Channel utilisation

Question

I am having problems calculating channel utilization. The question at hand reads as follows:

An application using TCP and will send data in windows of 64000 bytes over a 100 Mbit/s link. The round-trip time is 20ms and transmission times can be neglected.

What channel utilization can be achieved here?

 I thought I might calculate the channel utilization as follows:

channel utilization = windows size / (Bandwidth * RTT)

but I am unsure if this is the correct way. Any help would be greatly appreciated.

Answer 1

yes your way of solving is correct just be careful for units .....

we had given :

length of data = 64000 byte = 64000*8 bits

bandwidth  = 100 mbps = 100*10^6 bits per sec

rtt = 20ms = 20*10^-3sec

efficiency = transmission time / rtt

                 =length of data / (bandwidth * rtt)

                 =64000*8/(100*10^6*20*10^-3)

                 =0.256

efficiency in pecentage = 25.6 percent