Describe the types of hubs.

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 Types of hubs: 

1) Passive 2) Active 3) Intelligent 

Passive Hubs: A passive hubs simply combines the signals of a network segments. There is no signal processing or regeneration. 

A passive hub reduces the cabling distance by half because it does not boost the signals and in fact absorbs some of the signal.

 With the passive hub each computer receives the signal sent from all the other computers connected to the hub.

Active hubs: They are like passive hubs but have electronic components for regeneration and amplification of signals.

 by using active hubs the distance between devices can be increased.

 The main drawback of active hubs is that the amplify noise along with the signals. They are also much expensive than passive hubs. 

Intelligent hubs: in addition to signal regeneration, intelligent hubs perform some network management and intelligent path selection. 

One advantage to this is that all transmission media segment can be connected permanently because each segment will be used only when a signal is sent to a device using that segment.

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