Performance evaluation of a Python implementation of the new LEDBAT congestion control algorithm

LEDBAT is a new congestion control algorithm which was proposed in an IETF draft in March 2009. LEDBAT´s goal is to provide a less-than-best-effort data transport service, i.e. a LEDBAT flow should back-off in the presence of other competing flows (TCP flows in particular). Because of its intended friendliness to competing flows, LEDBAT has already been implemented in the popular Bittorrent client uTorrent. In this paper we present performance evaluation results for our Python implementation of LEDBAT. We ran tests both in emulated networks as well as in real world networks. One of the tests involved approximately 300 volunteers spread throughout the world.