George Varghese is a Principal Researcher at Microsoft Research. Before joining MSR's lab in Silicon Valley in 2013, he was a Professor of Computer Science at the University of California San Diego, where he led the Internet Algorithms Lab and also worked with the Center for Network Systems and the Center for Internet Epidemiology. He is the author of the textbook Network Algorithmics published by Morgan Kaufmann in 2004.
Before his Ph.D., George spent several years as part of the network architecture and advanced development group at Digital Equipment Corporation, where he wrote the first specification for the first transparent bridge architecture. After several iterations and other authors, this became the IEEE 802 bridge specification, a widely implemented standard that is the basis of the billion dollar transparent bridging industry. He was also part of the DEC team that invented the Gigaswitch and the Giganet.
Network algorithmics
Varghese is best known for helping define network algorithmics, a field of study which resolves networking bottlenecks using interdisciplinary techniques that include changes to hardware and operating systems as well as efficient algorithms. Among his contributions to network algorithmics are Deficit Round Robin, a scheduling algorithm that is widely used in routers, and timing wheels, an algorithm for fast timers that is used as the basis of fast timers in Linux and FreeBSD.
IP lookup and packet classification
Varghese has also worked extensively on fast IP lookup and packet classification. His work with G. Chandranmenon on Threaded indexes predates the work done at Cisco Systems and Juniper Networks on tag switching. His work on multibit tries has been used by a number of companies including Microsoft. His work on scalable IP packet lookup for longer addresses such as IPv6 is being considered for use by Linux. George also worked with Eatherton and Dittia on the Tree bitmap IP lookup algorithm that is used in Cisco’s CRS-1 router, which many believe to be the fastest router in the world. Tree bitmap and hypercuts appear to be among the best algorithms for IP lookup and packet classification today.
Self stabilization
George is also known for his contributions to the theoretical field of self-stabilization, where he has helped pioneer several general techniques such as local checking, local correction, and counter flushing.
NetSift
Varghese co-founded NetSift Inc. in 2004, serving as President and CTO. NetSift helped pioneer the notion of automated signature extraction for security and helped to introduce the use of streaming algorithms for network measurement and security at speeds greater than 10 Gbit/s. His work with Cristian Estan on multistage filters has been widely used in industry. NetSift was acquired in June 2005 by Cisco Systems as part of the Modular Switching Group.
2014 Koji Kobayashi Award for Computers and Communications for "Contributions to the field of network algorithmics and its applications to high-speed packet networks"
