I am an Assistant Professor in the Computer Science Department at the University of Southern California. With my colleagues Ramesh Govindan and Minlan Yu, I run a networking and systems research group. My primary interests are in networks and distributed systems. My research goal is to design novel systems and protocols to dramatically improve Internet reliability and performance. I look to the needs of operators and providers to find challenging problems to attack. I use rigorous network measurements to understand the problems. Based on the problems' characteristics that I discover with the measurements, I design real, scalable systems to address the problems, aid operators, and improve the Internet.
In 2012, I completed my Ph.D. in the Department of Computer
Science at the
University of Washington, advised by
Tom Anderson and
Arvind Krishnamurthy. For my dissertation, I built systems that can help service providers improve Internet availability and
performance and that are deployable on today's Internet. After that, I worked for half a year at Google's Seattle office, as part of a great team tasked with making the mobile web fast. I greatly enjoyed the opportunity and learned a lot.
Research Projects
| 2010- | LIFEGUARD (Failure Isolation and Avoidance): A system to locate persistent Internet failures, coupled with protocol-compliant BGP techniques to force other networks to reroute around the failure. |
| 2008- | Reverse traceroute: A system to measure the path taken by an arbitrary destination to reach the user, without control of the destination. Addresses a limitation of traceroute, the most used Internet troubleshooting tool. |
| 2007- | Hubble: A system that identifies Internet black holes on a global-scale in real-time. Additionally, the system localizes and classifies the causes to aid network operators in fixing them. |
| 2007-2008 | Secure and Robust Internet Routing: Consensus routing, an approach to Internet routing based on classical distributed systems techniques. It eliminates virtually all routing failures associated with routing protocol convergence. |
| 2007- | iPlane: A system to estimate the path and performance between arbitrary Internet hosts. iPlane issues measurements to understand routing and performance, uses the measurements to build a compact 7MB atlas that encodes routing policies and preferences, then uses the atlas to predict unmeasured paths. |
| 2005-6 | IP Geolocation: A measurement-based technique to estimate the geographic location of arbitrary Internet hosts. Our approach produced estimates that were three times more accurate than those of existing techniques. |