A Technique and a Tool to Detect Emergent Behavior of Distributed Systems Using Scenario-Based Specifications

Distributed systems are employed in countless applications such as information systems, robotics, etc. Lack of central control makes the design of such systems a challenging task because of possible unwanted behavior at runtime, commonly known as emergent behavior. Developing a methodology to detect emergent behavior in the pre-implementation stages of the software development life-cycle of distributed systems can potentially lead to huge savings in time and cost. Moreover, due to the typical large size of the modern distributed systems, automating the detection methodology is considered greatly beneficial. An effective and efficient approach for the design of distributed systems is to describe system requirements using scenarios. A scenario, commonly known as a message sequence chart (MSC), is a temporal sequence of messages sent between system components. However, scenario-based specifications may contain subtle deficiencies with respect to analysis and validation known as incompleteness and partial description. In this research, a tool to automatically detect emergent behavior of scenario-based specification of distributed systems is developed and demonstrated using a robotics example.