The University of Central Florida (UCF) Institute for Simulation & Training (IST) led a team investigating the impact of User Datagram Protocol (UDP) multicast for conveying information between United States Joint Forces Command (USJFCOM) Joint Live, Virtual, and Constructive (JLVC) simulation federates. This paper represents a summary of recommendations for reducing or eliminating the dependence of JLVC federates on UDP multicast. This work was funded by USJFCOM under N00189-08-D-Z020 Delivery Order 0009. Other large federations have similar configurations, so we believe our recommendations will be of general use. We decomposed the problem space into three areas: Run Time Infrastructure (RTI), simulations, and network. Our points stem from our own investigations, discussion with USJFCOM, as well as feedback from a workshop we hosted on UDP multicast issues affecting JLVC operations, attended by 38 JLVC stakeholders.
Since its inception, the number, size and complexity of these exercises have increased, lending to the increased use of UDP multicast, and causing network traffic and configuration difficulties. These difficulties will only continue to grow. Further, true resolution of these difficulties requires addressing fundamental scaling troubles. Our recommendations are divided into two scopes.
First, we provide some simple cost effective solutions to reduce short-term difficulties. These include network configuration changes to use sparse mode multicast and thorough RTI Initialization Data (RID) file optimization. Secondly, we provide longer-termed avenues that address scaling challenges more foundationally. We recommend alleviating complexities of traffic management by using software routing technologies within current RTI. More critically, we believe that long-term scalability of the JLVC Federation hinges on improving the effectiveness of Data Distribution Management (DDM) by incorporating more sophisticated mechanisms for declaration management—namely, incorporating entity dynamics. Our view is that sustainability and scalability of JLVC exercises are not addressed by the short-term options.