AWS Replaces Fat-Tree Data Center Networks with Random Graph Theory, Cutting Routers by 69%

Steef-Jan Wiggers — Thu, 04 Jun 2026 08:25:00 GMT

AWS disclosed that Resilient Network Graphs, a flat network architecture based on quasi-random graph theory, is now the default for most new data center builds. The design replaces fat-tree hierarchies with direct ToR-to-ToR mesh connections using passive optical ShuffleBoxes, cutting routers by 69%, boosting throughput by 33%, and reducing network power consumption by 40%.

By Steef-Jan Wiggers

InfoQ - Amazon Web Services

AWS Replaces Fat-Tree Data Center Networks with Random Graph Theory, Cutting Routers by 69%