Research Areas

TCP latency measurement and solution

Emerging applications like VR, AR, and 360-degree video aim to exploit the unprecedentedly low latencies. In order to fulfill them, it is crucial to understand where packet delays happen. In this work, we empirically find that sender-side protocol stack delays can cause high end-to-end latencies. Unfortunately, however, current latency diagnosis tools cannot even distinguish between delays on network links and delays in the end hosts. We present ELEMENT, a latency diagnosis framework that decomposes end-to-end TCP latency into endhost and network delays, without requiring admin privileges. We validate that ELEMENT achieves more than 90% accuracy. To demonstrate ELEMENT’s potential impact on real-world applications, we implement a relatively simple user-level library that uses ELEMENT to minimize delays. For evaluation, we integrate ELEMENT with legacy TCP applications and show that it can reduce latency by up to 10 times while maintaining throughput and fairness. We finally demonstrate that ELEMENT can significantly reduce the latency of a virtual reality application.

Mobile data offloading


Adaptive video streaming


Data center resource disaggregation

Disaggregating resources in data centers is an emerging trend. Recent work has begun to explore memory disaggregation, but suffers limitations including lack of consideration of the complexity of cloud-based deployment, including heterogeneous hardware and APIs for cloud users and operators. In this research, we develop FluidMem, a complete system to realize disaggregated memory in the datacenter. Going beyond simply demonstrating remote memory is possible, we create an entire Memory as a Service. We define the requirements of Memory as a Service and build its implementation in Linux as FluidMem.