A central hub, in the context of networking, refers to a device or component that serves as a central point of connectivity and communication for multiple devices in a network. The central hub facilitates data transmission between devices by receiving data from one device and broadcasting it to all other devices connected to the hub.
Key characteristics of a central hub include:
- Connectivity: The central hub provides ports or connections where network devices, such as computers, printers, or other peripherals, can be connected.
- Data Distribution: When one device sends data to the central hub, the hub broadcasts the data to all other devices connected to it. This means that data is received by all devices, regardless of the intended recipient.
- Simplicity: Central hubs are simple devices with minimal intelligence. They don’t perform any processing or filtering of network traffic.
- Shared Bandwidth: Since all data is broadcast to all devices, the bandwidth available on the network is shared among all connected devices. This can lead to congestion and reduced network performance as the number of connected devices increases.
- Single Point of Failure: A central hub is a single point of failure in the network. If the hub malfunctions, the entire network can be affected.
- Collision Domain: In Ethernet networks, all devices connected to a central hub share the same collision domain. This means that if two devices transmit data simultaneously, a collision can occur, leading to data retransmissions and potential delays.
- Limited Intelligence: Central hubs lack the ability to intelligently manage network traffic or prioritize data. They simply repeat data to all connected devices.
It’s important to note that central hubs have become less common in modern networks due to their limitations in terms of network performance, scalability, and security. Ethernet switches, which offer features like dedicated bandwidth per port and better collision domain management, have largely replaced hubs in most network setups. Switches are able to direct data only to the intended recipient, improving network efficiency and reducing unnecessary traffic.