The design of state-of-the-art, complex embedded systems requires the capability of modeling and simulating the complex networked environment in which such systems operate. This implies the availability of both a networking modeling environment and traditional system-level modeling capabilities. In this paper we present a modeling and simulation methodology based on a timing accurate integration of a system-level modeling language (SystemC) and a network simulation environment (NS-2). The efficiency of the proposed design environment has been demonstrated on a description of a 802.11 MAC layer. Categories and Subject Descriptors J.6 [Computer Applications]: Computer-Aided Engineering; C.2 [Computer Systems Organization]: ComputerCommunication Networks; B.8 [Hardware]: Performance and Reliability Keywords Co-Simulation, Emulation, SystemC, Remote Debugging General Terms Algorithms, Performance