The assessment of BitTorrent's performance using SDN in a Mesh topology

International audience– The basis of this paper is grounded upon the theoretical assumption, which states that the integration of BitTorrent with Software-defined Networks (SDNs) will degrade the performance of BitTorrent, instead of improving it. This was further evaluated by emulating this experiment on a Ring topology to verify the results. The experimental results, however, showed an unexpected behavior wherein BitTorrent outperformed under a SDN. This objective of this paper is to re-evaluate the behavior of BitTorrent in a Mesh topology instead. We have run 12 BitTorrent clients in an emulated SDN Mesh topology using Mininet and varied the virtual topology periodically by taking one link down at a time from the topology. The experimental results show when the logical topology changed periodically the performance is worse than when the topology is static for BitTorrent

Evaluating the impact of Software-Defined Networks' Reactive Routing on BitTorrent performance

International audienceSoftware-Defined Networks' technologies introduce programmatic ways to reorganize the network logical topology. To achieve this, the switches in the network interact with a set of controllers, these controllers can dynamically update the switches con- figuration based in received events. A possible practical field of use of Software-Defined Networks' is the one called Reactive Routing. On Reactive Routing the logical topology is continuously evolving based on traffic statistics as load or jitter which can be collected by the switches. BitTorrent is a well-known peer-to-peer protocol used on application layer to achieve fast propagation of content. In an effort to find the best set of connections that maximizes the global aggregation of throughput without knowledge from underlying topology, BitTorrent uses choking algorithms that continuously open and close connections to different peers. Software Defined Networks implementing Reactive Routing may be negatively affecting the performances of the system under specific conditions because of it lack of knowledge of BitTorrent strategies. Here, we review the concepts involved in Software- Defined Networks and BitTorrent protocol, we propose a classification of scenarios where these technologies may interact, we discuss hypotheses about possible problems arising from these interaction and we describe an experimental framework to study the phenomena