The Relationship Between Switches, Network Protocols, and AI in Modern Data Centers

Network protocols define the rules for data exchange; the OSI seven‑layer model is the internationally recognized standard.

For HPC and AI workloads, the demand for high throughput and low latency drives a transition from traditional TCP/IP to RDMA technologies, including InfiniBand, RoCE, and iWARP.

RDMA (Remote Direct Memory Access) allows direct memory reads/writes over the network without kernel involvement, dramatically reducing latency and CPU overhead.

Switches operate at the data‑link layer, forwarding frames based on MAC addresses, while routers work at the network layer using IP addressing.

Traditional three‑tier data‑center networks (access‑aggregation‑core) suffer from bandwidth waste, large fault domains, and increased latency; leaf‑spine architectures flatten the topology, provide non‑blocking bandwidth, and improve fault tolerance.

NVIDIA’s Spectrum and Quantum platforms target AI workloads: Spectrum‑X combines high‑speed Ethernet with RoCE to maximize NCCL performance for generative AI, while the SuperPOD architecture leverages InfiniBand and NVLink for massive AI clusters.

The switch market remains dominated by Ethernet, but InfiniBand retains a niche in large‑scale compute; major players include Cisco and Arista for Ethernet, and Mellanox (now part of NVIDIA) for InfiniBand.

Market data shows strong growth in Ethernet switch revenue and port shipments, especially for 200 G/400 G products, indicating a shift toward higher‑speed, AI‑ready networking solutions.