The emphasis here is on how reliable the network shared between Navy ships and aircraft in a strike group looks to the military user. A methodology for assessing this is outlined and then applied. As with previous RAND reports the report provides a clearly written but technically rigorous analysis. However, it is limited by the brief given.
In this case the limitation of the analysis is shown by three examples of networking in a carrier battle group. These show the IP Network, Secure Voice Equipment String and the Tactical Data Link Equipment String. These are three different networks all of which have to be supported on ships and aircraft. The logical way to make this more reliable would be to use one network which could prioritise communications and route it over all avialable links. Having separate networks devoted to two different sorts of data and voice makes little sense and is a legacy of the development of such systems.
Navy Network Dependability
Models, Metrics, and Tools
The Navy is increasingly dependent on networks and associated net-centric operations to conduct military missions, so a vital goal is to establish and maintain dependable networks for ship and multiship (e.g., strike group) networks. In this volume, the authors develop a framework for measuring network dependability that is focused on users' perceptions of whether individual network services are available, as opposed to hardware-focused measurements of whether individual pieces of equipment are functioning. The authors used this framework to modify a tool for modeling network availability that was originally developed by Space and Naval Warfare Systems Command; the modified tool allows the user to perform sensitivity analysis that captures the degree to which individual network components affect overall mission operational availability. The authors walk the reader through some exemplar analyses, then conclude with recommendations on how the Navy might facilitate future network dependability assessments, provide more meaningful results to network engineers, and, ultimately, enhance the dependability of networks across the fleet.