AWS has made Resilient Network Graphs (RNG), a flat network architecture based on quasi-random graph theory, the default for most new non-GPU data center builds globally. Replacing traditional fat-tree topologies, RNG uses passive optical ShuffleBoxes to create quasi-random ToR-to-ToR mesh connections, eliminating spine and aggregation switch tiers entirely. The results: 69% fewer networking devices, up to 33% higher throughput, and a projected 40% reduction in network power equipment power consumption. A custom routing protocol called Spraypoint handles packet delivery across the hierarchy-free mesh. The design also offers graceful degradation — losing 1% of routers causes roughly 1% capacity loss rather than cascading failures. Validated through 530 processor-years of EC2 simulation and three production deployments in Europe, RNG became the default in April 2026. The architecture is limited to general-purpose compute; GPU clusters still use UltraServer due to their coordinated traffic patterns.
