Run-time service management
Barbara Pernici
Dipartimento di Elettronica e Informazione Politecnico di Milano, Italy Milano, 16 novembre 2010
Outline of course Topics • Autonomic services research issues. •Run time support of autonomic services: services retrieval, QoS negotiation and optimization, adaptive Web services
Instructor
•Barbara Pernici is professor at Politecnico di Milano since 1993 •Research interests: information systems, adaptive services, quality of services and data, green IS •Projects: –FIRB MAIS –WS-Diamond (EU) –S-Cube (EU) –GAMES (EU) –Other applied research projects
Software Services … Services •business model from products to services … •services are used, they are not owned Software services •software components that can be used … •… but are not owned Service-oriented applications •constructed by composing and configuring software services… •… most often provided by “third parties” •… software that is not under control (Traverso 2006)
Services - definitions •Service oriented architectures (SOAs) are models of distributed software components where business or scientific functions are delivered by a network of distributed services. •atomic services •composed services –A foremost approach: Web Services Execution Language for Web Services (WS-BPEL), a service composition language based on the workflow programming model.
•Components in SOAs are not only units of independent deployment, but also units of independent ownership and management by third parties.
Curbera 2007
Virtual Enterprise: Scenario
WFMS 1 Browser HTTP, IIOP,...
Customer
Any Communication
Message Queuing
Supplier Your Company
SOAP, WSDL, UDDI,...
WFMS 2
The problem
Comp 1
Comp 4
Comp 2
Comp 5
Comp 3
Comp 6
Service-oriented systems
Service Specification
Query
Publish Service Specification
Interact Requirements
Request
Response
Service
Enterprise #1 Internal code & process
Interface code exposing Well-encapsulated services Location transparent Interoperable protocols
Interface Shared process, data & service definitions
Location transparent Interoperable protocols Interface code exposing Well-encapsulated services
Internal code & process
Enterprise #2 Inter-communicating services in an SOA
Papazoglou, 2007
SOA clients & service providers Service Client (requester) Only service interfaces are exposed Service implementation is hidden from the service client Service Interface
Service Provider
Service Implementation Business Logic Data
Papazoglou, 2007
SOA collaborating services
Order Entry Req. Order Notify Buyer
Valid Order? Check Credit Hold Stock Lookup Hold Ship
Valid Order Approve
Chk Credit
FulfillOrder
Approve Notify
Papazoglou, 2007
Distribution
1 Business Domain
Order Management
Purchasing
Inventory
2 Business Processes
create, modify, suspend, cancel orders, schedule orders, create, modify, delete bulk orders, order progress
3 Business Services
4 Infrastructure Services
5 Component-based service realizations
6 CRM
Operational Systems
ERP
Databases
Packaged Applications
Legacy Applications
Layers in an SOA Papazoglou, 2007
Composition models
•Orchestration –Intra-process –Process controlled by one party
•Choreography –Inter-processes –Sequence of observable messages –Conversation among equals
Further dimensions
•When –Static composition happens at design/compile time –Dynamic composition happens while executing the process
•How –Non functional aspects like
•QoS •Security
Service life cycle
Towards managed WS
Papazoglou, CACM Oct. 2003
Towards managed WS
•Coordination –WS-BPEL –Service choreography
•QoS management
Research challenges
•Focus on: –Service management –Composed services –Adaptation –Self-management
Motivations
•Change –Requirements –Context –…
•Guarantee of service properties •Value of service and service composition •Failures
MAIS-Platform Scenario (MAIS-P)
Flexible e-services
Adaptive networks S1.op1 S1.op2 S2.op1 S2.op2
Adaptive frontends
Contextawareness and personalization
S1.op3 S2.op3
Service registry
Dynamic service selection and optimization
MAIS http://www.mais-project.it Multichannel Adaptive Information Systems – FIRB Project 2002-2006
Micro-MAIS scenario Mobile camp
Operation teams Collect field information
Sets up and coordinates teams
Traditional information system
Central site
MAIS http://www.mais-project.it Multichannel Adaptive Information Systems – FIRB Project 2002-2006
Autonomic Web Processes AWP framework
AWPs vs. Autonomic Computing
Autonomic Web Processes Business Processes
•Self Configuring: Processes configured with respect to business policies. •Self Healing: Quick responses to failures, leading to large savings in cost. •Self Optimizing: Environment changes lead to reconfiguration to a lower cost process.
Autonomic Computing Autonomic IT Infrastructure
Databases
•Self Configuring: Lower IT cost on maintenance and deployment. •Self Healing: Lower human involvement in problem detection, analysis and solving.
Networks
Servers
•Self Optimizing: Better SLAs to customers of the IT infrastructure.
Kunal Verma and Amit P. Sheth, Autonomic Web Processes, Proceedings of the Third International Conference on Service Oriented Computing, ICSOC 2005.
Architecture
Evolving Maturity and Sophistication
Human (operator) is added to the AC cycle
Autonomic interaction manager Analyze Knowledge
receive advice
Plan
Monitor
Execute
ask for help
Life cycle for adaptable service-based applications Early Requirement Engineering Requirement Engineering & Design
Identify adaptation need Identify adaptation strategy
Enact adaptation
Di Nitto, 2009
Operation & management Construction Deployment & provisioning
Š S-Cube
Service engineering vision: challenges Refine, disambiguate, detail
Context model update
Identify adaptation need Identify adaptation strategy
Early Requirement Engineering
Requirement Engineering Context model & Design
Operation & management Requirements for adaptation update
Enact adaptation
Understand engineering for adaptation
Deployment & provisioning
Requirements for adaptation
Construction Design for adaptation
Measure, control, evaluate, improve DI Nitto, Pierluigi Plebani
Š S-Cube
Traverso 2006
PAWS framework at Politecnico di Milano
D. Ardagna, M. Comuzzi, E. Mussi, P. Plebani, B. Pernici. PAWS: a framework for processes with adaptive web services. Submitted to IEEE Software.
GAMES life cycle EU Project Green Active Management of Service Centers
References •M. Papazoglou - Web services: pronciples and Technologies - Prentice Hall, 2008 •Gustavo Alonso, Fabio Casati, Harumi A. Kuno, Vijay Machiraju: Web Services - Concepts, Architectures and Applications Springer 2004 •Mike P. Papazoglou, Willem-Jan van den Heuvel: Business process development life cycle methodology. Commun. ACM 50(10): 79-85 (2007) •Mike P. Papazoglou, Paolo Traverso, Schahram Dustdar, Frank Leymann: Service-Oriented Computing: State of the Art and Research Challenges. IEEE Computer 40(11): 38-45 (2007) •P. Traverso slides 2006 •Daniel F., Pernici B., Insights into Web Service Orchestration and Choreography, IJEBR special issue on Web Services-Based E-Business Systems, Jan. 2006 • B. Pernici (ed.), Mobile Information Systems – Infrastructure and design for adaptivity and flexibility, Springer, April 2006 (The MAIS Project book) •Jana Koehler, Marco Pistore, Amit P. Sheth, Paolo Traverso, Martin Wirsing: 07061 Abstracts Collection -- Autonomous and Adaptive Web Services. Autonomous and Adaptive Web Services 2007 •Kunal Verma, Prashant Doshi, Karthik Gomadam, John A. Miller, Amit P. Sheth: Optimal Adaptation in Web Processes with Coordination Constraints. ICWS 2006: 257-264 •Bucchiarone, A.; Kazhamiakin, R.; Cappiello, C.; di Nitto, E.; Mazza, V.: A Context-driven Adaptation Process for Service-based Applications. – PESOS 2010 •D. Ardagna, M. Comuzzi, E. Mussi, P. Plebani, B. Pernici. PAWS: a framework for processes with adaptive web services. IEEE Software 2007.