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Since the formal ratification of the European Telecommunications Standards Institute's Digital Video Broadcast-Satellite Second Generation standard in March 2005, the Department of Defense has moved to develop and integrate this technology to benefit existing Joint Programs such as GBS and the Joint IP Modem. The Defense Information System Agency has awarded a contract, under The Office of the Secretary ofDefense's Defense Acquisition Challenge Program, to demonstrate the bandwidth savings that can be achieved for the Global Broadcast Service by using the DVB-S2 waveform.Under this effort, specialized DVB-S2 transmitter and receiver equipment will be developed to include the capability to operate in the Variable Coding and Modulation mode for one-way broadcast systems. This will conclude with a live demonstration of the technology over Military Satellite and Commercial Satellite Communication assets. The demonstration will show how the DVB-S2 waveform allows for optimization ofthe broadcast to support simultaneous transmission of information to specific terminal sets with different aperture sizes, including severely disadvantaged terminals. This paper will deliver the results of this demonstration and compare it to the theoretical analysis.Concepts and techniques needed for performing Single Carrier, Multi-Code link analysis will be described. In addition this paper will discuss the advantages of the Advanced Coding and Modulation mode for two-way systems and its implementation challenges into the next generation Joint IP Modem Architecture.

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Over the last five years, the US and Coalition troop presence within the US Central Command (USCENTCOM) Area of Responsibility (AOR) has increased in support of various operations, including Operation Iraqi Freedom (OIF) and Operation Enduring Freedom (OEF). This buildup has resulted in the expansion of the satellite, ATM, fiber, and IP based networks within the CENTCOM AOR to support the Command, Control, Communications, Computers, and Intelligence (C4I) capabilities of the deployed warfighters. However, the rapid expansion of the CENTCOM network coupled with inconsistent network policies between the US Military services has resulted in the deployment of a less than optimal network architecture.In 2005, the CENTCOM J6 proposed an end-to-end engineering study to assess the state of the USCENTCOM Joint Theater C4I enterprise network. This study was meant to encompass all aspects of network operations in the CENTCOMAOR including transmission media, voice switching, data network routing, NetOps, and bandwidth management at the Defense Information Systems Network (DISN) Tier 0 and Tier ] locations. As a result, three key areas of the CENTCOM network were analyzed. satellite and ATM transmission paths, Promina multi-service access platform utilization, and IP network topology including routing and switching protocols. Technology and policy enhancements were also analyzed to see how they could be used to improve the current CENTCOM network architecture. Some ofthese enhancements include utilization of Performance Enhancing Proxies (PEP) for TCP acceleration, Digital Video Broadcast, Return Channel via Satellite (DVB-RCS) for more efficient employment of the available satellite bandwidth, and IP migration strategies. This paper follows the methodologies used in the engineering study and discusses the near and long-term optimization results that will enable dramatic improvements of the network capacity and reliability within the CENTCOM network.