumer.
IT Services • Information Technology (IT) increasingly being viewed as a “Service” offered to an organization • Software, Customizations, Support, Hosting and Maintenance purchased as a “Service” from providers. • The X as a Service alphabet soup • Infrastructure as a Service (IaaS) • Platform as a Service (PaaS) • Database as a Service (DaaS) • Software as a Service (SaaS) etc… • Services are virtualized -- shared across multiple provisioning.
Virtualized IT Services on the Cloud • Composed of one or more components developed by one or more providers and delivered as a single service to the consumer. • Service dynamically composed • Service structure/components not pre-determined • Based on consumer’s requirements. (On demand composition) • Delivered virtually via the Cloud / grid. • Consumer specifies both functional and non functional requirements like quality, security, compliance etc.
Key Open Issues • Composition and orchestration of services currently requires a programmer with knowledge of • WSDL (Web Services Definition Language) or similar languages to describe the services. • BPEL (Business Process Execution Language) to specify the interactions between the services. • Users who are not tech-savvy cannot use this. • Currently there is no negotiation capability for service composition in cloud environment • Cannot define variable constraints or negotiate on cost, SLAs etc. • No automation of the current approach to discover services like RFPs, etc.
Our Approach • We propose a policy-based approach to automate the service lifecycle on the Cloud. • Use Semantic web languages/technologies like OWL (Web Ontology Language), RDF (Resource Description Framework) and associated reasoning infrastructure such as AIR, Jess, etc. • Extend the Service Oriented Architecture (SOA) to factor in expressive policies, negotiation and rules-based reasoning to make it more suitable for Cloud Environment.
Service Policies • Service Cost • Service Agreements • Service Obligations • Security • Compliance, Taxes etc. • Enterprise Policies • Business Processes • Budgetary rules • HR policies • Infrastructure / Facilities • Security • Compliance etc. • Service • Negotiation • Request for Service • Constraints • Provider Service Environment • Service components • Dependent Services • Service Agents • Development platform • Staging platform • Enterprise IT Service Environment • Services • Packaged applications • User devices (e.g. PCs, Laptops, PDAs etc.) • Servers • Network Infrastructure Policy for Services on the Cloud Request For service Service Level Agreement Policies Policies • Service Presentation • SaaS • DaaS • PaaS • IaaS service service CONSUMER SERVICE CLOUD PROVIDER
Methodology for Service Lifecycle • Our proposed methodology divides Service Lifecycle into Five Phases • Requirements • Discovery • Negotiation • Composition • Consumption • This Methodology is applicable on private or public cloud. • Have proposed metrics to track success of each phase. • Have developed initial version of ontologies for the five phases.
Service Requirements Service Discovery Service Negotiation Service Composition Service Consumption CONSUMER SERVICE CLOUD Phases of IT Services Lifecycle Service specified Provider(s) identified Contract signed New Service needed Service delivered
Services Requirements phase • ‘Request for Service’ Monitor • Service • Requirements • Policy Manager • Policy Type • Hard constraints • Soft constraints • Dependents • Parents policy Provider 2 Provider 1 Provider 3 Provider 4 • ‘Request for Service’ Monitor • Service • Requirements policy • Services Procurer • Service specs • Policies with constraints • RFS generator Issue Request for Service (RFS) consumer • Services Manager • Name • Provider • Type • Attributes • Location • Dependencies • ‘Request for Service’ Monitor • Service • Requirements service specs • ‘Request for Service’ Monitor • Service • Requirements Consumer Service Cloud
Service Requirements • Requirements for a service will include • Functional specifications (tasks to be automated) • Technical specifications • Software applications and constraints • Hardware Policy – Mobile device, PC, Server, Multicore etc. • Operating System Policy – single OS, multiple OS • Language Support Policy • Human Agent specifications • Agent experience • Agent skill level • Geographical location constraints • Nationality/Work permit constraints
Service Requirements (contd…) • Requirements for a service will include • Security Policy • Role • Permissions • Data Quality Policy • Low quality data may be acceptable to consumer if it provides cost saving • Service Compliance Policy • Standards adhered • Certifications needed • Government regulations adhered.
Example of Requirements Policy Data Quality policy - // allows services of low data quality to be accepted if the service is free of cost. // Using AIR Policy Language @forAll :SERVICE_QUALITY, :COST. :data_quality_policy a air:Policy; rdfs:label "Data Quality policy"; air:rule :data-quality-rule. :data-quality-rule a air:Belief-rule; rdfs:label "data quality rule"; air:pattern { :SERVICE_QUALITY quality_level :LOW. :COST service_cost :0. }; air:assert {:SERVICE_QUALITY air:compliant-with :data_quality_policy.}; air:alt { air:assert {:SERVICE_QUALITY air:NOTcompliant-with :data_quality_policy.}}.
High Level Ontology for Service Requirement Phase • Class : Request for Service • Service Domain • Exp_Svc_Begin_Date • Exp_Svc_End_Date • RFS_Respond_by_dt • Cost_constraint • Class: Human Agent Specs • Experience • Availability • Nationality • Other • Constraints • Class: • Consumer • Consumer-ID • Description • Class: • Specification • Name • Description • Class : • Functional Specs • Task • Description Class Technical Specs Must include Class: Service Compliance is part of is part of is part of is part of is sues is part of is part of Class: Data Quality policy Class: Security policy Is part of is part of is part of is part of Class: Compatible Application Details Class: Hardware Details Class: Operating System Details • Class: Domain • Domain • Characteristics Is part of Is part of
Service Discovery • Services search/discovery engine • Used to search available services that match the specifications • Identify functional gaps that exist in services discovered • Service Certification • A central registry, like UDDI, will certify a service provided. • Consumers can refer to this certification when selecting a service.
Service Verification / Certification Service Requirements Service Discovery Engine List of service providers with advertised service, service levels and cost CONSUMER SERVICE CLOUD Service Discovery phase Service Negotiation
Policy in Service Discovery phase • Policy Manager • Policy Type • Hard constraints • Soft constraints • Dependents • Parents • RFS Responder • Cost • Availability • Functionality • Requirements met • Services Procurer • Service • Policies • Generate RFS • RFS negotiation Service available policy Provider 3 Provider 4 Provider 1 Provider 2 Cannot provide service • RFS Responder • Availability policy • RFS Responder • Cost • Availability Service available consumer • Services Manager • Name • Provider • Type • Attributes • Location • Dependencies service Functionality, Requirements met • Service Provider Validation • Service • Provider • Validation • Service Composer • Components • Constraints • Functionality • Requirements met specs + Consumer Service Cloud
High Level Ontology for Service Discovery Phase • Class : Request for Service • Service Domain • Exp_Svc_Begin_Date • Exp_Svc_End_Date • RFS_Respond_by_dt • Cost_constraint • Class: Consumer • Consumer-ID • Description • Class: Service Certification • Provider • Service Name • Service ranking • Class: Provider • Service list • Description • Class : Provider List • Provider • Service details • Service availability • Service Cost used in Class: Service Search Engine Verifies Provider adds to creates returns list to
Service Negotiation • Discussion and agreement that the Service provider and consumer have regarding the Service. • Service Level Agreements (SLA) finalized between consumer and provider • Quality of Service (QoS) decided between primary provider and component providers.
Service Discovery Service Quality of Service (QoS) between primary service providers and dependent services Service Level Agreement (SLA) between consumer and primary service provider CONSUMER SERVICE CLOUD Service Negotiation phase Service Composition, Orchestration
Policy in Service Negotiation phase Iterative process • Policy Manager • Policy Type • Hard constraints • Soft constraints • Dependents • Parents • Service Negotiator • Cost • Availability • Service functionality • Requirements met • Services Procurer • Service • Policies • Generate RFS • RFS negotiation • Policy Manager • Policy Type • Hard constraints • Soft constraints • Dependents • Parents Final cost, SLA, configuration Revised soft constraints, SLA Revised soft constraints, SLA Provider 1 Provider 3 Provider 4 policy policy Revised cost, configuration Revised cost, configuration policy Iterative process consumer • Service Negotiator • Cost • Availability • Service functionality • Requirements met • Policy Manager • Policy Type • Hard constraints • Soft constraints • Dependents • Parents • Services Manager • Name • Provider • Type • Attributes • Location • Dependencies policy specs service Consumer Service Cloud Provider
High Level Ontology for Service Negotiation Phase • Class : Request for Service • Service Domain • Exp_Svc_Begin_Date • Exp_Svc_End_Date • RFS_Respond_by_dt • Cost_constraint • Class: • Consumer • Consumer-ID • Description • Class: Provider • Service list • Description • Class: • Service Level Agreement • SLA Name • Description • SLA Metrics • Penalty • Class : • Quality of Service (QOS) • QOS Name • Description • QOS Metrics • Penalty • Class : Provider List • Provider • Service details • Service availability • Service Cost Class : Service Contract is part of initiates Class: Consumer Negotiation results in used in subClass of Class: Contract Negotiation subClass of Class: Contract participates subClass of used in subClass of Class : Dependent Service Sub-Contract initiates is part of Class: Provider Negotiation results in
Service Composition Phase • One or more services provided by one or more providers are combined and delivered as a single Service. • Service orchestration determines the sequence of execution of the Service components. • Service Coupling measure determines how dependent main service is on other services or resources for its delivery • Service Cohesionmeasures the extent to which related aspects of a requirement are kept together in the same service, and unrelated aspects are kept out.
Service Negotiation Service composed Dependant services CONSUMER SERVICE CLOUD Service Composition phase Service Consumption
High Level Ontology for Service Composition Phase • Class: Provider • Service list • Description • Class: • Specification • Name • Description • Class: Service Level Agreement • SLA Name • Description • SLA Metrics • Penalty • Class : Quality of Service (QOS) • QOS Name • Description • QOS Metrics • Penalty Defines metrics for Determines Executes Class : OWL-S – Composite Process Class: Dependent Service Defines metrics for Is part of
Service Consumption Phase • Composed Service is consumed and monitored in this phase. • Key measures like Service Performance and reliability are monitored using automated tools. • Phase includes Service Delivery, Service payment. • Customer Satisfaction is tracked in this phase.
Service Composition Service consumed CONSUMER SERVICE CLOUD Service Consumption phase Service Requirements Service Monitored Service delivered – one time or periodically as needed Service payment
High Level Ontology for Service Consumption Phase • Class: • Consumer • Consumer-ID • Description • Class: Provider • Service list • Description Class : Service Contract • Class : Service Level Agreement • Task • Description refers to Part of is consumed by Provides Class : OWL-S – Composite Process Class : Tier 1 agent subClass of Class: Dependent Components Class: Human Component Class : Tier 2/ external agent Determine quality for subClass of Class : Software components Class: Presentation Class : Response Time Class : Performance Class: Assurance Class: Reliability Class : Latency Class: Security Policy Class : Throughput Class: Resolution Time
Identify functional and technical specifications Determine domain, data type and it’s acceptable quality levels “Request for Service” SERVICE CLOUD CONSUMER Service Life cycle: detailed Service Discovery Engine Service Certification List of service providers with advertised service, service levels and cost Service Level Agreement (SLA) between consumer and primary service provider Quality of Service (QoS) contracts between primary service providers and dependent services Dependant services Service composed Service Monitoring Service packaged, delivered – one time or periodically as needed Service consumed Service payment
Ongoing Work • Currently developing policies for each phase of the service lifecycle using policy languages like AIR policy language developed by MIT. • We continue to refine the IT Service ontology. Ontology in OWL for the entire Lifecycle is available at http://www.cs.umbc.edu/~kjoshi1/IT_Service_Ontology.owl • Developing an integrated quality framework for virtualized services delivered via the cloud.
Questions ? • Relevant Publications on the Ebiquity website (http://ebiquity.umbc.edu)