Cyber-physical systems (CPS) are devices with sensors and actuators which provide the link between the physical and the virtual world. An example is a connected vehicle able to read information from the road and combine it with cloud computing to provide new services to the driver. In many areas of CPS devices, there is a strong trend towards open systems, which can be extended during operation by instantly adding functionalities on demand. In this area, the Trusted Apps for Open Cyber-Physical Systems (TAPPS) project focuses on the functional extension provided by apps, as it is already common for mobile and other consumer devices. However, there are considerable security issues for such devices, as shown for many other IT systems like mobile devices and apps. Considering the sensitive interactions of CPS systems, including security, safety and privacy aspects, we see trust for such devices as a major societal challenge, which goes beyond the current role of computing in society.
The main goal of the TAPPS project is to extend and customize CPS devices with new 3rd party services and features in an efficient, secure and trusted apps platform. This extensibility is an important differentiator that enables new market extensions to keep pace with user expectations and latest technology. For instance, current apps for automotive vehicles provide infotainment functionality or control basic settings, both of which are not safety critical. The TAPPS solution is validated in three application domains, i.e. automotive, medical and industrial automation.
The TAPPS architecture – we are developing - provides several independent layers of security. The main characteristic security features are: (1) Computing and network virtualization based on novel, flexible hardware security mechanisms, while maintaining stringent real-time constraints in Cyber-Physical Systems (CPS) and their internal networks, (2) fine-grained access control to off-chip network resources of the smart cyber-physical device to ensure safety and privacy, and (3) formally verified applications (apps) to ensure correct and secure behavior.
For the last feature, we plan an end-to-end solution for development and deployment of trusted apps. The implementation will consist of (1) an application store for management and for deployment of CPS apps, supporting different execution environments, and (2) a model-based development toolchain for designing and implementing trusted apps including APIs and verification tools. The toolchain design will follow and extend existing standards.
