1. What is attenuation?
Attenuation refers to the weakening of the signal as it travels over cable. It is sometimes referred to as roll off.
As a signal travels across wire, its square wave becomes deformed in proportion to the distance traveled. Thus, attenuation is primarily a function of cable length. If the signal travels too far, it can degrade so much that the receiving station may not be able to interpret it and communication will fail.
A repeater is can be used to boost signal strength on a baseband network so that it can travel greater distances. An amplifier performs the same function on a broadband network.