What is a hub ? A hub is a hardware element for centralizing network traffic coming from multiple hosts, that also propagates the signal. It has a certain number of ports - enough ports to link machines to one another, usually 4, 8, 16 or 32. Its only goal is to recover binary data coming into a port and send it to all the other ports. As with a repeater, a hub operates on layer 1 of the OSI model. This is why it is sometimes called a multiport repeater. The hub connects several machines together, sometimes arranged in a star shape, which gives it its name, due to the fact that all communication coming from the machines on the network passes through it. .
It is possible to connect several hubs together in order to centralize a larger number of machines. This is sometimes called a daisy chain. To do this, all you need to do is to connect the hubs using crossover cable. This kind of cable links the in/out ports on one end to those on the other.
Hubs generally have a special port hub called an uplink for connecting two hubs together using a patch cable. There are also hubs which can cross or uncross their ports automatically depending on whether they are connected to a host or to a hub.
|Up to three hubs can be chained.|
If you want to connect multiple machines to your Internet connection, a hub is not enough. You'll either need to have a router or a switch, or to leave the computer connected directly as a gateway (it will stay on constantly for as long as the other computers on the network want to access the Internet.)