NetFridgeS: Enabling Dynamic Frequency Scaling on Network Switches through Carbon-Aware Routing

High performance network switches are designed to meet peak throughput demands, always operating at maximum clock frequency to avoid packet drops. However, real-world network traffic exhibits clear periodic patterns, leading to a waste of energy due to over-provisioning during non-peak hours. Dynamic frequency scaling, a popular energy saving mechanism, was not adopted by network switches due to differences in architecture from CPUs and the requirement not to drop packets. In this paper, we present NetFridgeS, enabling dynamic frequency scaling on high-performance network switches. NetFridgeS builds upon carbon-aware routing to forecast network utilization and adjust pipeline frequency. NetFridgeS is prototyped on FPGA using three distinct pipeline architectures, with sub-microsecond frequency switching times and minimal latency and resource overhead. By scaling down the frequency, NetFridgeS achieves an average energy saving of 77.74% at minimum throughput. In real network topologies, the combination of NetFridgeS and carbon-aware routing results in up to a 22.11% reduction in overall energy consumption and a 27.76% reduction in carbon emissions compared with current network deployments.