Abstract
Conference Title: 2017 14th Annual IEEE International Conference on Sensing, Communication, and Networking (SECON) Conference Start Date: 2017, June 12 Conference End Date: 2017, June 14 Conference Location: San Diego, CA, USA Upload and download traffic often coexist in mobile networks. However, TCP download throughput could be substantially degraded by upload traffic even if the downlink is not the bottleneck. Previous works such as RSFC and TCP-RRE can substantially improve TCP download throughput in the presence of concurrent TCP upload flows, albeit at the expense of significantly degraded upload throughput performance. This work addresses this limitation by developing a novel Aggregate Transmission Rate Controller with Upload and Download flows aggregations (ATRC-UD) to jointly accelerate concurrent TCP upload and download flows fro/to the same mobile device. The insight is that existing TCP as well as other flow-based approaches all suffer from ACK packets delayed by data packets from TCP flows in the opposite direction, resulting in significant errors in bandwidth estimation. By contrast, ATRC-UD exploits data packets of the opposite direction to enable continuously estimation of the downlink bandwidth and queueing delay even when ACK packets are significantly delayed. This allows ATRC-UD to track the bandwidth and delay variations more closely to maintain a shorter queue length at the downlink, thus jointly improve the download-upload throughput. Extensive emulated and real-world experiments showed that ATRC-UD enables TCP to achieve 96% downlink bandwidth utilization while improving uplink bandwidth utilization by over 115% compared to existing approaches, such as TCP-RRE and RSFC.