Why NAS systems need a telecommunications overhaul

The FAA is heavily dependent upon Time Division Multiplexing (TDM)-based services provided by telecommunications carriers (e.g. AT&T, CenturyLink) to support National Airspace System (NAS) requirements. These TDM-based services are used to transport voice and data to approximately 4000 physical locations across the contiguous United States. Current trends indicate that network growth will be driven by factors such as capacity and mobility and consequently service providers are moving to unify their service offerings for multiple data sources (voice, video, and data) onto a single network with the Internet Protocol (IP) being the underlying protocol of choice. In this paper, we present the technological background of TDM and provide the rationale for the service providers' move to an all-IP network. Having looked at the trends expected in the near to mid-term future, we describe the usage patterns of TDM-based services in the FAA and identify key FAA programs that can enable the transition of up to 87% of the TDM-based services to IP. The need to migrate from TDM to IP will require the FAA to develop a strategic vision. In this paper, we present a three-point approach for such a vision that leverages the key IP-enabler programs and recommends appropriate guidance be provided to these programs to allow for a successful migration in the near- to mid-term future.