A Pattern for Adaptive Behavior in Safety-Critical, Real-Time Middleware

Abstract — Patterns are a valuable method for communicating software engineering expertise about proven solutions for common problems. This paper evaluates the use of domainindependent patterns in a case study of Etherware, a middleware for networked control with a real-time, safety-critical applications model. The case study illustrates the positive and negative impact that four existing patterns have on availability, reliability, and robustness for real-time, safety-critical systems. From the results of the case study, we present the Adaptive Control Filter, a design pattern for real-time, safety-critical middleware which can mitigate timing dependencies in networked control. I