Linux MP-TCP performance evaluation in a combined terrestrial-satellite access

The exploitation of Internet services leveraging multiple and different access links simultaneously is becoming a compelling use-case in current networks and upcoming 5G scenarios. In fact, recent network architectures and technologies enable multi-link access with the aim to improve both performance and service resilience/reliability. Performance improvement mainly concerns the increase of physical bandwidth through the “bonding” of multiple links, whereas reliability comes from the opportunity to implement handover and failover procedures over multiple links. At the transport layer, MP-TCP protocol was introduced as response to these needs to efficiently work on multiple links. Nonetheless, when one of the links in use is satellite (being very different in characteristics with regard to terrestrial links), it is possible to reach sub-optimal performance. The scope of the paper is to show in depth the working principles of MP-TCP before addressing, in such challenging environment, the impact of different network configurations by using a real Linux-based testbed. The results obtained can be considered as useful recommendations to future Internet Service Providers for their network configuration.