Software Defined Satellite Networks

Software Defined Satellite Network (SDSN), similar to SDN [1], decouples data plane functions from control plane functions. SDSN benefits from logically centralized network state knowledge and decision making that enables optimal resource allocations for dynamic packet processing and transmission. An SDSN network node uses forwarding tables configured by a centralized system controller to govern packet routing with embedded Layer 2 switch without requiring elaborate Layer 3 control plane software implementation in every satellite node. Besides upper layer packet queuing and switching, SDSNs also involve radio transmission links and encompass associated modulation, coding, and resource allocation functions with dynamic control. SDSN architectural concepts can be illustrated with the SPACEWAY system which uses a GEO satellite comprising Ka band spot beams and a 10 Gbps packet processing switch. The onboard switching function is orchestrated by a ground-based system controller, with centralized support for addressing, routing, and packet flow management. The SDSN building blocks and performance objectives can be extended to address inter-satellite packet routing using a constellation of satellites with inter-satellite links and enhanced routing and resource management function at the controller. Besides GEO, LEO, and MEO satellites the SDSN architecture and techniques for addressing, routing, QoS, traffic engineering, and resource management can also be utilized for aerial and high altitude networking platforms.