Authors | N. Khademi, M. Welzl, G. Armitage, C. Kulatunga, D. Ros, G. Fairhurst, S. Gjessing, and S. Zander |
Title | Alternative Backoff: Achieving Low Latency and High Throughput with ECN and AQM |
Afilliation | Communication Systems, Communication Systems, Communication Systems |
Project(s) | The Center for Resilient Networks and Applications |
Status | Published |
Publication Type | Technical reports |
Year of Publication | 2015 |
Date Published | 07/2015 |
Publisher | Centre for Advanced Internet Architectures (CAIA), Swinburne University of Technology |
Place Published | Melbourne, Australia |
Abstract | CoDel and PIE are recently proposed Active Queue Management (AQM) mechanisms that minimize the time packets spend enqueued at a bottleneck, instantiating shallow, 5 ms to 20 ms buffers with short-term packet burst tolerance. However, shallow buffering causes noticeable TCP performance degradation when a path’s underlying round trip time (RTT) heads above 60ms to 80ms (not uncommon with cross-continental and inter-continental traffic). Using less-aggressive multiplicative backoffs is known to compensate for shallow bottleneck buffering. We propose ABE: “Alternative Backoff with ECN”, which consists of enabling Explicit Congestion Notification (ECN) and letting individual TCP senders use a larger multiplica- tive decrease factor in reaction to ECN-marks from AQM- enabled bottlenecks. Using a mix of experiments, theory and simulations with standard NewReno and CUBIC flows, we show significant performance gains in lightly- multiplexed scenarios, without losing the delay-reduction benefits of deploying CoDel or PIE. ABE is a sender- side-only modification that can be deployed incrementally (requiring no flag-day) and offers a compelling reason to deploy and enable ECN across the Internet. |
URL | http://caia.swin.edu.au/reports/150710A/CAIA-TR-150710A.pdf |
Citation Key | abe-caia-2015 |