What Are Ethernet Switches? | Wired LAN Basics

Ethernet switches connect multiple wired devices on a local network, forwarding data only to the intended destination port for efficient communication.

For the full breakdown, see our best Adaptateur Ethernet Switch guide.

An Ethernet switch is the backbone of any wired network. It expands the number of devices you can connect to your router, sending data only where it needs to go rather than broadcasting it everywhere. Here’s how they work, what types exist, and how to use one correctly.

How Ethernet Switches Work

A switch operates at the data link layer — Layer 2 — and functions as a MAC bridge. When data arrives, the switch reads the destination MAC address and forwards the packet only to the port connected to that specific device. This targeted delivery cuts down on unnecessary traffic and prevents collisions, which is the key advantage over older hubs.

For a home or small office, this means connecting a switch to a free port on your router instantly gives you more wired connections. Computers, printers, servers, wireless access points, and video-conferencing gear all benefit from the stable, low-latency link a switch provides.

Types of Ethernet Switches

Modular switches accept interchangeable line cards and power supplies, making them ideal for data centers and large enterprise networks. Fixed-configuration switches ship with a set number of ports and are what most homes and small businesses use.

You’ll also encounter two functional types: unmanaged and managed. Unmanaged switches are plug-and-play — connect them and they work. Managed switches add VLAN division, traffic statistics, port monitoring, Spanning Tree Protocol (STP), and link aggregation for controlling traffic flows in larger or more demanding networks.

Switch vs. Router vs. Hub

These three devices get confused constantly, but they solve different problems. A router connects networks — typically your home LAN to your internet service provider. A switch connects devices within a single network. A hub broadcasts every packet to every connected port, wasting bandwidth and causing collisions, while a switch sends each packet only to its intended recipient.

For most setups, the order is simple: modem feeds the router, and the router feeds the switch, which then distributes connections to your wired devices. If you’re expanding your wired network, a switch is always the right choice over a hub.

Setting Up an Ethernet Switch

Setup takes less than a minute. Connect one Ethernet cable from any port on your router to any port on the switch, then connect your devices — gaming consoles, desktop PCs, smart TVs, printers — to the remaining ports. The switch automatically learns which MAC addresses sit on which ports and forwards traffic accordingly.

The one caveat is that a switch serves wired devices only; it won’t extend your Wi-Fi coverage on its own. You’d need a wireless access point for that. Also, if you’re building a redundant network with multiple switch-to-switch links, make sure your switch supports STP to prevent loops that can destabilize the network.