An SDN-based traffic handover control procedure and SGD management logic for EHF satellite networks

Smart Gateway Diversity (SGD) is a fundamental concept introduced to maintain high service availability in High Throughput Satellites (HTS) working at frequency bands above Ka-band. This paper proposes a novel approach for the SGD management logic that takes into account the “graceful degradation” of the link for triggering a handover of traffic among gateways (GWs.) Moreover, the paper proposes a Software Defined Network (SDN) implementation of the handover control procedure and an algorithm for building the flows matrices of the SDN switches that guarantees a fair balancing of traffic among the gateways, thus allowing a better exploitation of resources and maximization of the overall operational capacity of the HTS system. The SDN paradigm, by allowing efficient network programmability and real time re-configuration of the flow tables, enables the possibility to implement dynamic and granular resource allocation; this is a fundamental requirement for the proposed novel SGD network management approach, where re-configuration is triggered by smaller and more frequent signal-to-noise ratio (SNR) fluctuations. The performance of the proposed handover control procedures have been evaluated over real Q/V band link by using the experimental data collected through the TDP5 “Aldo Paraboni” payload embarked on the Alphasat satellite. Performance results show a gain of 40% in terms of aggregated capacity of the system with respect to the case of using an on–off SGD management logic.