Networking & Internet

Hub

Definition

A network hub is a simple, older networking device that connects multiple computers or other network devices together. It operates at the physical layer (Layer 1) of the OSI model. When it receives a data packet, it broadcasts that packet to every other port on the hub.

Why It Matters

Hubs represent an early and simple way of creating a local network. Understanding them is important for historical context and to appreciate the efficiency of modern switches.

Contextual Example

In an old network using a hub, if Computer A wants to send data to Computer B, the hub sends that data to Computers C, D, and E as well. This creates unnecessary network traffic and can lead to "collisions" if multiple devices try to talk at once.

Common Misunderstandings

  • Hubs are considered obsolete and have been completely replaced by switches, which are much more intelligent and efficient.
  • A hub is a "dumb" device, whereas a switch is a "smart" device that learns which devices are on which ports.

Related Terms

Last Updated: December 18, 2025