Managing Service Level Agreements in Service Oriented Product Lines Asanka Garusinghe indika perera Dulani meedeniya

Overview Service Oriented Architecture (SOA) has become advantageous architecture for productivity and flexible reusability. Software Product Line (SPL) is playing a big role of preparing core assets and making them more reusable by defining with identified commonalities and variabilities. Combining SOA and SPL increase the flexibility and reusability of the application’s components to overcome the complexity of the application. Therefore, Service Oriented Product Line (SOPL) associates with main engineering goals of both of them. Service Level Agreements (SLAs) establish the contract between service provider and service consumer for meeting the conditioning requirement related to quality attributes in web services. For managing SLAs, Web Service Level Agreement (WSLA) language specified templates have been used.

Problems How to produce actual level of Implementation for SOPL? How to analyze feature types and identify service components in SOPL environment ? How to increase the productivity of Service Providers? How to manage Quality of Services in such SOPL environment?

Related Work (Ribeiro, Heberth G. Braga, 2010) have followed some technology assessment techniques and some of development practices that can be shared with the implementations of core set of assets and managed modularity with service level of bundles (Darwish, Nagy Ramadan, Rabab Emad Mohamed, 2015) have proposed an approach to monitor quality of web services via SLAs. And also present some qualities behind web services that should be able to monitor while extracting service level objectives (SLOs) in SLA templates.

Contribution Followings: Implement SOPL environment with analyzed features and identified service components. proper managing approach for Service Level Agreements (SLAs) to monitor deviations between actual and acceptable pre-defined QoS metrics values in web service bundles via Web Service Level Agreement (WSLA) language specified templates. Road Map: Quality Management of identified bundles of services to increase the usage of service providers.

Design

Design Component 1 Component 2 Component 3 Shared WSLA template Consumer Component 2 Component 3 Shared WSLA template  

Implementation Target Development Platform : .NET & JAVA Two specific implementation : Designing and implementing service components which satisfies core assets in SOPL environmental platform. Implementing the mechanism to manage Service Level Agreements with pre- defined Quality of Service attributes in each service bundles. Key Framework: OSGI SLA Specified language : WSLA

Case Study Travel Agency : Reservation , Payment and Notifications Feature based Analysis with corresponded Feature Model

Implementation

SLA Management Open XML based SLA Template End   Start Open SLA Template XML Extract SLO s Compute and Extract Metric Values Find Variations between Predefined and Actual Values Accepted Variation End of SLO Yes No Extract SLA Variation Report Violation Open XML based SLA Template Compute Metric Values (Quality Attributes) average availability of a service minimum throughput of a service Deviation of Values Validate Accepted / None accepted Values

Evaluation Productivity Evaluate the accuracy of SLA management of SOPL environment since it reduces error and development time for service providers who takes the responsibility of making service components and their variability implementation. Scalability The service provider end, Platform can be scaled easily by producing Product Line Engineering paradigm with identified service components (core assets). Performance For the demonstration core assets management and SLA management with the running case input, the time for bundle rearrangements takes approximately 700 – 1200 milliseconds with the number of service components is 3.

Run SOPL Activate / Start Bundles of Services – Supports from OSGI Framework

Results Running WSLA Template for one of service bundles Service Level Objectives have been included in the template.

Conclusion Described an approach of implementing Service Oriented Product Lines (SOPL) which has been used as key term of handling service components that can be shared with identified commonalities and variabilities The second phase introduces management of Quality of Service (QoS) attributes of those service bundles with the defined set of terms attributes in WSLA templates, Future Work: Planed to enchance our approach with better user experience; this will support the developers who are representing service provision end and willing to manage service components accurately. Apply the implemented SOPL environment with dynamically changing SLA conditions for evaluation at real time service use.

Q&A Questions