Executive Summary

In the rapidly evolving landscape of high-performance computing (HPC) and artificial intelligence, network infrastructure plays a crucial role in determining the efficiency and scalability of operations. This white paper introduces Lepton's cutting-edge Layer-1 (L1) switch solutions. These innovative switches are designed to meet the demanding requirements of modern data centers, AI training facilities, and high-performance computing environments.
Introduction

As data-intensive applications and AI workloads continue to grow in complexity and scale, the need for high-bandwidth, low-latency networking solutions has become paramount. Traditional network architectures often struggle to keep pace with these demands, creating bottlenecks that can significantly impact performance and productivity. Lepton's ColdFusion and LightFusion switches address these challenges head-on, offering unparalleled speed, flexibility, and scalability.

Advantages of L1 Switches for AI

L1 switches offer several benefits that make them particularly suitable for AI applications:

1. Low Latency: L1 switches provide extremely low latency, offering latencies under 15ns. This is crucial for AI workloads that require real-time processing and rapid data exchange between nodes.
2. High Bandwidth: AI workloads often involve large-scale data transfers. L1 switches can support high-bandwidth connections, capable of handling up to 256 ports of 100Gb links or up to 192 optical links capable of speeds of 800Gb or more. The total bandwidth supported per switch is 51.2Tb or 307.2Tb respectively.
3. Disaggregated Computing: L1 switches provide direct, high-speed connections between GPUs, storage, and compute resources, reducing bottlenecks and enabling dynamic resource allocation with zero added latency. This enhances performance, scalability, and efficiency in modern AI-driven data centers.

L1 Switches in AI Training Labs

Accelerating AI Development

L1 switches play a crucial role in AI training labs by enabling:

1. Flexible Network Configurations: L1 switches allow for programmable and remote access to the physical layer of a test lab infrastructure, eliminating the need for manual cabling configurations.
2. Equipment Sharing: Expensive AI training equipment can be shared more efficiently across different projects and teams, reducing capital expenditure.
3. Increased Test Velocity: By automating physical layer connections, L1 switches help accelerate service onboarding, testing of updates and patches, and the development of new AI services.

Enhancing AI Model Training

The scalability and high-performance characteristics of L1 switches make them ideal for AI model training:

1. Large-Scale Data Analysis: L1 switches efficiently manage massive datasets by providing ultra-low latency and high-bandwidth connections. This capability is essential for training complex AI models in fields like healthcare, finance, and scientific research, where rapid data transfer and real-time processing are critical for handling large volumes of information.
2. High-Performance Computing: L1 switches facilitate high-speed, low-latency connections between distributed computing resources, enabling complex AI tasks that might overwhelm traditional centralized systems. This efficient interconnectivity allows for better scalability and resource utilization in high-performance computing environments.

L1 Switches in Production AI Environments

Supporting Large-Scale AI Infrastructure

1. L1 switches play a critical role in optimizing both performance and cost in AI production environments by enabling high-speed, low-latency interconnects between disaggregated resources. By providing direct access to GPUs, CPUs, high-bandwidth memory (HBM), and NVMe storage, L1 switches facilitate flexible resource allocation and dynamic workload balancing. This ensures that compute-intensive tasks can be assigned to available resources without the need for overprovisioning, maximizing hardware utilization and reducing idle time.
2. In AI deployments leveraging key building blocks like NVIDIA’s GB200 NVL72 racks, Grace Hopper Superchips, and NVLink technology, L1 switches help reshape network topologies by enabling dynamic, on-demand resource pooling. This allows different users or workloads to access GPU clusters, memory pools, or storage arrays as needed, ensuring efficient scaling and workload distribution.
3. Furthermore, adaptive routing and traffic management capabilities in advanced L1 fabrics minimize network congestion, reducing latency and enhancing throughput for real-time AI inference and training tasks. The result is a cost-effective infrastructure that scales efficiently, reduces operational expenses, and maximizes performance for AI-driven applications across industries like healthcare, finance, and autonomous systems.

The Lepton ColdFusion: Redefining Layer 1 Switching

Key Features

The Lepton ColdFusion is a state-of-the-art OEO Layer-1 switch that sets new standards in performance and versatility:

• High-Density Ports: Supports up to 256 ports of wire-speed 100Gb Ethernet or 100Gb InfiniBand
• Flexible Media Support: Compatible with Single Mode, Multi-mode fiber, ACC, AEC and DAC
• Ultra-Low Latency: Fixed, deterministic latency of <15ns.
• Zero Insertion Loss: Maintains signal integrity across connections.

Benefits for Modern Infrastructure

• Increased Efficiency: Optimizes data flow and reduces network bottlenecks.
• Scalability: Easily adapts to growing network demands and evolving technologies.
• Reduced Operational Costs: Simplifies network management and reduces manual intervention.
• Future-Proofing: Supports emerging high-speed protocols and applications.
• Improved Performance: Enables faster data processing and reduced time-to-insight for data-intensive workloads.

Technical Specifications

• Chassis Options:
• 8-Slot Chassis (12RU): Up to 256 QSFP28 ports
• 2-Slot Chassis (4RU): Up to 64 QSFP28 ports
• Port Speeds: Up to 100GbE or 100Gb InfiniBand
• Power: Redundant, hot-swappable AC power supplies
• Management: CLI, SSH, Python API, RESTful API

The Lepton LightFusion: Optical Switching for Next-Generation Networks

Key Features

The LightFusion series, based on the Optical Switch Platform (OSP), represents the next evolution in optical switching:

• High-Density Optical Ports: Up to 192 ports operating at 100Gb-800Gb and higher.
• MEMS Technology: Utilizes advanced Micro-Electro-Mechanical Systems for reliable, non-blocking all-optical matrix switching.
• Ultra-Low Optical Loss: Ensures minimal signal degradation across the network.
• Protocol and Rate Independence: Supports any optical protocol and data rate.
• Compact Design: High port density in a space-efficient form factor.
• Energy Efficient: Reduces power consumption compared to traditional switching solutions.

Technical Specifications

• Models: OSP-96 with 96x96 non-blocking connectivity, OSP-192 with 192x192 non-blocking connectivity
• Switching Speed: Lightning-fast reconfiguration for dynamic network environments
• Scalability: Designed for easy expansion in carrier and enterprise networks

Conclusion

As the demands on network infrastructure continue to intensify, particularly in AI and high-performance computing environments, the need for advanced switching solutions becomes increasingly critical. Lepton's ColdFusion and LightFusion switches represent the cutting edge of Layer-1 and optical switching technology, offering unparalleled performance, flexibility, and scalability.

By implementing these innovative solutions, organizations can significantly enhance their network capabilities, streamline operations, and position themselves at the forefront of technological advancement. As we move into an era of even more data-intensive applications and AI-driven innovations, Lepton's switching solutions provide the foundation for building robust, future-ready network infrastructures.

Citations

1. Lepton’s product line up: https://www.leptonsys.com/products
2. AI Scale-Up and Memory Disaggregation: https://ayarlabs.com/blog/ai-scale-up-and-memory-disaggregation-two-use-cases-enabled-by-ucie-and-optical-io
3. Deep Dive: Data Center Networking: https://deepfundamental.substack.com/p/deep-dive-data-center-networking
4. Networks for High-Performance Computing: https://louisjenkinscs.github.io/survey/Networks_for_High-Performance_Computing.pdf
5. NVidia NVLINK Overview: https://www.nvidia.com/en-us/data-center/nvlink