I am a Ph.D. candidate in the Computer Science Department at Carnegie Mellon University, and I expect to graduate in the spring of 2017. I am advised by Vyas Sekar and Hui Zhang. Before CMU, I received Bachelor in Computer Science from Yao Class at Tsinghua in 2011.

My research interests include computer networks, distributed systems, big data, and cloud computing.

I will be joining UChicago CS as an assistant professor in Fall 2018.
[Curriculum Vitae] [Research Statement]

Thesis Research

The vision of my research is to optimize complex networked systems by machine learning techniques. While my thesis demonstrates the potential of this approach in improving the quality of Internet applications, there could be many innovations in this new space.

Motivation: Today’s Internet is dominated by applications such as video streaming (e.g., Netflix counts for 37% of Internet traffic) and VoIP (e.g., Skype users spend over 2 billion minutes talking to each other every day). With revenues of these applications critically depend on user engagement, it is crucial to maintain high user-perceived Quality of Experience (QoE) for these applications.

Approach: My dissertation demonstrates that data-driven techniques can improve Internet QoE by utilizing a centralized real-time view of performance across millions of clients. My thesis work has three key pieces:

Impact: CFA and VIA have been used in industry by Conviva and Skype, companies that specialize in QoE optimization for video streaming and VoIP, respectively.

Other Selected Projects

FESTIVE

[CoNEXT '12] "Improving Fairness, Efficiency, and Stability in HTTP-based Adaptive Video Streaming with FESTIVE" J. Jiang, V. Sekar, H. Zhang (Best Paper Runner-up, Fast-tracked to IEEE/ACM Transaction on Networking)

Conventional wisdom has been that TCP can ensure fairness among the video sessions sharing bottleneck links, but my research showed otherwise: these sessions could suffer from unfair, unstable quality, and inefficient bandwidth utilization, due to the behaviors of video streaming protocols. Building on this observation, I developed FESTIVE, the first HTTP-based video player that simultaneously improved fairness, stability, and efficiency over many commercial players. FESTIVE has inspired enormous work in industry and academia to further improve along these metrics.

EONA

[HotNets '14] "EONA: Experience-Oriented Network Architecture" J. Jiang, V. Sekar, X. Liu, I. Stoica, H. Zhang

Ecosystems of Internet applications are complex and federated. While any subsystem on the delivery chain, such as Comcast and Akamai, can impact end-to-end QoE, most of these subsystems cannot directly observe the impact on QoE as they change their configurations. This creates great room for improvement by aligning these subsystems with the end-to-end application QoE. Experience-Oriented Network Architecture (EONA) aims at bridging this gap by letting all subsystems along the delivery path be aware of the end-to-end QoE.

Recent Publications

A complete list of my publications is in CV.

Click here for earlier publications, journal articles, and technical reports.