Understanding Switches: Types, Architecture, and Market Trends

What Is a Switch?

A switch is a multi‑port network device based on Ethernet that forwards data frames between hosts or network nodes according to the hardware (MAC) address contained in each frame. It functions like a specialized computer, connecting servers, PCs, IP phones, cameras, printers, and other endpoints, and interlinking with other switches, wireless access points, and routers to build a complete network.

Classification of Switches

By role in the network: core switch, aggregation (distribution) switch, access switch.

By coverage: WAN switch, LAN switch.

By port architecture: fixed‑port switch, modular switch.

By speed: 100 M, 1 G, 10 G, 100 G, etc.

By application scale: enterprise‑grade, campus‑grade, departmental, work‑group, desktop‑type.

By management capability: managed (network‑managed) switch, unmanaged (non‑managed) switch.

Network Deployment Scenarios

In campus networks, two main topologies are used: traditional Ethernet networking (core → aggregation → access) and passive optical networking, where the aggregation layer is replaced by an OLT and the access layer by ODN devices (splitters) serving ONUs. In enterprise environments, core switches act as aggregation points for uplinks, while access switches provide connectivity to end devices. Data‑center networks increasingly adopt a leaf‑spine architecture, where spine switches replace the traditional core layer and leaf switches replace the access layer, delivering higher bandwidth utilization, better scalability, lower latency, reduced deployment and maintenance costs, and improved reliability.

Industrial Switches

Industrial switches are engineered for harsh environments—high temperature, waterproof, explosion‑proof, vibration‑resistant, and electromagnetic‑interference‑tolerant. They must offer long service life, high cost‑performance, real‑time communication, network security, flexible topology, and easy deployment, serving sectors such as smart grids, smart factories, smart cities, rail transit, petrochemical, and renewable energy.

Switch Components

Typical Ethernet switch hardware consists of switching ASICs (the core chip), CPUs, PHYs, PCBs, optical modules, connectors, passive components, and chassis. Modern ASICs may integrate CPU and PHY functions, providing high‑throughput packet processing and complex forwarding logic.

White‑Box vs Black‑Box Switches

Traditional black‑box switches are closed‑source hardware and software, resulting in low interoperability, high operational complexity, and limited upgrade paths. White‑box switches decouple the hardware platform from the network operating system, offering up to 50 % lower acquisition cost, simpler deployment, advanced management, higher automation, and greater customization—key advantages for large‑scale data‑center expansion.

Market Drivers and Challenges

Emerging applications such as virtual reality, remote control, autonomous driving, and ultra‑HD video dramatically increase traffic, accelerating data‑center construction and initiatives like “East‑Data‑West‑Compute.” The market is driven by the need for high stability, performance, controllability, and low OPEX. While both self‑developed and commercial switch ASICs coexist, commercial chips are expected to dominate future growth due to higher R&D costs, long product lifecycles (8‑10 years), and geopolitical risks affecting custom chip supply.