Beyond heat loss the other big way data center losses energy is when moving data around from rack-to-rack and server-to-server. I’ll discuss chip-to-chip solutions later. Networking was always an inefficiency, but frontier models require training across multiple racks and servers within racks and connections need to be high-bandwidth, low-latency, and low-power. The energy cost and time delay associated with moving data between compute nodes can be a significant bottleneck. The primary driver will continue to be for higher-bandwidth and lower latency connections, but if power consumption isn’t addressed networking could end up becoming one of the biggest energy loss components in the datacenter. For rack-to-rack improvements, silicon photonics-based AOCs and polymer optical fibers need to be explored, and for server-to-server it is co-packaged optics and wireless inter-rack communication.
Opportunities
Silicon photonics-based AOCs
Co-packaged optics (CPO)
Wireless inter-rack communication
Others
- Polymer Optical Fibers (POF) represent a cost-effective alternative to traditional glass fibers, leveraging perfluorinated graded-index polymer fibers with attenuation as low as 10 dB/km at 1300 nm. Current POF technologies support 100 Gbps, with ongoing research utilizing advanced modulation schemes like DMT (Discrete Multitone) pushing towards 400 Gbps over distances up to 100 meters, potentially offering a balance between performance and cost for certain data center applications.
- Software-defined networking (SDN) with AI-driven traffic management is emerging as a powerful tool for optimizing data center network performance, particularly for AI workloads. This approach enables dynamic resource allocation and intelligent routing based on real-time traffic patterns and application demands, potentially improving overall network efficiency and reducing congestion in AI-intensive environments.
- Coherent optics, traditionally used in long-haul telecommunications, are finding applications in data center interconnects for high-capacity, long-reach links. This technology enables higher spectral efficiency and longer transmission distances, potentially simplifying data center architectures and reducing the number of required optical-electrical-optical conversions.
- Passive optical circuit switching offers a low-power alternative to traditional electronic packet switching for certain data center traffic patterns. By using optical components to route entire wavelengths or fibers, this technology can potentially reduce power consumption and latency for large data transfers common in AI training workloads.