Skip site navigation (1)Skip section navigation (2)
Date:      Sun, 27 Jul 2003 20:39:47 +1000
From:      Mark Hannon <markhannon@optusnet.com.au>
Cc:        freebsd-ipfw@freebsd.org
Subject:   Re: using dummynet to simulate modem, dsl, etc
Message-ID:  <3F23ABF3.1020905@optusnet.com.au>
In-Reply-To: <20030725103814.A54554@xorpc.icir.org>
References:  <3F212BF7.4060602@optusnet.com.au> <20030725103814.A54554@xorpc.icir.org>

next in thread | previous in thread | raw e-mail | index | archive | help
For those that are interested ... the following script and test results 
were obtained.  My
reasonings for the delay etc are partially included in the perl script. 

/mark


#!/usr/bin/perl
#
# $Id: lnf-test.pl,v 1.1 2003/07/27 10:30:57 mark Exp $
#

# =====================================================================
# Details of all of the networks to be simulated are stored in a hash:
#
# name =>         "descriptive text"
# ip =>         "dotted ip number - will be aliased to lo0",
# mtu =>         "mtu in octets",
# us_bw =>         "upstream bandwidth in kbit/s",
# us_queue =>     0,
# us_init_delay =>     "upstream processing delay only",
# us_total_delay =>     "upstream total delay - calculated",
# ds_bw =>         "downstream bandwidth in kbit/s",
# ds_queue =>     o,
# ds_init_delay =>     "downstream processing delay only",
# ds_total_delay =>     "downstream total delay - calculated",

$testnet = [
  { name =>         "56k modem",
    ip =>         "127.0.0.101",
    mtu =>         576,
    us_bw =>         33,
    us_queue =>     0,
    us_init_delay =>     40,     # V.90 processing, error correction etc.
    us_total_delay =>     0,
    ds_bw =>         56,
    ds_queue =>     0,
    ds_init_delay =>     40,     # V.90 processing, error correction etc.
    ds_total_delay =>     0 },
  { name =>         "128k ISDN-BA",
    ip =>         "127.0.0.102",
    mtu =>         576,
    us_bw =>         128,
    us_queue =>     0,
    us_init_delay =>     20,    # guesstimate
    us_total_delay =>     0,
    ds_bw =>         128,
    ds_queue =>     0,
    ds_init_delay =>     20,     # guesstimate
    ds_total_delay =>     0 },
  { name =>         "512k/64k ADSL",
    ip =>         "127.0.0.103",
    mtu =>         1500,
    us_bw =>         64,
    us_queue =>     0,
    us_init_delay =>     15,    # guesstimate
    us_total_delay =>     0,
    ds_bw =>         512,
    ds_queue =>     0,
    ds_init_delay =>     15,     # guesstimate
    ds_total_delay =>     0 },
  { name =>         "1500k/256k ADSL",
    ip =>         "127.0.0.104",
    mtu =>         1500,
    us_bw =>         256,
    us_queue =>     0,
    us_init_delay =>     15,    # guesstimate
    us_total_delay =>     0,
    ds_bw =>         1500,
    ds_queue =>     0,
    ds_init_delay =>     15,     # guesstimate
    ds_total_delay =>     0 },
  { name =>         "8000k/1000k ADSL",
    ip =>         "127.0.0.105",
    mtu =>         1500,
    us_bw =>         1000,
    us_queue =>     0,
    us_init_delay =>     15,    # guesstimate
    us_total_delay =>     0,
    ds_bw =>         8000,
    ds_queue =>     0,
    ds_init_delay =>     15,     # guesstimate
    ds_total_delay =>     0 },
];


# =====================================================================
# Loop through $testnet and setup simulated networks

$set_nr = 10;    # the initial ipfw set number to use
$pipe_nr = 10;    # the initial ipfw pipe number to use
$rule_nr = 10;  # the initial ipfw rule number to use

foreach $this (@$testnet){

  # add serilization of 40 octet ACK to upsteam delay
  $us_serial_delay = (40 * 8 ) / $$this{us_bw};
  $$this{us_total_delay} = int($$this{us_init_delay} + $us_serial_delay);

  # add serilization of MTU octet data to downstream delay
  $ds_serial_delay = ($$this{mtu} * 8 ) / $$this{ds_bw};
  $$this{ds_total_delay} = int($$this{ds_init_delay} + $ds_serial_delay);

  printf "%s: %s kbit/s @ %s ms down and %s kbit/s @ %s ms up\n",
    $$this{name},
    $$this{ds_bw}, $$this{ds_total_delay},
    $$this{us_bw}, $$this{us_total_delay};

  # add alias to lo0 for the address
  $ifconfig_command = "ifconfig lo0 alias $$this{ip}";
  print $ifconfig_command, "\n";
  `$ifconfig_command`;

  # setup an input pipe to simulate the upstream
  $ipfw_command = "ipfw -q add $rule_nr pipe $pipe_nr ip from any to 
$$this{ip} in";
  $pipe_command = "ipfw -q pipe $pipe_nr config bw $$this{us_bw}kbit/s " .
    "queue $$this{us_queue} delay $$this{us_total_delay}ms";
  print $ipfw_command, "\n";
  `$ipfw_command`;
  print $pipe_command, "\n";
  `$pipe_command`;
  $rule_nr++;
  $pipe_nr++;

  # setup an input pipe to simulate the downstream
  $ipfw_command = "ipfw -q add $rule_nr pipe $pipe_nr ip from $$this{ip} 
to any in";
  $pipe_command = "ipfw -q pipe $pipe_nr config bw $$this{ds_bw}kbit/s " .
    "queue $$this{ds_queue} delay $$this{ds_total_delay}ms";
  print $ipfw_command, "\n";
  `$ipfw_command`;
  print $pipe_command, "\n";
  `$pipe_command`;
  $rule_nr++;
  $pipe_nr++;

}

# SIGHUP inetd in order to listen on all new interfaces
`killall -HUP inetd`;

# =====================================================================
# Loop through $testnet and test performance

foreach $this (@$testnet){

  # print headers etc
  printf 
"===================================================================\n";
  printf "%s: %s kbit/s @ %s ms down and %s kbit/s @ %s ms up\n",
    $$this{name},
    $$this{ds_bw}, $$this{ds_total_delay},
    $$this{us_bw}, $$this{us_total_delay};
  printf 
"===================================================================\n";

  $start_time = time;
  $ftp_command = "fetch ftp://$$this{ip}/pub/test_small";
  printf "$ftp_command\n";
  `$ftp_command`;
  $finish_time = time;
  $clock_time = $finish_time - $start_time;
  printf "Clock time for transfer = $clock_time seconds\n";

  printf "\n";
}



tbird:~/projects/lnf-test# ./lnf-test.pl
56k modem: 56 kbit/s @ 122 ms down and 33 kbit/s @ 49 ms up
ifconfig lo0 alias 127.0.0.101
ipfw -q add 10 pipe 10 ip from any to 127.0.0.101 in
ipfw -q pipe 10 config bw 33kbit/s queue 0 delay 49ms
ipfw -q add 11 pipe 11 ip from 127.0.0.101 to any in
ipfw -q pipe 11 config bw 56kbit/s queue 0 delay 122ms
128k ISDN-BA: 128 kbit/s @ 56 ms down and 128 kbit/s @ 22 ms up
ifconfig lo0 alias 127.0.0.102
ipfw -q add 12 pipe 12 ip from any to 127.0.0.102 in
ipfw -q pipe 12 config bw 128kbit/s queue 0 delay 22ms
ipfw -q add 13 pipe 13 ip from 127.0.0.102 to any in
ipfw -q pipe 13 config bw 128kbit/s queue 0 delay 56ms
512k/64k ADSL: 512 kbit/s @ 38 ms down and 64 kbit/s @ 20 ms up
ifconfig lo0 alias 127.0.0.103
ipfw -q add 14 pipe 14 ip from any to 127.0.0.103 in
ipfw -q pipe 14 config bw 64kbit/s queue 0 delay 20ms
ipfw -q add 15 pipe 15 ip from 127.0.0.103 to any in
ipfw -q pipe 15 config bw 512kbit/s queue 0 delay 38ms
1500k/256k ADSL: 1500 kbit/s @ 23 ms down and 256 kbit/s @ 16 ms up
ifconfig lo0 alias 127.0.0.104
ipfw -q add 16 pipe 16 ip from any to 127.0.0.104 in
ipfw -q pipe 16 config bw 256kbit/s queue 0 delay 16ms
ipfw -q add 17 pipe 17 ip from 127.0.0.104 to any in
ipfw -q pipe 17 config bw 1500kbit/s queue 0 delay 23ms
8000k/1000k ADSL: 8000 kbit/s @ 16 ms down and 1000 kbit/s @ 15 ms up
ifconfig lo0 alias 127.0.0.105
ipfw -q add 18 pipe 18 ip from any to 127.0.0.105 in
ipfw -q pipe 18 config bw 1000kbit/s queue 0 delay 15ms
ipfw -q add 19 pipe 19 ip from 127.0.0.105 to any in
ipfw -q pipe 19 config bw 8000kbit/s queue 0 delay 16ms

===================================================================
56k modem: 56 kbit/s @ 122 ms down and 33 kbit/s @ 49 ms up
===================================================================
fetch ftp://127.0.0.101/pub/test_small
Receiving test_small (40960 bytes): 100%
40960 bytes transferred in 6.1 seconds (6.58 kBps)
Clock time for transfer = 8 seconds
 
===================================================================
128k ISDN-BA: 128 kbit/s @ 56 ms down and 128 kbit/s @ 22 ms up
===================================================================
fetch ftp://127.0.0.102/pub/test_small
Receiving test_small (40960 bytes): 100%
40960 bytes transferred in 2.7 seconds (15.06 kBps)
Clock time for transfer = 4 seconds
 
===================================================================
512k/64k ADSL: 512 kbit/s @ 38 ms down and 64 kbit/s @ 20 ms up
===================================================================
fetch ftp://127.0.0.103/pub/test_small
Receiving test_small (40960 bytes): 100%
40960 bytes transferred in 0.7 seconds (57.42 kBps)
Clock time for transfer = 1 seconds
 
===================================================================
1500k/256k ADSL: 1500 kbit/s @ 23 ms down and 256 kbit/s @ 16 ms up
===================================================================
fetch ftp://127.0.0.104/pub/test_small
Receiving test_small (40960 bytes): 100%
40960 bytes transferred in 0.3 seconds (126.33 kBps)
Clock time for transfer = 1 seconds
 
===================================================================
8000k/1000k ADSL: 8000 kbit/s @ 16 ms down and 1000 kbit/s @ 15 ms up
===================================================================
fetch ftp://127.0.0.105/pub/test_small
Receiving test_small (40960 bytes): 100%
40960 bytes transferred in 0.2 seconds (202.97 kBps)
Clock time for transfer = 1 seconds
 





Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?3F23ABF3.1020905>