Expander Datacenters: From First Principles to the Cloud

Speaker: Prof. Michael Schapira, Hebrew University of Jerusalem
Series: Computer Laboratory Systems Research Group Seminar

Abstract:

AWS recently adopted an expander-based network topology as the default design for its new datacenters, bringing an idea rooted in graph theory into operation at unprecedented scale. In this talk, we trace the research journey that led to this development. We begin with early work on random datacenter topologies and then discuss our work on identifying expansion as the underlying design principle, showing that any expander network can offer superior throughput, resilience, and cost efficiency. Next, we examine two persistent challenges in turning this principle into a practical architecture, cabling and routing, and the ideas developed to address them. Along the way, we will see how graph theory illuminates concrete systems problems and reveals deep connections between seemingly different points in the datacenter network design space.

Bio:

Michael Schapira is a professor of Computer Science at the Hebrew University of Jerusalem and a visiting researcher at the University of Cambridge. His research interests include network architectures and algorithms, applications of machine learning to systems, and unorthodox hardware.

Online meeting link:

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