Multipath TCP (MPTCP) is the major standardised extension of the Transmission Control Protocol (TCP). MPTCP enables a regular TCP connection to use multiple networks simultaneously, increasing both application'sthroughput and reliability. Although multipath transport promises are great, they come with challenges whenthe underlying networks are heterogeneous in terms of capacity, delay and loss. In this thesis, we focus onMPTCP's performance in such heterogeneous scenarios, and how heterogeneity impacts MPTCP's operational goals.
Our main findings can be summarised as:
- We implement and evaluate a shared bottleneck detection with MPTCP's couple congestion control, which makespossible the separation of fairness aspects in MPTCP, unlocking its full potential when bottlenecks are not shared.
- We propose and implement a scheduling algorithm, which is able to improve performance, in terms of latency and throughput,in heterogeneous scenarios and reduce the amount of spurious retransmissions compared to default MPTCP.
- We propose a lightweight XOR Forward Error Correction (FEC) to aid MPTCP with subflows with heterogeneity in terms of loss,reducing loss detection and recovery time to 0-RTT.
The thesis is written within the field of Communication Systems. The work has been conducted at Simula Research Laboratory.
Prior to the defense, at 10:15, Simone Ferlin-Oliveriapresented her trial lecture "Autonomic Driving: Technical and Non-technical Challenges".
The adjudication committee
- Professor Adam Wolisz, Technische Universität Berlin,
- Professor Xiaoming Fu,Institute of Computer Science, Faculty of Mathematics and Computer Science, Georg-August-University of Goettingen,Germany
- Associate Professor Tao Yue, Department of Informatics, University of Oslo
Chair of the disputation
- Head of Department Ellen Munthe-Kaas,University of Oslo,Institute of Informatics
- Senior Research Scientist Özgü Alay,Simula Research Laboratory
- Professor Michael Welzl, Department of informatics, University of Oslo
- Professor Olav Lysne, Simula Research Laboratory