iftop

iftop receives its name from the top command. This command displays the bandwidth usage of host for the past 2 seconds, 10 seconds and 40 seconds. It displays the contents on the basis of high bandwidth consumption to low band width consumption with which we can easily find the host which uses more bandwidth and avoid collisions.This command can be executed only in root privilege. With this command, one can view the to and fro of traffic from a specific network.