EFFICIENT MPTCP-BASED MULTIPATH NETWORK ACCESS FOR CONNECTED VEHICLES

Providing reliable and resilient network services to vehicles under fast mobility is a challenging aspect of designing next-generation wireless network systems. Exploiting Multipath TCP (MPTCP) to enable vehicles to use multiple wireless connections simultaneously (denoted multipath network access) is a promising solution to this challenge. However, the current design of MPTCP makes it susceptible to some major drawbacks when applied directly to improve the network performance of connected vehicles. Particularly, the fast dynamism of the characteristics (e.g., round-trip time, loss rate) of wireless connections under vehicle mobility can significantly degrade the throughput. This thesis aims to address the underlying reasons for such performance degradation and proposes a solution to overcome the challenges faced by connected vehicles. We first analyze the reasons for the throughput degrading and verify them through in-lab measurements. We then model instances where MPTCP-based multipath network access would perform worse than using the single path TCP over available wireless connections separately. Based on the analysis, we propose an efficient bandwidth aggregation scheme (EBA) that mitigates the performance drop of MPTCP under fast mobility scenarios by selectively duplicating packets over parallel access paths. This scheme has been implemented in the Linux Kernel and tested extensively through simulated scenarios. Experimental results reflect that EBA can effectively enhance the performance of MPTCP for connected vehicles