1 / 24

WSOL & WSOI - Web Service Offerings Language and Infrastructure

WSOL & WSOI - Web Service Offerings Language and Infrastructure. Vladimir Tosic, Bernard Pagurek, Kruti Patel, Babak Esfandiari , Wei Ma Network Management & Artificial Intelligence Lab Department of Systems & Computer Engineering Carleton University, Ottawa, Canada vladimir@sce.carleton.ca

freya-gaines
Download Presentation

WSOL & WSOI - Web Service Offerings Language and Infrastructure

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. WSOL & WSOI - Web Service Offerings Language and Infrastructure Vladimir Tosic, Bernard Pagurek, Kruti Patel, Babak Esfandiari, Wei Ma Network Management & Artificial Intelligence Lab Department of Systems & Computer Engineering Carleton University, Ottawa, Canada vladimir@sce.carleton.ca http://www.sce.carleton.ca/~vladimir/ WSOLpublications.html

  2. Outline • => Introduction: definition of terminology, problem statement • Web Service Offerings Language (WSOL) • Web Service Offerings Infrastructure (WSOI) • Conclusions and future work

  3. Definition of Terminology • Web Service (WS) - software application • Identified by URIs • Using XML messaging (SOAP), description (WSDL), and discovery (UDDI) • Web Service composition (orchestration, choreography, flow, network) Another WS Consumer (Requester) WS Provider (Supplier) WS

  4. Problem Statement • WSDL does not formally describe important management information • classes of service, SLAs, constraints, prices, penalties, management parties, policies, … • => Our solution: WSOL • How to implement management of WSOL-enabled Web Service and their compositions • => Our solution: WSOI

  5. => WSOL • Introduction • => Web Service Offerings Language (WSOL): • language constructs, • WSDL and WSOL, • support for management applications, • comparisons with related work • Web Service Offerings Infrastructure (WSOI) • Conclusions and future work

  6. WSOL Language Constructs • Service Offering (SO) - class of service • constraints (functional, QoS, access rights) • expressions (Boolean, arithmetic, …) • statements (prices/penalties, management responsibility) • reusability constructs (extension, constraint groups, inclusion, instantiation of constraint group templates, …) • Service Offerings Dynamic Relationships (SODRs) - can change during run-time

  7. WSDL and WSOL: Example buyStock Web Service buyStock.wsdl buyStock.wsol ServiceOffering1 accounting party: provider Constraint1: preCondition domain: buyStockOperation quantity > 0 Constraint2: QoSConstraint domain: buyStockOperation ResponseTime < 0.5 s Price: 0.5 $ ServiceOffering2 … buyStockPortType buySingleStockOperation buySingleStockRequest symbol quantity buySingleStockResponse totalStockBuyingCost … buyStockBinding buyStockPort

  8. Applications of WSOL • Web Service Management (WSM) • Measurement and calculation of QoS metrics, evaluation of constraints, accounting and billing, control of the behavior of the Web Service • WS Composition Management (WSCM) • Which WS co-operate in a composition • What contracts are used => dynamic manipulation of WSOL service offerings • Dynamic selection and negotiation of Web Services and classes of service

  9. WSOL Support for WSM • Service offerings - a lightweight alternative to SLAs, contracts, profiles • Constraints and statements - policies • QoS constraints - performance mgmt. • Price/penalty statements - accounting mg. • Functional constraints - fault management • Management responsibility statements - configuration management (part.) • Access rights - security management (part.)

  10. WSOL Support for WSCM • Service offerings dynamic relationships (SODRs) • for switching, deactivation, and reactivation of service offerings • Reusability constructs (static relationships between service offerings) • mainly for creation of service offerings

  11. WSOL - Some Related Work • Differentiated services (e.g., in telecom) • Formal specification of various constraints • Specification and management of custom-made SLAs for Web Services: • WSLA (Web Service Level Agreement) - IBM • WSML (… Management ...) - HP • SLAng - University College London • WS-Policy - IBM/Microsoft/BEA/SAP • DAML-S - the Semantic Web community

  12. Distinctive Characteristics of WSOL • Classes of service (service offerings) • Various types of constraint • Management statements • Broad set of reusability constructs • SO dynamic relationships (SODRS) • Management third parties, accounting parties • Relative simplicity • Features with lower run-time overhead • Support for WSM and WSCM

  13. => WSOI • Introduction • Web Service Offerings Language (WSOL) • => Web Service Offerings Infrastructure (WSOI): • support for monitoring of Web Services, • mechanisms for manipulation of service offerings and WSOI support for these mechanisms, • comparisons with related work • Conclusions and future work

  14. WSOI Support for WSM • WSM - monitoring of WSOL service offerings: • Measurement and calculation of QoS metrics • Evaluation of constraints • Accounting • Modules for WSM: • Based on open-source Apache Axis SOAP engine • WSOI-specific handlers and chains • Timer module • Data structures • Modules for SO Management (SOM) port types

  15. WSOI-specific Handlers and Chains: Example WSOI (Extends Axis SOAP Engine) op. call WSOIChain req. SH SOI AI RTB Pr … SOO AO QCE RTS SH … res.

  16. WSCM - Dynamic Manipulation of WSOL SOs • Switching between service offerings • Provider- or consumer-initiated • Deactivation and reactivation of SOs • With accommodation of affected consumers • Deletion of deactivated SOs • Creation of new SOs (same WSDL files) • Provider decides when it is possible and allowed • Deactivation, reactivation, deletion, and creation of SODRs

  17. Benefits of Manipulation of Service Offerings • Comparison methodology: Analytical studies and experiments with WSOI • => Simpler, faster, and incurs less overhead than re-negotiation of SLAs and switching or re-composition of Web Services • Provides additional flexibility • Enhances robustness of WS compositions • Not a complete replacement for alternatives • Can be their lightweight complement

  18. WSOI Support for WSCM • Implementation of algorithms and protocols for the manipulation of SOs • Modules for WSCM (not based on Axis): • SOMgmtDecisions module - operations with decisions about applying manipulation of SOs • Modules for SO Management (SOM) port types • Data structures (same as for WSM)

  19. SOM Port Types Monitoring of SOs: Manipulation of SOs: SessionMgmt SOM-Prov SOM-Cons SOInfo SONotification SOM-AccP SOM-MgmtP SOComparisons SOSecurity SODRMgmt

  20. WSOI - Comparison with Related Work • Related work: • Management infrastructure for WSLA • Management infrastructure for WSML • A number of WSM papers and products (often based on JMX or gateways/hubs/proxies) • Several WSCM papers and products • Management of Grid Computing • The main distinctive characteristic of WSOI: • Monitoring and dynamic manipulation of classes of service for Web Services

  21. => Conclusions and Future Work • Introduction • Web Service Offerings Language (WSOL) • Web Service Offerings Infrastructure (WSOI) • => Conclusions and future work

  22. Conclusions • WSOL and WSOI support WSM and WSCM • WSOL support for management applications: • classes of service (service offerings), • various types of constraint and statement, • relationships between classes of service, … • WSOI support for management applications: • WSOI-specific handlers and chains for Axis, • algorithms and protocols for manipulation of WSOL service offerings, • modules, data structures, SOM port types, …

  23. Current and Future Work • Full prototype implementation of the Web Service Offerings Infrastructure (WSOI) • Further experiments with the manipulation of service offerings and alternatives • Minor improvements of WSOL • Full implementation of a prototype WSOL compiler • Integration of WSOL with UDDI • …

  24. Questions, please ... • http://www.sce.carleton.ca/~vladimir/WSOLpublications.html • vladimir@sce.carleton.ca

More Related