This paper discusses two modeling and simulation (M&S) issues for defense cyber-physical systems (CPSs): 1) model-driven development via model interoperation and 2) simulation analysis between interoperated models. To clearly describe the network capabilities between the CPSs within network-centric warfare (NCW), we first modeled communication factors separately from the overall CPSs. The CPS models and the network model were considered discrete event systems, which were realized with DEVSim++ and ns-3, respectively. For the simulation of the two types of models, we interoperated them with high-level architecture-based middleware to preserve the independence of each one. The goal for NCW analysis is to find a balance between the computational, physical, and communication factors of the defense CPSs to achieve their missions within a networked environment. In the case study of network-centric ground warfare, the CPS models generate mission effectiveness to be analyzed according to realistic network conditions; and at the same time, the network model enables the analysis of the network performance given validated combat scenarios. We expect this paper will help simulation experts interactively analyze computational and physical capabilities of the CPSs as well as communication effects between the CPSs.