This project develops an integrated framework of communications, computation and control for understanding wide-area power system performance in the face of unpredictable disturbances. The power system is chosen as a particularly challenging cyber physical system (CPS) due to its extreme dimension, geographic reach and high reliability requirements. The following tasks are studied in the proposed research: (a) a Partial Difference Equation (PdE) framework to model the impact of network topology on the power system stability; (b) the design of a communication network for CPS, based on the PdE modeling;(c) the design of a control system, which addresses the challenges such as fast response and resource constraints; (d) the design of a computing infrastructure, which addresses the computation for controlling the power network, in particular, the communication complexity for controlling the power network in both cases of one-snapshot computation and iterative computations; and (e) the test and evaluation for both small scale system models of several hundred buses and very large system models of ~50,000 buses. This work contributes to the broader understanding of CPS with high reliability requirements, particularly, critical infrastructures such as the power grid. Modern infrastructures are complex systems of communications and computation tied to the controls of the physical system. The proposed research contributes to improved reliability by addressing the propagation of disturbances and advancing the understanding of geographically distributed CPS. The PIs plan to open multiple courses on CPS related to the proposed research.