Test Download Speed with Wireshark

It sure would be helpful to find out what actual network/bandwidth speed is versus relying on other tools.

Utilize Wireshark to monitor your network card to get an accurate representation of your bandwidth.

If you have a trace running as you download a file go to Statistics - IO Graph draw a graph in the outbound direction only. Change the Y-axis to bits/tick if you want to see bandwidth.

Maybe you are using a Linux system or just like using tcpdump.  TCPdump doesn't give you the real-time stats but you can feed it's output to something that does.

$ sudo tcpdump -i eth1 -l -e -n | ./netbps

tcpdump

: verbose output suppressed, use -v or -vv for full protocol decode

listening on eth1

, link-type EN10MB (Ethernet), capture size 96 bytes

11:36:53 2143.33 Bps

11:37:03 1995.99 Bps

11:37:13 2008.35 Bps

11:37:23 1999.97 Bps

11:37:33 2083.32 Bps

131 packets captured

131 packets received by filter

0 packets dropped by kernel

You'd need to add a suitable filter expression at the end of the tcpdump command to only include the traffic generated by your app (e.g. port 80)

The program netbps is this:

#!/usr/bin/perl

use strict

;

use warnings

;

use

Time::HiRes;

my $reporting_interval

= 10.0; # seconds

my $bytes_this_interval

= 0;

my $start_time

= [Time::HiRes::gettimeofday()];

while (<>) {

if (/ length (\d+)) {

$bytes_this_interval

+= $1;

my $elapsed_seconds

= Time::HiRes::tv_interval($start_time);

if ($elapsed_seconds > $reporting_interval) {

my $bps

= $bytes_this_interval / $elapsed_seconds;

printf

"%02d:%02d:%02d %10.2f Bps\n", (localtime())[2,1,0],$bps;

$start_time

= [Time::HiRes::gettimeofday()];

$bytes_this_interval

= 0;

}

}

}

It's just an example, adjust to taste.