iftop - display bandwidth usage on an interface by host


Right Part:

foo.example.com  =>  bar.example.com      1Kb  500b   100b
                 <=                       2Mb    2Mb    2Mb

The right part, indicates that 
the rate at which data has been sent and received over the preceding 2, 10 and 40 second intervals

Bottom Part:

TX:    cumm:   575KB   peak:   35.6Kb            rates:   9.61Kb  8.37Kb  5.83Kb
RX:            120KB           3.78Kb                      688b   2.26Kb  1.45Kb
TOTAL:         695KB           39.1Kb                     10.3Kb  10.6Kb  7.28Kb

TX is send, RX is receive
comm is the total, peak is the top rate over last 40s
rates indicate the rate average of 2s, 10s, 40s

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