When dealing with communication-intensive systems, hardware/software co-simulation usually either requires the communication to be simulated with a uniformly lour level of detail or it performs poorly. This problem manifests itself even more strongly when considering geographically distributed co-simulation, where designers take advantage of proprietary component simulation models that are made available over the Internet. In such systems, much of the communication can potentially occur over the Internet, with even, more expensive and slower communication primitives. This paper presents a technique, called "selective focus", and a Java based tool which allow communication to be represented at various levels of abstraction thus giving the designer the ability to dynamically optimize inter-module communications and improve the performance of the cosimulation.