Algorithms and Techniques for Managing Extensibility in Cyber-Physical Systems
Pradhan, Subhav Man
Over the past decades, distributed computing paradigm has evolved from smaller and mostly homogeneous clusters to the current notion of ubiquitous computing, which consists of dynamic and heterogeneous resources in large scale. Recent advancement of edge computing devices has resulted in sophisticated and resourceful devices that are equipped with variety of sensors and actuators. These devices can be used to connect physical world with the cyber world. As such, the future of ubiquitous computing is cyber-physical in nature, and therefore, Cyber-Physical Systems (CPS) will play a crucial role in the future of ubiquitous computing. CPS are engineered systems that integrate cyber and physical components, where cyber components include computation and communication resources and physical components represent physical systems. CPS can be considered a special type of ubiquitous system that combines control theory, communications, and real-time computing with embedded applications that interact with the physical world. However, in order to realize this future of ubiquitous computing, we need to investigate and understand limitations of traditional CPS that were not meant for large-scale dynamic environment comprising resources with distributed ownership and requirement to support continuous evolution and operation. Hence, the goal is to transition from traditional CPS to the next-generation CPS that supports extensibility by allowing us to view CPS as a collection of heterogeneous subsystems with distributed ownership and capability to dynamically and continuously evolve throughout their lifetime while supporting continuous operation. This dissertation first identifies key properties and challenges for next generation, extensible CPS. The four key properties of extensible CPS are: (1) resource dynamism, (2) resource heterogeneity, (3) multi-tenancy with respect to hosted applications, and (4) possible remote deployment of resources. These properties result in various challenges. This dissertation primarily focuses on challenges arising from dynamic, multi-tenant, and remotely deployed nature of extensible CPS. In addition, this dissertation also proposes a solution to address resource heterogeneity. Overall, this dissertation presents four contributions: (1) a resilient deployment and reconfiguration infrastructure to manage remotely deployed extensible CPS, (2) a mechanism to establish secure interactions across distributed applications, (3) a holistic management solution that uses a self-reconfiguration mechanism to achieve autonomous resilience, and (4) initial approach towards a generic computation model for heterogeneous applications.