NEWUDPL

NAME

newudpl - Network Emulator With UDP Link

SYNOPSIS

newudpl [-[v|vv]] [-p [recv_port]:[send_port]] [-i sorce_host[[:|/][port|*]]] [-o dest_host[[:|/]port]] [-s link_speed] [-d delay] [-e Ethernet_speed] [-q queue_buf_size] [-B bit_error_rate] [-L random_packet_loss_rate] [-O out_of_order_rate]

DESCRIPTION

This is a tool to create various condition of packet switching behavior artificially for UDP packets.

The emulator receives UDP packets on a designated port and then delays them, drops some randomly, corrupts the content, swaps the order of sending and emulates a finite-bandwidth link by queuing packets. It should be useful to examine an efficiency of network protocols or codecs.

INSTALLATION

Source codes are available from:
http://www.columbia.edu/~at541/src

To build, unpack the tar file, then type:

./configure make
I have only tested on SunOS 5.7, 5.8 system and Linux but it should compile on other Posix-compliant platforms.

OPTIONS

-v

-vv

Verbose output.
With a single -v,
the information of dropping packets by congestion and creating
random packet loss/bit error/out of order will be displayed;
with a second one, receiving and sending packets will also be shown.

-p receiving port : sending port

Specifies the binding ip-port for receiving and sending UDP packets. Otherwise, default values will be used.

Available range: 1024 - 65535 or 0x400 - 0xFFFF
Default: receiving 41192, sending 41193

-s emulating link speed

Specifies a finite-bandwidth. The speed of Transferring UDP packets will not exceed this speed. Unit is in kb/s.

Available range: 1 - 50000(MAX_KBPS)
Default: 1000

-e Ethernet speed

Specifies a Ethernet speed on the machine. It is used to calculate a tranmission delay, which makes difference especially when the emulating link speed is slow.

Available range: 1 for 10M, 2 for 100M, 3 for Gigabit Ethernet
Default: 10M(b/s)

-d delay

Specifies delay time. All the packets will have minimum delay. The deley for each packet could be varies, depenging on the link speed.
For example, -d2 is 2 (sec) and -d1.345678 is 1.345678 (sec).

Available range: 0 - 10(MAX_DELAYSEC)
Default: 0

-q queue-buffer size

Specifies the size of queueing buffer for receiving packets. If you large this number less likly to have congestion packet loss for the same link speed.

Available range: 1 - 16384 or 0x1 - 0x4000(MAX_QBUFSIZE)
Default: 8192

-i source host [[ : | / ] port | * ]

Specifies the source host for receiving packets. If the emulater receives a packet from a different host then the packet will be rejected. The host name could be either IP number with dotted-decimal notation (e.g., 128.59.16.8) or the host name (e.g., cs.columbia.edu). If the port is not sepcified then it will accept only packets from the the port 41191, default values, with corrsponding source host, but you could rule out this checking by using '*'.

Default: host - localhost, port 41191
Example,

-i dynamo.cs.columbia.edu/32768 -i dynamo.cs.columbia.edu/0x8000
-> accepts packets only from dynamo.cs.columbia.edu/32768

-i diamond.cs.columbia.edu
-> accepts packets only from diamond.cs.columbia.edu/41191

-i 128.59.16.7:*
-> accepts packets any port from disco.cs.columbia.edu (128.59.16.7)

-o destination host [[ : | / ] port ]

Specifies a destination host for outgoing packets.

Default: host - localhost, port 41194

-B bit error rate

Specifies a rate of genarating bit errors for outgoing packets. The rate is in 1/100000(BITERRDENOM).

Available range: 1 - 99999(BITERRDENOM - 1)
Default: 0

-L random packet loss rate

Specifies a rate of genarating random packet loss for outgoing packets. The rate is in percentage.

Available range: 1 - 99
Default: 0

-O out of order rate

Specifies a rate of randomizing oreder of packets. The distination host will receive some packets in out of order in certain rate. The rate is in percentage.

Available range: 1 - 99
Default: 0

USAGE

To create condition under following parameters,

from: dynamo.cs.columbia.edu(128.59.16.4)/41191
to: disco.cs.columbia.edu(128.59.16.7)/41194
link speed : 50(kb/s)
delay : 2.004000(sec)

type,

newudpl -idynamo.cs.columbia.edu -odisco.cs.columbia.edu -s50 -d2.004

For,

verbose mode
from: any port of dynamo.cs.columbia.edu(128.59.16.4)
to: disco.cs.columbia.edu(128.59.16.7)/32768
with error rate

random packet loss : 7(1/100 per packet)

bit error : 5(1/100000 per bit)

out of order : 9(1/100 per packet)

type,

newudpl -idynamo.cs.columbia.edu/* -odisco.cs.columbia.edu:0x8000 -v -L7 -B5 -O9

To stop the emulator,

press ctr-c
type any 'q' 'quit' 'stop' 'exit' from the console.

HISTORY

ChangeLog.html

AUTHUR

Akira Tsukamoto
at541@columbia.edu

ACKNOWLEDGEMENTS

For genarating a random variable corresponding to binomial distribution , I used the bnldev() function from
William H. Press, Brian P. Flannery, Saul A. Teukolsky, William T. Vetterling, 'Numerical Recipes in C' The Press Syndicate of the University of Cambridge, 1992.

This emulator was developed under supervising by,
Wenyu Jiang http://www.cs.columbia.edu/~wenyu/
Henning Schulzrinne http://www.cs.columbia.edu/~hgs/

I referred many codes in rtptools to understand the multitimer function.
http://www.cs.columbia.edu/IRT/software/rtptools/

Tetsu Iwama, He is good at math and taught me the rejection method.
Manager, Credit Risk Trading, Derivative Products Division, The Fuji Bank Limited, Mizuho Financial Group

Kuniyoshi Murata, He corrected my many English mistakes.
English-Japanese Interpreter mailto:kuni@ej-interpreter.net
Macintosh Webcast Specialist http://www.macwebcaster.com

COPYRIGHT

Copyright (C) 2001 by Columbia University; all rights reserved

Permission to use, copy, modify, and distribute this software and its documentation for not-for-profit research and educational purposes and without fee is hereby granted, provided that the above copyright notice appear in all copies and that both that the copyright notice and warranty disclaimer appear in supporting documentation, and that the names of the copyright holders or any of their entities not be used in advertising or publicity pertaining to distribution of the software without specific, written prior permission. Use of this software in whole or in parts for commercial advantage and by for-profit organizations requires a license.

The copyright holders disclaim all warranties with regard to this software, including all implied warranties of merchantability and fitness. In no event shall the copyright holders be liable for any special, indirect or consequential damages or any damages whatsoever resulting from loss of use, data or profits, whether in an action of contract, negligence or other tortuous action, arising out of or in connection with the use or performance of this software.

Last updated: 2001-12-12 by Akira Tsukamoto

random packet loss	:	7(1/100 per packet)
bit error	:	5(1/100000 per bit)
out of order	:	9(1/100 per packet)