Multi-Path TCP in Real-World Setups - An Evaluation in the NORNET CORE Testbed

Nowadays, cloud applications are becoming more and more popular. However, in order for such applications to work, they need a stable Internet connectivity. To avoid the Internet access becoming a single point of failure, redundancy by multi-homing - i.e. simultaneous access to multiple Internet service providers (ISP) - is becoming increasingly common as well. Multi-homing leads to the desire to utilise all network attachment points simultaneously, which is e.g. provided by the Multi-Path TCP (MPTCP) extension for TCP. MPTCP is still under development by researchers and standardisation in the IETF. Particularly, it is necessary to evaluate MPTCP under realistic Internet conditions. NORNET CORE is the world's first, large-scale Internet testbed for multi-homed systems and applications. It is therefore a useful platform for evaluating MPTCP. In this paper, we therefore present our NORNET CORE extension that adds MPTCP support to the testbed. Particularly, our extension is now available to all users of NORNET CORE as well, which significantly reduces the effort of MPTCP researchers to evaluate MPTCP and its improvements. In a proof of concept, we furthermore show the strengths and weaknesses of state-of-the-art MPTCP in NORNET CORE, in a configuration covering 29 ISP connections at 14 sites in 5 different countries.(2)