A repeater is basically a device that amplifies a signal being transmitted on the network.
You can also say that repeater is a network device used to regenerate, replicate, and amplify the coming signal and then send that regenerated, replicated, amplified signal forward.
Repeater is used in long network lines, which exceed the maximum rated distance for a single run.
Repeater can regenerate or amplify both digital and analog signal.
Here there is a difference in regeneration and amplification. In case of amplification, if there is a impurity in coming signal then that signal can also be amplified. And in case of regeneration, if there is a impurity in coming signal, then there is an extraction of impurity from the coming signal and then amplified or reconstructed to send the signal forward.
Repeater works on layer 1 of OSI model.
If we place in OSI model, then they works on physical layer. It means, repeater receives the data in 0 and 1 form and amplified the as it is data to send forward.
Over distance, the cables connecting a network lose the signal transmitted. If the signal degrades too much, it fails to reach the destination. Or if it does arrive, the degradation of the message makes it useless.
Repeaters can be installed along the way to ensure that the data packets reach their destination.
There are two types of repeaters, listed here:
Digital repeaters amplifies the incoming signals and removes the impurity and then reconstruct the signal to send the signal forward.
Digital repeaters sends the signal in original quality.
Analog repeaters only amplifies the signals.