A hub, also called a network hub, is a common connection point for devices in a network. Hubs are devices commonly used to connect segments of a LAN. The hub contains multiple ports. When a packet arrives at one port, it is copied to the other ports so that all segments of the LAN can see all packets.
What Hubs Do
Hubs and switches serve as a central connection for all of your network equipment and handles a data type known as frames. Frames carry your data. When a frame is received, it is amplified and then transmitted on to the port of the destination PC.
Image: Hub and wireless hub network icons
In a hub, a frame is passed along or “broadcast” to every one of its ports. It doesn’t matter that the frame is only destined for one port. The hub has no way of distinguishing which port a frame should be sent to. Passing it along to every port ensures that it will reach its intended destination. This places a lot of traffic on the network and can lead to poor network response times.
Compared to a standard switch, the hub is slower as it can send or receive information just not at the same time, but typically costs more than a hub.
Passive, Intelligent and Switching Hubs
A passive hub serves simply as a conduit for the data, enabling it to go from one device (or segment) to another. So-called intelligent hubs include additional features that enables an administrator to monitor the traffic passing through the hub and to configure each port in the hub. Intelligent hubs are also called manageable hubs.
A third type of hub, called a switching hub, actually reads the destination address of each packet and then forwards the packet to the correct port.
Home and Small Business Hubs
Hubs can be used as a standalone device or connected to compatible hubs and switches to form a larger network. Hubs are generally easy to install and maintain, making these devices a good option for home networking. A hub is also easily configured for small business branch office networking.
Recommended Reading: The Difference Between Hubs, Switches and Routers.