Web Services Quality ModelWeb Services Quality Model

2005. 10. 12

Dugki Min

Konkuk University

Contents

BackgroundMotivationDefinition of TermsWSQM

Quality Activity of WSQuality Associates of WSQuality Factors of WS

Related WS SpecificationsFuture Work

Background

Web Services become popular infrastructure for service-oriented integrationBusiness Web ServicesGrid Web ServicesMobile Web ServicesUbiquitous Web Services

Web Services are valuable only if whose service qualities are satisfied by the consumers and guaranteed continuously.

Motivation

Everybody uses the term, WS Quality, and says it is important. WSDM UDDI Service Contract

But, there is no clear-cut definition of what WS Quality is.

We need to have Common Model of WS Quality

=> Web Service Quality Model Common Language to describe WS Quality

=> Web Service Quality Description Language

Definition of Terms

Quality : The totality of features and characteristics of a product

or a service that bear on its ability to satisfy stated or implied needs. (ISO/IEC 9000)

Quality Model : The set of quality-related actors, activities,

characteristics of a product or a service and the relationship between them which provide the basis for specifying quality requirements and evaluating quality

WS Quality

Quality in Service-LevelIn UseIn Management

Quality

Associates

Quality

Associates

Quality Factors

(Attributes)

Quality Factors

(Attributes)

Quality

Activity

Quality

Activity

Service Stakeholder

Service Developer

Service Provider

Service Administrator (or operator)

Consumer

QoS Manager

QoS Broker (Assuror)

Service Stakeholder

Service Developer

Service Provider

Service Administrator (or operator)

Consumer

QoS Manager

QoS Broker (Assuror)

Development Quality contract

Management Quality contract

Appropriation Quality contract

Development Quality contract

Management Quality contract

Appropriation Quality contract

Quality Model

Quality Model

Business Value Quality

Service Level Measurement Quality

Interoperability Quality

Business Processing Quality

Manageability Quality

Security Quality

Business Value Quality

Service Level Measurement Quality

Interoperability Quality

Business Processing Quality

Manageability Quality

Security Quality

WSQM

Search, Negotiation, Contract, Implementation, Test, Deployment,…

Service stakeholder

ServiceDeveloper

Development Quality Contract

ServiceProvider

ServiceConsumer

Management QualityContract

ServiceServiceDevelopmentDevelopment

ServiceServiceOperation &Operation &ManagementManagement

Quality Manager

Service Broker

Service userService user

Example of Quality Activity • Development Quality Contract:

between Stakeholder and DeveloperDelivery time, Interoperability, Usability, Security

• Management Quality Contract: between Provider and Quality ManagerManageability, Composability

Service QualityContract

Quality Activity of WS

Quality Associates for WS

Consumer & Provider Stakeholder

Has a ownership of WS and requires WSQ to a developer Uses WSQM in Quality Inspection Procedure

QoS Broker Registers WS with quality properties and connect consumer and provid

er Monitors whether registered WS keep a quality level

Quality Assuror Guarantees WSQ by monitoring and controlling the quality level Focus on Legal Assurance

3rd Party Quality Manager(3PQM) Deputy manager of WS-provider Monitors and manages system to secure required quality level from out

side Focus on Technical Management

Quality Associates for WS

Quality Factors (Attributes) of WS

Related WS Specifications

SLA Contract Standards WSLA (IBM): Management by service level agreement

WS Management Standards WSMF (HP): Layered Management Framework WS-Manageability(IBM): Manageability Metamodel in type of Topic WSDM 1.0 (OASIS): OASIS standard

MUWS: Composability + ManageabilityMOWS: Manageability

Other related:WS-Addressing: to find WS resourcesWS-Notification: to notify change in resource state

Future Work

Subject to WSQM TC