An Event-Driven Approach to Agent-Based Business Process Enactment

Abstract

Agents enacting business processes in large open environments need to adaptively accommodate exceptions and opportunities. Work on multiagent approaches can flexibly model business processes. This thesis proposes an event-driven architecture that enriches such models with events to support agile enactment of processes. Specifically, we place this architecture in a business process framework based on protocols and policies, where agents' behaviors are specified via rules. The agents interact via messages, and agreements between them are modeled by commitments. These messages and commitments provide only a high-level view of the interactions and fail to capture fine-grained details of how the interactions were carried out and whether they were carried out smoothly or not. There might be hindrances due to internal and external influences during the process, resulting in anomalies in the business process enactment. Handling such exceptions or capturing opportunities will deviate the protocol from its routine path but restore the enactment process to a stable state. We attempt to achieve this by introducing fine-grained event monitoring at specific points of the process enactment that require special attention. Detected exceptions are handled by the agent's policies. Monitoring processes and thereby recovering from errors spontaneously, results in a more reliable and proactive distributed system.

The contributions of this thesis include (1) an event-driven architecture, (2) a specification language that combines event logic with rules, (3) a methodology to incorporate events into a protocol for fine-grained monitoring, (4) an algorithm to help a designer derive high-level (complex) event patterns, (5) an algorithm to manage subscriptions to low-level events, and (6) policy-driven exception handling. This approach is applied on a well-known business scenario. A proof-of-concept prototype has been implemented to demonstrate the feasibility of the architecture. Some experiments have been carried out to demonstrate the different perspectives of commitments and different scenarios under which event monitoring proves to be useful.