Modeling and Reasoning about Service-Oriented Applications via Goals and Commitments

Abstract

Abstract. Service-oriented applications facilitate the exchange of business services among autonomous and heterogeneous participants. Traditional system modeling approaches either apply at a lower of abstraction than required for such applications or do not accommodate the autonomous and heterogeneous nature of the participants. We present a business-level conceptual model that addresses the above shortcomings. The model gives primacy to the participants in a service-oriented application. A key feature of the model is that it cleanly decouples the specification of an application's architecture from the specification of individual participants. We formalize the connection between the two-the reasoning that would help a participant decide if a specific application is suitable for his needs. We implement the reasoning in datalog and apply it to a case study involving car insurance. We also demonstrate the scalability of our approach.

Commitments and interaction norms in organisations

“…The schema of our model is standard when dealing with commitments in agents organisations: organisations consist of facts, norms, commitments and sanction, the agents can perform a set of actions which lead to the creation of commitments, and these commitments have rules in form of count-as rules and when the commitments are violated, sanctions apply [4,9,20,24,25,42,43,49,51,52,55].…”

“…Chopra et al [24] are interested in modelling exchange of services in a distributed setting. They model service-oriented application protocols in terms of messages and their effect on commitments.…”

“…For example, following a scenario in the literature [24], a car insurance agent (the Insurer) offers a customer agent (the vehicle Owner) that it will validate her car insurance if the premium is paid; it also offers a car repair garage (the Repairer) that it will approve the assessments and pay the repair costs of the cars for which the insurance have been validated; and it offers a car damage assessor (the Assessor) that it will pay for the assessment of car damages if he performs an assessment. Moreover, the assessor offers the repairer that he will assess car damages if the owner's insurance is validated.…”

“…The insurance claim scenario is described fully by Chopra et al [24] based on documentation from the Financial Services Commission of Ontario (FSCO) on the claim process. 2 It shows a situation where a number of agents interact within an organisational setting, making various offers and thereby creating commitments that in turn govern their further activities.…”

Evaluating how agent methodologies support the specification of the normative environment through the development process

“…Chopra et al [18] propose a technique to verify that an agent can potentially achieve its objectives playing a specific role, and that an agent is potentially able to honour its commitments. However, they do not provide any guideline or technique to verify the coherence of the normative system.…”