What are network Backbones? What are the four different backbone devices?


The devices which interconnect the various pieces of a network are called as backbones, signal transfer and data flow are assisted with these devices.

Network backbones are designed to maximize the reliability and performance of large-scale, long-distance data communications. A backbone could connect LAN ( local area network ) and WAN ( wide area network) together.

There are four types of backbones used in computer networking.

  • Hub

  • Bridge

  • Switch

  • Gateway


Hubs are centralized connecting devices, connected at the center of the star connection network. All devices connected to a network hub share all available bandwidth equally.

There is a possibility of colliding data send by two computers simultaneously. So in a hub network, data should send by a Pc only after completing earlier data transfer.

There are two types of Hubs

  • Active hubs: repeat and strengthen incoming transmissions. They are also sometimes referred to as repeaters

  • Passive hubs: simply serve as a point of connectivity, without any additional capabilities.

Bridge :

Bridges are smart devices, which track information on network traffic.

Bridges record traffic information and then uses this information to determine the easiest path to data transfer without having sent to every PC.

Bridges learn which addresses are on which network and develop a learning table so that subsequent messages can be forwarded to the right network.


Switches use package switching and full-duplex devices.

In this type of networking, more than one transmission is done at a time.

Switches eliminate the possibility of data collision, so switches allows data flow simultaneously in both direction


Gateway serves entry and exit point of a network.

Gateway connection can provide a connection between a computer on ethernet connection and PLC network, which are in two kinds of network protocol. This two network cannot have a connection directly. Gateway provides this connection and allow them to work together.