Requirements Monitoring and Diagnosis of Software Systems

Today, large-scale and heterogeneous software systems are ubiquitous in many domains. Often, such systems are part of systems of systems (SoS) or cyber-physical systems (CPS), and work together to fulfill common goals resulting from domain or customer requirements. Such systems comprise hardware and software systems, which are commonly provided by different vendors following their own development strategies and release plans. The behavior of such systems is hardly predictable at development time and only fully emerges during operation, when the systems interact with each other and the hardware in their environment. It is thus essential to observe these complex software-intensive systems at runtime and to continuously check that they adhere to their requirements. However, approaches that have been developed for this purpose so far mainly focus on detecting violations, while subsequent support for analysis and diagnosis of violations is still rather limited. Due to the increasing size and complexity of these systems, manually diagnosing requirements violations can easily become a tedious and cumbersome task, often infeasible for people without deep knowledge of the systems and the technologies they are based on. In this project we want to address these issues by bringing together the research fields of requirements monitoring and software traceability to better relate design-time artifacts (e.g., source code or specification documents) and runtime artifacts (e.g., events and data collected from a monitored system). We expect that engineers diagnosing a violation occurring at runtime can greatly profit from traceability between the actual violation and underlying, related specification documents or source code. Our main goal is to develop a novel traceability-supported framework for diagnosing requirements violations in large-scale, heterogeneous systems. This requires (i) a thorough evaluation of the current state of the art in the area of (runtime) monitoring and traceability, and (ii) an as-is assessment of the state of the practice. Based on this assessment we aim at (iii) developing traceability-supported algorithms and an accompanying tool- supported framework for runtime diagnosis, and (iv) evaluating and iteratively improving the framework based on its application in industrial applications. The proposed research approach includes well-known research methods in the area of software engineering, such as systematic studies of the state-of-the-art in a research area, concept implementation through incrementally refined prototypes, and research evaluation through user studies and case studies.

Today, large-scale and heterogeneous software systems are ubiquitous in many domains. Often, such systems are part of Systems of Systems or Cyber-Physical Systems (CPS), and work together to fulll common goals resulting from domain or customer requirements. Typically, such systems comprise hardware and software systems, which are commonly provided by dierent vendors following their own development strategies and release plans. The behavior of such systems is hardly predictable at development time and only fully emerges during operation, when the systems interact with each other and the hardware in their environment. It is thus essential to observe these complex software-intensive systems at runtime and to continuously check that they adhere to their requirements. The main goal of the ReMonDig project was to investigate novel ways for monitoring and diagnosing errors in complex software-intensive systems. The aim was to develop tool-supported concepts and methods for combining existing, state-of-the-art runtime monitoring techniques with runtime traceability. The main research goals were related to (i) analyzing artifacts for dierent types of systems; (ii) providing support for establishing trace links between the artifacts and runtime information; (iii) providing support for maintaining artifacts during evolution; and (iv) developing tools to eciently use the provided knowledge to detect, analyze, and x violations of system requirements at runtime. We started by analyzing existing approaches in the area of runtime monitoring to uncover commonalities and variabilities between dierent application areas. As a result, we have created a descriptive framework and reference architecture for runtime monitoring approaches. The main goal of the framework is to help researchers in this area to discover and investigate already existing research and related approaches. Based on these results and initial ndings, ReMonDig has focused on two main application areas where we applied our runtime monitoring concepts and approaches. First, on providing extended diagnosis support for industrial automation systems, as part of the collaboration with Prof. Grünbacher from the Christian Doppler Laboratory MEVSS. We have successfully extended the previously developed ReMinds (http://mevss.jku.at/reminds) framework to include additional and novel diagnosis features and visualizations aiding developers and engineers to uncover and analyze errors at runtime. Second, we (together with Prof. Cleland-Huang from the University of Notre Dame) have been working on monitoring CPS, more specically, unmanned aerial vehicles (UAVS), with the development of our own Dronology (http://www.dronology.info) drone management, monitoring, and simulation framework. In both areas we were able to make signicant research contributions in the area of runtime monitoring, software and systems traceability, as well as analysis of safety-critical behavior of these systems.