Dynamic Software Updates in Cyber-Physical Systems

In Cyber-Physical Systems (CPS), computer systems are invisible, but they are embedded in real-world entities, which are monitored and controlled. A key challenge of CPS is to assure high reliability in a scalable and dynamic computing environment in the presence of frequent data propagation among CPS nodes. To effectively manage such data delivery, CPS may need a data-centric middleware, such as the Data Distribution Service (DDS) specification, which makes it easy to deal with complicated data distribution. To support higher reliability, mission-critical CPS applications are often required to provide service even during code modification. Therefore, Dynamic Software Updates (DSU) can be effectively applied for the CPS applications. This paper presents a dynamically updating approach for DDS-centric CPS applications. The proposed approach consists of the following steps: (1) to publish update requests, (2) to subscribe to the interesting update requests, (3) to discover the CPS nodes with the new version of an updated file, and (4) to perform the updates. Our initial results indicate that DSU techniques can be applied to CPS applications, which are required to support high reliability and seamless service.