so I'm reading this and I really don't understand. The standard ethernet, for instance 10Base5 , can only send data from one station to another station at a time which means it's half-duplex, but if it's half-duplex it should take all the bandwidth to send data without sharing to other stations and why does the example in the book raise down the bandwidth from 10Mbps to 5Mbps I don't understand

 

Hi

The document means that when only one station is transmitting and receiving to another station, the full 10 megabits is available. The half duplex means that only one of the stations can transmit at a time. When only one station transmits, it gets to use the full 10Mb bandwidth. However, if more than one station needs to transmit (two stations for example), time using the ethernet medium (cable) has to be "shared" between the two transmitting stations. A simple way to estimate the max bandwidth is to determine the average utilization for all stations. So, the average utilization estimate for two stations is 5 Mb. Its not very accurate, just a way to quickly estimate the max bandwidth.

eT