The FAA manages the largest airspace in the world with responsibility for more than 24,600,000 square miles of oceanic airspace. As such, the FAA needed to play an important role in the development and deployment of space-based ADS-B. The FAA was one of the first ANSPs to partner with Aireon to explore using space-based ADS-B and entered into an MOA in 2011. The FAA has engaged in the requirements development and the design process of the Aireon system from its inception, in order to influence critical safety and security requirements and to ensure Aireon built a robust surveillance system.