Towards a high performance internet

Over the last 25 years, the Internet’s speed has increased at startling rates; still, researchers are making the Internet even faster. In fact, Dr. Brighten Godfrey, Assistant Professor at the University of Illinois, Urbana-Champaign is working to make the Internet as close as possible to the speed of light, the ultimate physical limitation.

Today, when people and machines interact across the network, even sending a small message and getting a reply can take significant time. That is what's called network latency. “Latency is the key challenge for our interactive experiences on the Internet, whether between people or computers," Godfrey said. "And today every millisecond matters.”  Network latency has an incredible impact on the ways that consumers choose to purchase goods on the web, play online games, or chat on a video conference. Yet the Internet today is commonly 30 times slower and often 100 times slower than what the speed-of-light limit should allow, even for simple tasks like retrieving the first small part of a web page.

Dr. Godfrey and his team work in several areas of networking, including high throughput data center networks to support big data analytics and cloud computing; network verification to fundamentally improve security and dependability of network infrastructure; and low-latency networking. Dr. Godfrey’s research interests, though fundamental in nature, have applications that are practically deployed as well. For example, his group’s Performance-oriented Congestion Control (PCC) project is now receiving interest from several major Internet content delivery services, and his work on network verification led to a venture-backed startup. And improvements in Internet latency may have a profound effect on the way we use the Internet.

Current research includes:

  • Causes of Latency: Dr. Godfrey and collaborators Ankit Singla and Prof. Bruce Maggs of Duke University are working to understand why the Internet is so far from the speed of light. This involves “measuring factors at every layer of the Internet,” says Dr. Godfrey, from the location of fiber optic cable and routers, to ISP’s business policies, to protocols used to transfer data. In doing so, he and his team are able to understand where the time goes and thus, can work towards minimizing that time.

  • Reducing Latency: Dr. Godfrey is developing tools to reduce latency in some of the Internet’s most important protocols. One method, developed by Ph.D. student Ashish Vulimiri, is to send requests to many servers at the same time and use the fastest answer that comes back. Although this technique increases server utilization, when used carefully it has nonetheless proven to be an effective way to reduce latency.

  • Performance-oriented Congestion Control (PCC): One of the main reasons for high latency is the TCP protocol, which is responsible for controlling data transmission rates for most communication on the Internet today. Students Mo Dong and Qingxi Li, along with collaborators at Hebrew University of Jerusalem, are taking on this project with PCC, which uses online learning algorithms to intelligently find the best strategies for data transmission. This smart technology allows for less reliance upon predefined assumptions that a programmer previously would have had to hardwire, leading to consistently high performance.


Dr. Brighten Godfrey is an assistant professor in the Department of Computer Science at the University of Illinois at Urbana-Champaign. He received his Ph.D. at UC Berkeley in May 2009, and his B.S. at Carnegie Mellon University in 2002. His research interests lie in the design of networked systems and algorithms. He is a winner of the Sloan Research Fellowship (2014), the National Science Foundation CAREER Award (2012), an Internet2 Innovative Application Award (2013), and paper awards from the IEEE Communications Society & Information Theory Society, the IEEE Communications Society Data Storage Technical Committee, and ACM HotSDN (2012 and 2014). He was a Beckman Fellow at the UIUC Center for Advanced Study in 2014-2015, and program committee co-chair of ACM HotNets 2014.

Dr. Godfrey originally started a career in research because he “loved the ‘safari’ of exploring” new ideas, designing and building new things. He found that computer networking was the perfect outlet for exploration and impact. As a young student, he enjoyed work that was mathematical yet had real applications. As his career continued to build, he has found ways to support research that encourages computer networks to bring people together in new ways.

Dr. Godfrey’s work is made possible by a highly collaborative team. Group members include doctoral students, Ankit Singla, the lead on the speed-of-light Internet project; Mo Dong, the lead on PCC; Ashish Vulimiri, Sangeetha Abdu Jyothi, Soudeh Ghorbani, and Qingxi Li, who lead other parts of the group’s work. Additionally, M.S. student Fan Yang and postdoctoral associate Anduo Wang commit their time and energy to Dr. Godfrey’s projects.

Alongside Dr. Godfrey’s team are many collaborators that bring perspective to his work. Collaborators include Prof. Bruce Maggs and students at Duke University, and Prof. Michael Schapira and students at Hebrew University of Jerusalem.



PCC: Re-architecting Congestion Control for Consistent High Performance


VeriFlow: Verifying Network-Wide Invariants in Real Time


Jellyfish: Networking Data Centers Randomly


Debugging the Data Plane with Anteater


Pathlet Routing



Alfred P. Sloan Research Fellow in Computer Science, 2014

National Science Foundation CAREER Award, 2012

Dean’s Award for Excellence in Research, UIUC College of Engineering, 2015

UIUC Engineering Council Outstanding Advisor, 2015

Ranked as Outstanding Teacher or Excellent Teacher in every semester of teaching since 2011