Engineering Commitment - based Business Protocols with the 2 CL Methodology ( Extended

Business protocols are a means for specifying the interaction of a set of autonomous parties with heterogeneous software designs and implementations. They have a normative value in that parties are expected to behave accordingly. Often the reality in which parties operate is characterized by a high degree of regulation. This is, for instance, the case of banking and of trading services. As new regulations are issued, there is the need of adapting business protocols to the new dictates, which usually restrict – e.g. by adding new commitments and new constraints – the possible interactions, or require the combination of different protocols. When this happens, it is important for those organizations, whose conducts are affected by the new regulation, to have the means for identifying their exposure to risks of violation. The commitment-based approach (e.g. [7, 5]) allows expressing interaction in terms of actions, whose social meaning is shared by the interacting parties. The execution of such actions affects the world and can either cause the creation of social commitments between the parties or the manipulation of already existing ones (e.g. by delegating, canceling, assigning them). Thus, commitment-based approaches naturally capture the contractual relationships among the partners rather than strictly encoding the order in which messages are to be exchanged. 2CL [2, 4] extends classical commitment-based protocols with the possibility to express temporal constraints among commitments. The article introduces 2CL Methodology, a software engineering methodology for the business protocol language 2CL, by which business protocols are specified in a declarative way by means of social commitments. Besides supporting 2CL protocol specification, 2CL Methodology includes specific guidelines for the composition and the specialization of protocols. The latter is used in the case in which a protocol must take in a new regulation or, as we say, a regulation is to be grafted upon an existing protocol [3, 1]. As an exam-