PKTLG - An Ethernet Packet Load Generator
-----------------------------------------
PKTLG is a simple packet load generator, which can be used to produce
controlled amounts of ethernet background traffic. This is useful in
the testing of ethernet communications under various load conditions.

PKTLG interfaces to the ethernet card via a standard DOS packet driver,
this driver must be supplied by your ethernet card manufacturer, and is
included with most cards. See your network card documentation and software.

Packet drivers for a large assortment of ethernet cards are also available
from:
    Crynwr Software    11 Grant St.    Potsdam, NY 13676
This collection is available on SIMTEL and other software archive sites
under the filenames: PKTD*.ZIP (or whatever archive format is used)

You can also try the originators of the packet driver specification:
    FTP Software, Inc.   26 Princess St.   Wakefield, MA  01880-3004
    (617) 246-0900
for more information.


RUNNING PKTLG
-------------
Install the packet driver for your network card in accordance with the
card documentation. If possible, use the standard packet driver software
interrupt of 60 hex (0x60)... If you use a different interrupt, you will
have to specify the interrupt to PKTLG via a command line switch every
time you start it.

PKTLG must be run on multiple PC's. Each PC running PKTLG will broadcast
a wakeup packet at regular intervals, which is used to inform each PKTLG
of the presense of the other PKTLGs. As new PKTLGs are discovered, PKTLG
will begin transmitting a data stream to each one at the configured packet
rate. By controlling the PKTLG<->PKTLG packet rate, the size of the packets,
and the number of active PKTLGs on the network, you can control the network
traffic quite precisely.

Start PKTLG running on each PC by typing PKTLG at the DOS command prompt.
The following command line options are available:

  B=n       - Set broadcast packet length
    Specifies the length of the "wakeup" packets PKTLG transmits at
    regular intervals. Value must be from 1-500 data bytes.

  D=n       - Set data packet length
    Specifies the length of the data packets PKTLG transmits to each of
    the other PKTLG nodes. Value must be from 1-500 data bytes.

  F=xx/R/Sn - Selects how packets sent by PKTLG are filed with data.
        xx  - Two hex digits, fill packets with this byte value
        R   - Fill packets with randomly generated data
        Sn  - Fill with random, but begin with this seed value (0-65535)
              A given seed value will always generate the same random
              packet data.

  I=n       - Set broadcast packet interval
    Specifies the interval (seconds) that PKTLG wait between sending
    "wakeup" packets.

  P=xx      - Specify packet driver interrupt
    This option allows you to specify the software interrupt on which the
    packet driver has been installed. If not specified, PKTLG assumes the
    value of 60 hex (0x60) which is the standard packet driver interrupt.
 
  R=n       - Set data packet rate
    This value indicates the number of packets per second that you want
    PKTLG to try and send to EACH of the other PKTLG nodes on the network.
    If the number of packets/second times the number of active PKTLG nodes
    exceeds the capacity of your network interface, PKTLG will display the
    string "OVRN" in the top right hand corner of the screen to indicate
    that the network driver is unable to accept all of the packets.

  S=n       - Set screen update rate
    This setting determines how frequently PKTLG updates the on-screen
    displays. A lower number provides faster screen updates, but may
    interfere with packet transmission on slower PC's at high data
    rates.

  T=xxxx    - Set packet type
    Specifies the packet type which is used by PKTLG packets. This
    should be chosen to not conflict with other packet types in use
    on your network.

USING PKTLG
-----------
Once PKTLG begins running, operation is automatic. Each copy of PKTLG
running on the network will automatically "find" the other PKTLG's and
begin transferring traffic to them.

The rate configuration parameters (Data rate, Data packet size, Broadcast
interval and Broadcast size) can be fine-tuned while PKTLG is running,
by using the UP/DOWN arrows to select the item to configure, and the Right/
Left arrows (+/-1) or PgUp/PgDn keys (+/-10) to modify the item value.

To terminate PKTLG, press the ESC key.


Dunfield Development Services (DDS) offers software and firmware
development services specializing in systems and embedded applications.
For more information, visit: http://www.dunfield.com
