Integrating COTS Routers into Terminals for Future Protected SATCOM Systems with Dynamic Resource Allocation

Future protected SATCOM systems will be packet-switched, carrying IP traffic for voice, video, and data applications. Many of these applications will be sensitive to delay, jitter and loss. Hence, SATCOM terminals must have the ability to process, route, queue and schedule IP traffic in a manner that provides QoS differentiation and performance guarantees. In order to minimize costs and complexity, it is desirable to use COTS routers in terminals to provide the IP routing and scheduling functionality. For a COTS router to be a viable option, the router must be able to interface with the terminal modem and control software, as well as with a dynamically varying RF link layer. Due to bandwidth limitations coupled with traffic demand on the satellite uplinks and downlinks, resources are assigned dynamically to terminals as they are needed using both Time Division Multiplexing (TDM) and Frequency Division Multiplexing (FDM). In this paper, we investigate the ability of a COTS router to provide QoS functionality while restricting its egress rate to match a time-varying RF uplink channel. We then integrate the COTS router into an RF test terminal and demonstrate the interoperability of the router with the RF uplink Dynamic Resource Allocation (DRA) subsystem, the terminal modem, and control software.