Since defense budgets continue to decrease there has been a strong need to maintain or increase the effectiveness of training, while reducing costs. One way to accomplish this is to combine the strengths of live training with the advantages of distributed virtual and constructive simulation based training. The foundation for this requires good tactical radio communications between live and virtual operators. Current technologies on the market make it possible for live and virtual radios to interoperate. These products need additional cross domain solutions (CDS) and security accreditations which are often difficult to obtain. The Pacific Air Force (PACAF) and the Joint Pacific Alaska Range Complex (JPARC) use a Live Virtual and Constructive (LVC) tactical radio communications solution which only requires a single CDS solution over a distributed network such as the Combat Air Force Distributed Mission Operations (CAF DMO) Distributed Mission Operations Network (DMON).

This paper describes solutions developed for PACAF to provide radio communications interoperability between simulated radios of an AWACS simulator located at Elmendorf Air Force Base and live radios located at the JPARC in a manner which does not require additional single purpose CDS devices. To achieve this, live radio communications are required to pass through the JPARC CDS. Since live radios, the CDS, and virtual radios all have different protocol interfaces, interoperability between these three different protocols is necessary: DIS for simulated radios at the AWACS simulator, TENA for the JPARC CDS, and SIP for live JPARC radios. The need described enabled us to bridge telephony and simulation domains as well as establish a new virtual radio object model in TENA. This paper will describe interoperability considerations between SIP, TENA, and DIS protocols, differing assumptions in the telecommunications and simulation worlds which provide unique implementation challenges, and the security challenges in adding additional single purpose CDS devices to live range architectures.