Information superiority is one of the key challenges of a 21st century force and is achieved by digitization of the battlespace which, on the one hand, is expected to provide significant enhanced capabilities in terms of survivability, lethality, and operational tempo and, on the other hand, will require the specification and accommodation of legacy and new communications systems. Accordingly and to substantially reduce the time needed to conduct performance communications analyses for any given Joint Task Force Scenario, a modeling and simulation tool called Network Warfare Simulation (NETWARS) is being developed. This tool will provide to all the services a joint modeling and simulation shared and distributed environment over the DoD's classified internet [the Secret Internet Protocol Router NETwork (SIPRNET)], that allows it to perform communication burden analysis, contingency analysis and emerging technology analysis in the joint arena. It is based on a commercial, off-the-shelf simulation engine called OPNET and is designed to deal with large scale military networks, allow automatic integration at the simulation level of heterogeneous Information Exchange Requirement (IERs) databases, movement, environmental factors and terrain effects. The NETWARS tool is based on a modeling and simulation methodology that will guarantee interoperability and re-usability of current and future communication models.