Linked USDL Agreement: Effectively Sharing Semantic Service Level Agreements on the Web

22nd IEEE International Conference on Web Services – ICWS 2015

Effectively Sharing Semantic Service Level Agreements on the Web

Linked USDL Agreement

José María García, Carlos Pedrinaci, Manuel Resinas, Jorge Cardoso, Pablo Fernández, Antonio Ruiz-Cortés

Outline•Introduction

•Use Case

•Linked USDL Agreement

•Evaluation and Tooling

•Conclusions and Future Work

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Introduction

•Service market is growing

•Service descriptions are available

•But…

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Challenges on SLA descriptions

•Limited support to Quality of Service (QoS) and Service Level Agreement (SLA) descriptions

•Existing SLA models problems Main focus was on technical, WS-* services No shared meaning of the content Not shareable on the Web Limited tooling support

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Requirements for our solution

•Extension to Linked USDL Linked Data based model to describe various aspects of

services

•Lightweight schema Easy to use & understand

•Promotes sharing Following Web/Linked Data principles

•Support automation for Service Level Management Available tools

•Evaluated with real use cases Cloud Computing scenario

Use case driven design

•Use case scenario on cloud computing

•Competency questions need to be answered by our model

•Taking into account existing SLA models

•Additional scenarios, such as software consultancy contracts

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Competency Questions (I)•Which functionality and quality levels does a service provide?

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Competency Questions (II)•Which service properties are guaranteed to have certain values?

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Competency Questions (III)

•Which compensation will a user obtain if the guaranteed value of some property is not provided?

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Competency Questions (IV)•Who is responsible for enforcing the guaranteed values?

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Competency Questions (V)•Who is responsible for monitoring and computing the guaranteed values?

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Competency Questions (VI)•What is the assessment period while a guarantee is provided?

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Competency Questions (VII)•How service property values are computed?

Linked-USDL Agreements model

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Agreement Terms (CQ1, CQ2, CQ3)

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Services and Entities Modeling (CQ4, CQ5)

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Agreement Conditions (CQ1, CQ2, CQ6, CQ7)

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Evaluation

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• 13 out of 22 criteria

• The rest are not shared by many approaches

• Not used in real world SLAs

• Some criteria can be covered by extensions

Tooling support

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Validity Checking

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Answering competency questions

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Answering competency questions

Conclusions and Future Work

•Extension to Linked USDL to capture SLAs

•Good coverage of SLA lifecycle

•Extensible

•Future work Improve the tooling with more operations Implementation of a service marketplace based on Linked

USDL

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Useful resources

•Linked USDL http://www.linked-usdl.org/

•Model and use cases https://github.com/linked-usdl/usdl-agreement

•Demo http://www.isa.us.es/IDEAS/Linked_USDL_Agreement/

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22nd IEEE International Conference on Web Services – ICWS 2015

Effectively Sharing Semantic Service Level Agreements on the Web

Linked USDL Agreement

José María Garcí[email protected]

@josemgarcia_us

Thank you for your attention!